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.venv2/Lib/site-packages/alembic/__init__.py

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+from . import context
+from . import op
+
+__version__ = "1.13.1"

.venv2/Lib/site-packages/alembic/__main__.py

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+from .config import main
+
+if __name__ == "__main__":
+    main(prog="alembic")

.venv2/Lib/site-packages/alembic/autogenerate/__init__.py

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+from .api import _render_migration_diffs as _render_migration_diffs
+from .api import compare_metadata as compare_metadata
+from .api import produce_migrations as produce_migrations
+from .api import render_python_code as render_python_code
+from .api import RevisionContext as RevisionContext
+from .compare import _produce_net_changes as _produce_net_changes
+from .compare import comparators as comparators
+from .render import render_op_text as render_op_text
+from .render import renderers as renderers
+from .rewriter import Rewriter as Rewriter

.venv2/Lib/site-packages/alembic/autogenerate/api.py

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+from __future__ import annotations
+
+import contextlib
+from typing import Any
+from typing import Dict
+from typing import Iterator
+from typing import List
+from typing import Optional
+from typing import Sequence
+from typing import Set
+from typing import TYPE_CHECKING
+from typing import Union
+
+from sqlalchemy import inspect
+
+from . import compare
+from . import render
+from .. import util
+from ..operations import ops
+from ..util import sqla_compat
+
+"""Provide the 'autogenerate' feature which can produce migration operations
+automatically."""
+
+if TYPE_CHECKING:
+    from sqlalchemy.engine import Connection
+    from sqlalchemy.engine import Dialect
+    from sqlalchemy.engine import Inspector
+    from sqlalchemy.sql.schema import MetaData
+    from sqlalchemy.sql.schema import SchemaItem
+    from sqlalchemy.sql.schema import Table
+
+    from ..config import Config
+    from ..operations.ops import DowngradeOps
+    from ..operations.ops import MigrationScript
+    from ..operations.ops import UpgradeOps
+    from ..runtime.environment import NameFilterParentNames
+    from ..runtime.environment import NameFilterType
+    from ..runtime.environment import ProcessRevisionDirectiveFn
+    from ..runtime.environment import RenderItemFn
+    from ..runtime.migration import MigrationContext
+    from ..script.base import Script
+    from ..script.base import ScriptDirectory
+    from ..script.revision import _GetRevArg
+
+
+def compare_metadata(context: MigrationContext, metadata: MetaData) -> Any:
+    """Compare a database schema to that given in a
+    :class:`~sqlalchemy.schema.MetaData` instance.
+
+    The database connection is presented in the context
+    of a :class:`.MigrationContext` object, which
+    provides database connectivity as well as optional
+    comparison functions to use for datatypes and
+    server defaults - see the "autogenerate" arguments
+    at :meth:`.EnvironmentContext.configure`
+    for details on these.
+
+    The return format is a list of "diff" directives,
+    each representing individual differences::
+
+        from alembic.migration import MigrationContext
+        from alembic.autogenerate import compare_metadata
+        from sqlalchemy import (
+            create_engine,
+            MetaData,
+            Column,
+            Integer,
+            String,
+            Table,
+            text,
+        )
+        import pprint
+
+        engine = create_engine("sqlite://")
+
+        with engine.begin() as conn:
+            conn.execute(
+                text(
+                    '''
+                        create table foo (
+                            id integer not null primary key,
+                            old_data varchar,
+                            x integer
+                        )
+                    '''
+                )
+            )
+            conn.execute(text("create table bar (data varchar)"))
+
+        metadata = MetaData()
+        Table(
+            "foo",
+            metadata,
+            Column("id", Integer, primary_key=True),
+            Column("data", Integer),
+            Column("x", Integer, nullable=False),
+        )
+        Table("bat", metadata, Column("info", String))
+
+        mc = MigrationContext.configure(engine.connect())
+
+        diff = compare_metadata(mc, metadata)
+        pprint.pprint(diff, indent=2, width=20)
+
+    Output::
+
+        [
+            (
+                "add_table",
+                Table(
+                    "bat",
+                    MetaData(),
+                    Column("info", String(), table=<bat>),
+                    schema=None,
+                ),
+            ),
+            (
+                "remove_table",
+                Table(
+                    "bar",
+                    MetaData(),
+                    Column("data", VARCHAR(), table=<bar>),
+                    schema=None,
+                ),
+            ),
+            (
+                "add_column",
+                None,
+                "foo",
+                Column("data", Integer(), table=<foo>),
+            ),
+            [
+                (
+                    "modify_nullable",
+                    None,
+                    "foo",
+                    "x",
+                    {
+                        "existing_comment": None,
+                        "existing_server_default": False,
+                        "existing_type": INTEGER(),
+                    },
+                    True,
+                    False,
+                )
+            ],
+            (
+                "remove_column",
+                None,
+                "foo",
+                Column("old_data", VARCHAR(), table=<foo>),
+            ),
+        ]
+
+    :param context: a :class:`.MigrationContext`
+     instance.
+    :param metadata: a :class:`~sqlalchemy.schema.MetaData`
+     instance.
+
+    .. seealso::
+
+        :func:`.produce_migrations` - produces a :class:`.MigrationScript`
+        structure based on metadata comparison.
+
+    """
+
+    migration_script = produce_migrations(context, metadata)
+    assert migration_script.upgrade_ops is not None
+    return migration_script.upgrade_ops.as_diffs()
+
+
+def produce_migrations(
+    context: MigrationContext, metadata: MetaData
+) -> MigrationScript:
+    """Produce a :class:`.MigrationScript` structure based on schema
+    comparison.
+
+    This function does essentially what :func:`.compare_metadata` does,
+    but then runs the resulting list of diffs to produce the full
+    :class:`.MigrationScript` object.   For an example of what this looks like,
+    see the example in :ref:`customizing_revision`.
+
+    .. seealso::
+
+        :func:`.compare_metadata` - returns more fundamental "diff"
+        data from comparing a schema.
+
+    """
+
+    autogen_context = AutogenContext(context, metadata=metadata)
+
+    migration_script = ops.MigrationScript(
+        rev_id=None,
+        upgrade_ops=ops.UpgradeOps([]),
+        downgrade_ops=ops.DowngradeOps([]),
+    )
+
+    compare._populate_migration_script(autogen_context, migration_script)
+
+    return migration_script
+
+
+def render_python_code(
+    up_or_down_op: Union[UpgradeOps, DowngradeOps],
+    sqlalchemy_module_prefix: str = "sa.",
+    alembic_module_prefix: str = "op.",
+    render_as_batch: bool = False,
+    imports: Sequence[str] = (),
+    render_item: Optional[RenderItemFn] = None,
+    migration_context: Optional[MigrationContext] = None,
+    user_module_prefix: Optional[str] = None,
+) -> str:
+    """Render Python code given an :class:`.UpgradeOps` or
+    :class:`.DowngradeOps` object.
+
+    This is a convenience function that can be used to test the
+    autogenerate output of a user-defined :class:`.MigrationScript` structure.
+
+    :param up_or_down_op: :class:`.UpgradeOps` or :class:`.DowngradeOps` object
+    :param sqlalchemy_module_prefix: module prefix for SQLAlchemy objects
+    :param alembic_module_prefix: module prefix for Alembic constructs
+    :param render_as_batch: use "batch operations" style for rendering
+    :param imports: sequence of import symbols to add
+    :param render_item: callable to render items
+    :param migration_context: optional :class:`.MigrationContext`
+    :param user_module_prefix: optional string prefix for user-defined types
+
+     .. versionadded:: 1.11.0
+
+    """
+    opts = {
+        "sqlalchemy_module_prefix": sqlalchemy_module_prefix,
+        "alembic_module_prefix": alembic_module_prefix,
+        "render_item": render_item,
+        "render_as_batch": render_as_batch,
+        "user_module_prefix": user_module_prefix,
+    }
+
+    if migration_context is None:
+        from ..runtime.migration import MigrationContext
+        from sqlalchemy.engine.default import DefaultDialect
+
+        migration_context = MigrationContext.configure(
+            dialect=DefaultDialect()
+        )
+
+    autogen_context = AutogenContext(migration_context, opts=opts)
+    autogen_context.imports = set(imports)
+    return render._indent(
+        render._render_cmd_body(up_or_down_op, autogen_context)
+    )
+
+
+def _render_migration_diffs(
+    context: MigrationContext, template_args: Dict[Any, Any]
+) -> None:
+    """legacy, used by test_autogen_composition at the moment"""
+
+    autogen_context = AutogenContext(context)
+
+    upgrade_ops = ops.UpgradeOps([])
+    compare._produce_net_changes(autogen_context, upgrade_ops)
+
+    migration_script = ops.MigrationScript(
+        rev_id=None,
+        upgrade_ops=upgrade_ops,
+        downgrade_ops=upgrade_ops.reverse(),
+    )
+
+    render._render_python_into_templatevars(
+        autogen_context, migration_script, template_args
+    )
+
+
+class AutogenContext:
+    """Maintains configuration and state that's specific to an
+    autogenerate operation."""
+
+    metadata: Optional[MetaData] = None
+    """The :class:`~sqlalchemy.schema.MetaData` object
+    representing the destination.
+
+    This object is the one that is passed within ``env.py``
+    to the :paramref:`.EnvironmentContext.configure.target_metadata`
+    parameter.  It represents the structure of :class:`.Table` and other
+    objects as stated in the current database model, and represents the
+    destination structure for the database being examined.
+
+    While the :class:`~sqlalchemy.schema.MetaData` object is primarily
+    known as a collection of :class:`~sqlalchemy.schema.Table` objects,
+    it also has an :attr:`~sqlalchemy.schema.MetaData.info` dictionary
+    that may be used by end-user schemes to store additional schema-level
+    objects that are to be compared in custom autogeneration schemes.
+
+    """
+
+    connection: Optional[Connection] = None
+    """The :class:`~sqlalchemy.engine.base.Connection` object currently
+    connected to the database backend being compared.
+
+    This is obtained from the :attr:`.MigrationContext.bind` and is
+    ultimately set up in the ``env.py`` script.
+
+    """
+
+    dialect: Optional[Dialect] = None
+    """The :class:`~sqlalchemy.engine.Dialect` object currently in use.
+
+    This is normally obtained from the
+    :attr:`~sqlalchemy.engine.base.Connection.dialect` attribute.
+
+    """
+
+    imports: Set[str] = None  # type: ignore[assignment]
+    """A ``set()`` which contains string Python import directives.
+
+    The directives are to be rendered into the ``${imports}`` section
+    of a script template.  The set is normally empty and can be modified
+    within hooks such as the
+    :paramref:`.EnvironmentContext.configure.render_item` hook.
+
+    .. seealso::
+
+        :ref:`autogen_render_types`
+
+    """
+
+    migration_context: MigrationContext = None  # type: ignore[assignment]
+    """The :class:`.MigrationContext` established by the ``env.py`` script."""
+
+    def __init__(
+        self,
+        migration_context: MigrationContext,
+        metadata: Optional[MetaData] = None,
+        opts: Optional[Dict[str, Any]] = None,
+        autogenerate: bool = True,
+    ) -> None:
+        if (
+            autogenerate
+            and migration_context is not None
+            and migration_context.as_sql
+        ):
+            raise util.CommandError(
+                "autogenerate can't use as_sql=True as it prevents querying "
+                "the database for schema information"
+            )
+
+        if opts is None:
+            opts = migration_context.opts
+
+        self.metadata = metadata = (
+            opts.get("target_metadata", None) if metadata is None else metadata
+        )
+
+        if (
+            autogenerate
+            and metadata is None
+            and migration_context is not None
+            and migration_context.script is not None
+        ):
+            raise util.CommandError(
+                "Can't proceed with --autogenerate option; environment "
+                "script %s does not provide "
+                "a MetaData object or sequence of objects to the context."
+                % (migration_context.script.env_py_location)
+            )
+
+        include_object = opts.get("include_object", None)
+        include_name = opts.get("include_name", None)
+
+        object_filters = []
+        name_filters = []
+        if include_object:
+            object_filters.append(include_object)
+        if include_name:
+            name_filters.append(include_name)
+
+        self._object_filters = object_filters
+        self._name_filters = name_filters
+
+        self.migration_context = migration_context
+        if self.migration_context is not None:
+            self.connection = self.migration_context.bind
+            self.dialect = self.migration_context.dialect
+
+        self.imports = set()
+        self.opts: Dict[str, Any] = opts
+        self._has_batch: bool = False
+
+    @util.memoized_property
+    def inspector(self) -> Inspector:
+        if self.connection is None:
+            raise TypeError(
+                "can't return inspector as this "
+                "AutogenContext has no database connection"
+            )
+        return inspect(self.connection)
+
+    @contextlib.contextmanager
+    def _within_batch(self) -> Iterator[None]:
+        self._has_batch = True
+        yield
+        self._has_batch = False
+
+    def run_name_filters(
+        self,
+        name: Optional[str],
+        type_: NameFilterType,
+        parent_names: NameFilterParentNames,
+    ) -> bool:
+        """Run the context's name filters and return True if the targets
+        should be part of the autogenerate operation.
+
+        This method should be run for every kind of name encountered within the
+        reflection side of an autogenerate operation, giving the environment
+        the chance to filter what names should be reflected as database
+        objects.  The filters here are produced directly via the
+        :paramref:`.EnvironmentContext.configure.include_name` parameter.
+
+        """
+        if "schema_name" in parent_names:
+            if type_ == "table":
+                table_name = name
+            else:
+                table_name = parent_names.get("table_name", None)
+            if table_name:
+                schema_name = parent_names["schema_name"]
+                if schema_name:
+                    parent_names["schema_qualified_table_name"] = "%s.%s" % (
+                        schema_name,
+                        table_name,
+                    )
+                else:
+                    parent_names["schema_qualified_table_name"] = table_name
+
+        for fn in self._name_filters:
+            if not fn(name, type_, parent_names):
+                return False
+        else:
+            return True
+
+    def run_object_filters(
+        self,
+        object_: SchemaItem,
+        name: sqla_compat._ConstraintName,
+        type_: NameFilterType,
+        reflected: bool,
+        compare_to: Optional[SchemaItem],
+    ) -> bool:
+        """Run the context's object filters and return True if the targets
+        should be part of the autogenerate operation.
+
+        This method should be run for every kind of object encountered within
+        an autogenerate operation, giving the environment the chance
+        to filter what objects should be included in the comparison.
+        The filters here are produced directly via the
+        :paramref:`.EnvironmentContext.configure.include_object` parameter.
+
+        """
+        for fn in self._object_filters:
+            if not fn(object_, name, type_, reflected, compare_to):
+                return False
+        else:
+            return True
+
+    run_filters = run_object_filters
+
+    @util.memoized_property
+    def sorted_tables(self) -> List[Table]:
+        """Return an aggregate of the :attr:`.MetaData.sorted_tables`
+        collection(s).
+
+        For a sequence of :class:`.MetaData` objects, this
+        concatenates the :attr:`.MetaData.sorted_tables` collection
+        for each individual :class:`.MetaData`  in the order of the
+        sequence.  It does **not** collate the sorted tables collections.
+
+        """
+        result = []
+        for m in util.to_list(self.metadata):
+            result.extend(m.sorted_tables)
+        return result
+
+    @util.memoized_property
+    def table_key_to_table(self) -> Dict[str, Table]:
+        """Return an aggregate  of the :attr:`.MetaData.tables` dictionaries.
+
+        The :attr:`.MetaData.tables` collection is a dictionary of table key
+        to :class:`.Table`; this method aggregates the dictionary across
+        multiple :class:`.MetaData` objects into one dictionary.
+
+        Duplicate table keys are **not** supported; if two :class:`.MetaData`
+        objects contain the same table key, an exception is raised.
+
+        """
+        result: Dict[str, Table] = {}
+        for m in util.to_list(self.metadata):
+            intersect = set(result).intersection(set(m.tables))
+            if intersect:
+                raise ValueError(
+                    "Duplicate table keys across multiple "
+                    "MetaData objects: %s"
+                    % (", ".join('"%s"' % key for key in sorted(intersect)))
+                )
+
+            result.update(m.tables)
+        return result
+
+
+class RevisionContext:
+    """Maintains configuration and state that's specific to a revision
+    file generation operation."""
+
+    generated_revisions: List[MigrationScript]
+    process_revision_directives: Optional[ProcessRevisionDirectiveFn]
+
+    def __init__(
+        self,
+        config: Config,
+        script_directory: ScriptDirectory,
+        command_args: Dict[str, Any],
+        process_revision_directives: Optional[
+            ProcessRevisionDirectiveFn
+        ] = None,
+    ) -> None:
+        self.config = config
+        self.script_directory = script_directory
+        self.command_args = command_args
+        self.process_revision_directives = process_revision_directives
+        self.template_args = {
+            "config": config  # Let templates use config for
+            # e.g. multiple databases
+        }
+        self.generated_revisions = [self._default_revision()]
+
+    def _to_script(
+        self, migration_script: MigrationScript
+    ) -> Optional[Script]:
+        template_args: Dict[str, Any] = self.template_args.copy()
+
+        if getattr(migration_script, "_needs_render", False):
+            autogen_context = self._last_autogen_context
+
+            # clear out existing imports if we are doing multiple
+            # renders
+            autogen_context.imports = set()
+            if migration_script.imports:
+                autogen_context.imports.update(migration_script.imports)
+            render._render_python_into_templatevars(
+                autogen_context, migration_script, template_args
+            )
+
+        assert migration_script.rev_id is not None
+        return self.script_directory.generate_revision(
+            migration_script.rev_id,
+            migration_script.message,
+            refresh=True,
+            head=migration_script.head,
+            splice=migration_script.splice,
+            branch_labels=migration_script.branch_label,
+            version_path=migration_script.version_path,
+            depends_on=migration_script.depends_on,
+            **template_args,
+        )
+
+    def run_autogenerate(
+        self, rev: _GetRevArg, migration_context: MigrationContext
+    ) -> None:
+        self._run_environment(rev, migration_context, True)
+
+    def run_no_autogenerate(
+        self, rev: _GetRevArg, migration_context: MigrationContext
+    ) -> None:
+        self._run_environment(rev, migration_context, False)
+
+    def _run_environment(
+        self,
+        rev: _GetRevArg,
+        migration_context: MigrationContext,
+        autogenerate: bool,
+    ) -> None:
+        if autogenerate:
+            if self.command_args["sql"]:
+                raise util.CommandError(
+                    "Using --sql with --autogenerate does not make any sense"
+                )
+            if set(self.script_directory.get_revisions(rev)) != set(
+                self.script_directory.get_revisions("heads")
+            ):
+                raise util.CommandError("Target database is not up to date.")
+
+        upgrade_token = migration_context.opts["upgrade_token"]
+        downgrade_token = migration_context.opts["downgrade_token"]
+
+        migration_script = self.generated_revisions[-1]
+        if not getattr(migration_script, "_needs_render", False):
+            migration_script.upgrade_ops_list[-1].upgrade_token = upgrade_token
+            migration_script.downgrade_ops_list[
+                -1
+            ].downgrade_token = downgrade_token
+            migration_script._needs_render = True
+        else:
+            migration_script._upgrade_ops.append(
+                ops.UpgradeOps([], upgrade_token=upgrade_token)
+            )
+            migration_script._downgrade_ops.append(
+                ops.DowngradeOps([], downgrade_token=downgrade_token)
+            )
+
+        autogen_context = AutogenContext(
+            migration_context, autogenerate=autogenerate
+        )
+        self._last_autogen_context: AutogenContext = autogen_context
+
+        if autogenerate:
+            compare._populate_migration_script(
+                autogen_context, migration_script
+            )
+
+        if self.process_revision_directives:
+            self.process_revision_directives(
+                migration_context, rev, self.generated_revisions
+            )
+
+        hook = migration_context.opts["process_revision_directives"]
+        if hook:
+            hook(migration_context, rev, self.generated_revisions)
+
+        for migration_script in self.generated_revisions:
+            migration_script._needs_render = True
+
+    def _default_revision(self) -> MigrationScript:
+        command_args: Dict[str, Any] = self.command_args
+        op = ops.MigrationScript(
+            rev_id=command_args["rev_id"] or util.rev_id(),
+            message=command_args["message"],
+            upgrade_ops=ops.UpgradeOps([]),
+            downgrade_ops=ops.DowngradeOps([]),
+            head=command_args["head"],
+            splice=command_args["splice"],
+            branch_label=command_args["branch_label"],
+            version_path=command_args["version_path"],
+            depends_on=command_args["depends_on"],
+        )
+        return op
+
+    def generate_scripts(self) -> Iterator[Optional[Script]]:
+        for generated_revision in self.generated_revisions:
+            yield self._to_script(generated_revision)

.venv2/Lib/site-packages/alembic/autogenerate/rewriter.py

@@ -0,0 +1,240 @@
+from __future__ import annotations
+
+from typing import Any
+from typing import Callable
+from typing import Iterator
+from typing import List
+from typing import Tuple
+from typing import Type
+from typing import TYPE_CHECKING
+from typing import Union
+
+from .. import util
+from ..operations import ops
+
+if TYPE_CHECKING:
+    from ..operations.ops import AddColumnOp
+    from ..operations.ops import AlterColumnOp
+    from ..operations.ops import CreateTableOp
+    from ..operations.ops import DowngradeOps
+    from ..operations.ops import MigrateOperation
+    from ..operations.ops import MigrationScript
+    from ..operations.ops import ModifyTableOps
+    from ..operations.ops import OpContainer
+    from ..operations.ops import UpgradeOps
+    from ..runtime.migration import MigrationContext
+    from ..script.revision import _GetRevArg
+
+ProcessRevisionDirectiveFn = Callable[
+    ["MigrationContext", "_GetRevArg", List["MigrationScript"]], None
+]
+
+
+class Rewriter:
+    """A helper object that allows easy 'rewriting' of ops streams.
+
+    The :class:`.Rewriter` object is intended to be passed along
+    to the
+    :paramref:`.EnvironmentContext.configure.process_revision_directives`
+    parameter in an ``env.py`` script.    Once constructed, any number
+    of "rewrites" functions can be associated with it, which will be given
+    the opportunity to modify the structure without having to have explicit
+    knowledge of the overall structure.
+
+    The function is passed the :class:`.MigrationContext` object and
+    ``revision`` tuple that are passed to the  :paramref:`.Environment
+    Context.configure.process_revision_directives` function normally,
+    and the third argument is an individual directive of the type
+    noted in the decorator.  The function has the choice of  returning
+    a single op directive, which normally can be the directive that
+    was actually passed, or a new directive to replace it, or a list
+    of zero or more directives to replace it.
+
+    .. seealso::
+
+        :ref:`autogen_rewriter` - usage example
+
+    """
+
+    _traverse = util.Dispatcher()
+
+    _chained: Tuple[Union[ProcessRevisionDirectiveFn, Rewriter], ...] = ()
+
+    def __init__(self) -> None:
+        self.dispatch = util.Dispatcher()
+
+    def chain(
+        self,
+        other: Union[
+            ProcessRevisionDirectiveFn,
+            Rewriter,
+        ],
+    ) -> Rewriter:
+        """Produce a "chain" of this :class:`.Rewriter` to another.
+
+        This allows two or more rewriters to operate serially on a stream,
+        e.g.::
+
+            writer1 = autogenerate.Rewriter()
+            writer2 = autogenerate.Rewriter()
+
+
+            @writer1.rewrites(ops.AddColumnOp)
+            def add_column_nullable(context, revision, op):
+                op.column.nullable = True
+                return op
+
+
+            @writer2.rewrites(ops.AddColumnOp)
+            def add_column_idx(context, revision, op):
+                idx_op = ops.CreateIndexOp(
+                    "ixc", op.table_name, [op.column.name]
+                )
+                return [op, idx_op]
+
+            writer = writer1.chain(writer2)
+
+        :param other: a :class:`.Rewriter` instance
+        :return: a new :class:`.Rewriter` that will run the operations
+         of this writer, then the "other" writer, in succession.
+
+        """
+        wr = self.__class__.__new__(self.__class__)
+        wr.__dict__.update(self.__dict__)
+        wr._chained += (other,)
+        return wr
+
+    def rewrites(
+        self,
+        operator: Union[
+            Type[AddColumnOp],
+            Type[MigrateOperation],
+            Type[AlterColumnOp],
+            Type[CreateTableOp],
+            Type[ModifyTableOps],
+        ],
+    ) -> Callable[..., Any]:
+        """Register a function as rewriter for a given type.
+
+        The function should receive three arguments, which are
+        the :class:`.MigrationContext`, a ``revision`` tuple, and
+        an op directive of the type indicated.  E.g.::
+
+            @writer1.rewrites(ops.AddColumnOp)
+            def add_column_nullable(context, revision, op):
+                op.column.nullable = True
+                return op
+
+        """
+        return self.dispatch.dispatch_for(operator)
+
+    def _rewrite(
+        self,
+        context: MigrationContext,
+        revision: _GetRevArg,
+        directive: MigrateOperation,
+    ) -> Iterator[MigrateOperation]:
+        try:
+            _rewriter = self.dispatch.dispatch(directive)
+        except ValueError:
+            _rewriter = None
+            yield directive
+        else:
+            if self in directive._mutations:
+                yield directive
+            else:
+                for r_directive in util.to_list(
+                    _rewriter(context, revision, directive), []
+                ):
+                    r_directive._mutations = r_directive._mutations.union(
+                        [self]
+                    )
+                    yield r_directive
+
+    def __call__(
+        self,
+        context: MigrationContext,
+        revision: _GetRevArg,
+        directives: List[MigrationScript],
+    ) -> None:
+        self.process_revision_directives(context, revision, directives)
+        for process_revision_directives in self._chained:
+            process_revision_directives(context, revision, directives)
+
+    @_traverse.dispatch_for(ops.MigrationScript)
+    def _traverse_script(
+        self,
+        context: MigrationContext,
+        revision: _GetRevArg,
+        directive: MigrationScript,
+    ) -> None:
+        upgrade_ops_list: List[UpgradeOps] = []
+        for upgrade_ops in directive.upgrade_ops_list:
+            ret = self._traverse_for(context, revision, upgrade_ops)
+            if len(ret) != 1:
+                raise ValueError(
+                    "Can only return single object for UpgradeOps traverse"
+                )
+            upgrade_ops_list.append(ret[0])
+
+        directive.upgrade_ops = upgrade_ops_list  # type: ignore
+
+        downgrade_ops_list: List[DowngradeOps] = []
+        for downgrade_ops in directive.downgrade_ops_list:
+            ret = self._traverse_for(context, revision, downgrade_ops)
+            if len(ret) != 1:
+                raise ValueError(
+                    "Can only return single object for DowngradeOps traverse"
+                )
+            downgrade_ops_list.append(ret[0])
+        directive.downgrade_ops = downgrade_ops_list  # type: ignore
+
+    @_traverse.dispatch_for(ops.OpContainer)
+    def _traverse_op_container(
+        self,
+        context: MigrationContext,
+        revision: _GetRevArg,
+        directive: OpContainer,
+    ) -> None:
+        self._traverse_list(context, revision, directive.ops)
+
+    @_traverse.dispatch_for(ops.MigrateOperation)
+    def _traverse_any_directive(
+        self,
+        context: MigrationContext,
+        revision: _GetRevArg,
+        directive: MigrateOperation,
+    ) -> None:
+        pass
+
+    def _traverse_for(
+        self,
+        context: MigrationContext,
+        revision: _GetRevArg,
+        directive: MigrateOperation,
+    ) -> Any:
+        directives = list(self._rewrite(context, revision, directive))
+        for directive in directives:
+            traverser = self._traverse.dispatch(directive)
+            traverser(self, context, revision, directive)
+        return directives
+
+    def _traverse_list(
+        self,
+        context: MigrationContext,
+        revision: _GetRevArg,
+        directives: Any,
+    ) -> None:
+        dest = []
+        for directive in directives:
+            dest.extend(self._traverse_for(context, revision, directive))
+
+        directives[:] = dest
+
+    def process_revision_directives(
+        self,
+        context: MigrationContext,
+        revision: _GetRevArg,
+        directives: List[MigrationScript],
+    ) -> None:
+        self._traverse_list(context, revision, directives)

.venv2/Lib/site-packages/alembic/command.py

@@ -0,0 +1,749 @@
+# mypy: allow-untyped-defs, allow-untyped-calls
+
+from __future__ import annotations
+
+import os
+from typing import List
+from typing import Optional
+from typing import TYPE_CHECKING
+from typing import Union
+
+from . import autogenerate as autogen
+from . import util
+from .runtime.environment import EnvironmentContext
+from .script import ScriptDirectory
+
+if TYPE_CHECKING:
+    from alembic.config import Config
+    from alembic.script.base import Script
+    from alembic.script.revision import _RevIdType
+    from .runtime.environment import ProcessRevisionDirectiveFn
+
+
+def list_templates(config: Config) -> None:
+    """List available templates.
+
+    :param config: a :class:`.Config` object.
+
+    """
+
+    config.print_stdout("Available templates:\n")
+    for tempname in os.listdir(config.get_template_directory()):
+        with open(
+            os.path.join(config.get_template_directory(), tempname, "README")
+        ) as readme:
+            synopsis = next(readme).rstrip()
+        config.print_stdout("%s - %s", tempname, synopsis)
+
+    config.print_stdout("\nTemplates are used via the 'init' command, e.g.:")
+    config.print_stdout("\n  alembic init --template generic ./scripts")
+
+
+def init(
+    config: Config,
+    directory: str,
+    template: str = "generic",
+    package: bool = False,
+) -> None:
+    """Initialize a new scripts directory.
+
+    :param config: a :class:`.Config` object.
+
+    :param directory: string path of the target directory
+
+    :param template: string name of the migration environment template to
+     use.
+
+    :param package: when True, write ``__init__.py`` files into the
+     environment location as well as the versions/ location.
+
+    """
+
+    if os.access(directory, os.F_OK) and os.listdir(directory):
+        raise util.CommandError(
+            "Directory %s already exists and is not empty" % directory
+        )
+
+    template_dir = os.path.join(config.get_template_directory(), template)
+    if not os.access(template_dir, os.F_OK):
+        raise util.CommandError("No such template %r" % template)
+
+    if not os.access(directory, os.F_OK):
+        with util.status(
+            f"Creating directory {os.path.abspath(directory)!r}",
+            **config.messaging_opts,
+        ):
+            os.makedirs(directory)
+
+    versions = os.path.join(directory, "versions")
+    with util.status(
+        f"Creating directory {os.path.abspath(versions)!r}",
+        **config.messaging_opts,
+    ):
+        os.makedirs(versions)
+
+    script = ScriptDirectory(directory)
+
+    config_file: str | None = None
+    for file_ in os.listdir(template_dir):
+        file_path = os.path.join(template_dir, file_)
+        if file_ == "alembic.ini.mako":
+            assert config.config_file_name is not None
+            config_file = os.path.abspath(config.config_file_name)
+            if os.access(config_file, os.F_OK):
+                util.msg(
+                    f"File {config_file!r} already exists, skipping",
+                    **config.messaging_opts,
+                )
+            else:
+                script._generate_template(
+                    file_path, config_file, script_location=directory
+                )
+        elif os.path.isfile(file_path):
+            output_file = os.path.join(directory, file_)
+            script._copy_file(file_path, output_file)
+
+    if package:
+        for path in [
+            os.path.join(os.path.abspath(directory), "__init__.py"),
+            os.path.join(os.path.abspath(versions), "__init__.py"),
+        ]:
+            with util.status(f"Adding {path!r}", **config.messaging_opts):
+                with open(path, "w"):
+                    pass
+
+    assert config_file is not None
+    util.msg(
+        "Please edit configuration/connection/logging "
+        f"settings in {config_file!r} before proceeding.",
+        **config.messaging_opts,
+    )
+
+
+def revision(
+    config: Config,
+    message: Optional[str] = None,
+    autogenerate: bool = False,
+    sql: bool = False,
+    head: str = "head",
+    splice: bool = False,
+    branch_label: Optional[_RevIdType] = None,
+    version_path: Optional[str] = None,
+    rev_id: Optional[str] = None,
+    depends_on: Optional[str] = None,
+    process_revision_directives: Optional[ProcessRevisionDirectiveFn] = None,
+) -> Union[Optional[Script], List[Optional[Script]]]:
+    """Create a new revision file.
+
+    :param config: a :class:`.Config` object.
+
+    :param message: string message to apply to the revision; this is the
+     ``-m`` option to ``alembic revision``.
+
+    :param autogenerate: whether or not to autogenerate the script from
+     the database; this is the ``--autogenerate`` option to
+     ``alembic revision``.
+
+    :param sql: whether to dump the script out as a SQL string; when specified,
+     the script is dumped to stdout.  This is the ``--sql`` option to
+     ``alembic revision``.
+
+    :param head: head revision to build the new revision upon as a parent;
+     this is the ``--head`` option to ``alembic revision``.
+
+    :param splice: whether or not the new revision should be made into a
+     new head of its own; is required when the given ``head`` is not itself
+     a head.  This is the ``--splice`` option to ``alembic revision``.
+
+    :param branch_label: string label to apply to the branch; this is the
+     ``--branch-label`` option to ``alembic revision``.
+
+    :param version_path: string symbol identifying a specific version path
+     from the configuration; this is the ``--version-path`` option to
+     ``alembic revision``.
+
+    :param rev_id: optional revision identifier to use instead of having
+     one generated; this is the ``--rev-id`` option to ``alembic revision``.
+
+    :param depends_on: optional list of "depends on" identifiers; this is the
+     ``--depends-on`` option to ``alembic revision``.
+
+    :param process_revision_directives: this is a callable that takes the
+     same form as the callable described at
+     :paramref:`.EnvironmentContext.configure.process_revision_directives`;
+     will be applied to the structure generated by the revision process
+     where it can be altered programmatically.   Note that unlike all
+     the other parameters, this option is only available via programmatic
+     use of :func:`.command.revision`
+
+    """
+
+    script_directory = ScriptDirectory.from_config(config)
+
+    command_args = dict(
+        message=message,
+        autogenerate=autogenerate,
+        sql=sql,
+        head=head,
+        splice=splice,
+        branch_label=branch_label,
+        version_path=version_path,
+        rev_id=rev_id,
+        depends_on=depends_on,
+    )
+    revision_context = autogen.RevisionContext(
+        config,
+        script_directory,
+        command_args,
+        process_revision_directives=process_revision_directives,
+    )
+
+    environment = util.asbool(config.get_main_option("revision_environment"))
+
+    if autogenerate:
+        environment = True
+
+        if sql:
+            raise util.CommandError(
+                "Using --sql with --autogenerate does not make any sense"
+            )
+
+        def retrieve_migrations(rev, context):
+            revision_context.run_autogenerate(rev, context)
+            return []
+
+    elif environment:
+
+        def retrieve_migrations(rev, context):
+            revision_context.run_no_autogenerate(rev, context)
+            return []
+
+    elif sql:
+        raise util.CommandError(
+            "Using --sql with the revision command when "
+            "revision_environment is not configured does not make any sense"
+        )
+
+    if environment:
+        with EnvironmentContext(
+            config,
+            script_directory,
+            fn=retrieve_migrations,
+            as_sql=sql,
+            template_args=revision_context.template_args,
+            revision_context=revision_context,
+        ):
+            script_directory.run_env()
+
+        # the revision_context now has MigrationScript structure(s) present.
+        # these could theoretically be further processed / rewritten *here*,
+        # in addition to the hooks present within each run_migrations() call,
+        # or at the end of env.py run_migrations_online().
+
+    scripts = [script for script in revision_context.generate_scripts()]
+    if len(scripts) == 1:
+        return scripts[0]
+    else:
+        return scripts
+
+
+def check(config: "Config") -> None:
+    """Check if revision command with autogenerate has pending upgrade ops.
+
+    :param config: a :class:`.Config` object.
+
+    .. versionadded:: 1.9.0
+
+    """
+
+    script_directory = ScriptDirectory.from_config(config)
+
+    command_args = dict(
+        message=None,
+        autogenerate=True,
+        sql=False,
+        head="head",
+        splice=False,
+        branch_label=None,
+        version_path=None,
+        rev_id=None,
+        depends_on=None,
+    )
+    revision_context = autogen.RevisionContext(
+        config,
+        script_directory,
+        command_args,
+    )
+
+    def retrieve_migrations(rev, context):
+        revision_context.run_autogenerate(rev, context)
+        return []
+
+    with EnvironmentContext(
+        config,
+        script_directory,
+        fn=retrieve_migrations,
+        as_sql=False,
+        template_args=revision_context.template_args,
+        revision_context=revision_context,
+    ):
+        script_directory.run_env()
+
+    # the revision_context now has MigrationScript structure(s) present.
+
+    migration_script = revision_context.generated_revisions[-1]
+    diffs = []
+    for upgrade_ops in migration_script.upgrade_ops_list:
+        diffs.extend(upgrade_ops.as_diffs())
+
+    if diffs:
+        raise util.AutogenerateDiffsDetected(
+            f"New upgrade operations detected: {diffs}"
+        )
+    else:
+        config.print_stdout("No new upgrade operations detected.")
+
+
+def merge(
+    config: Config,
+    revisions: _RevIdType,
+    message: Optional[str] = None,
+    branch_label: Optional[_RevIdType] = None,
+    rev_id: Optional[str] = None,
+) -> Optional[Script]:
+    """Merge two revisions together.  Creates a new migration file.
+
+    :param config: a :class:`.Config` instance
+
+    :param message: string message to apply to the revision
+
+    :param branch_label: string label name to apply to the new revision
+
+    :param rev_id: hardcoded revision identifier instead of generating a new
+     one.
+
+    .. seealso::
+
+        :ref:`branches`
+
+    """
+
+    script = ScriptDirectory.from_config(config)
+    template_args = {
+        "config": config  # Let templates use config for
+        # e.g. multiple databases
+    }
+
+    environment = util.asbool(config.get_main_option("revision_environment"))
+
+    if environment:
+
+        def nothing(rev, context):
+            return []
+
+        with EnvironmentContext(
+            config,
+            script,
+            fn=nothing,
+            as_sql=False,
+            template_args=template_args,
+        ):
+            script.run_env()
+
+    return script.generate_revision(
+        rev_id or util.rev_id(),
+        message,
+        refresh=True,
+        head=revisions,
+        branch_labels=branch_label,
+        **template_args,  # type:ignore[arg-type]
+    )
+
+
+def upgrade(
+    config: Config,
+    revision: str,
+    sql: bool = False,
+    tag: Optional[str] = None,
+) -> None:
+    """Upgrade to a later version.
+
+    :param config: a :class:`.Config` instance.
+
+    :param revision: string revision target or range for --sql mode
+
+    :param sql: if True, use ``--sql`` mode
+
+    :param tag: an arbitrary "tag" that can be intercepted by custom
+     ``env.py`` scripts via the :meth:`.EnvironmentContext.get_tag_argument`
+     method.
+
+    """
+
+    script = ScriptDirectory.from_config(config)
+
+    starting_rev = None
+    if ":" in revision:
+        if not sql:
+            raise util.CommandError("Range revision not allowed")
+        starting_rev, revision = revision.split(":", 2)
+
+    def upgrade(rev, context):
+        return script._upgrade_revs(revision, rev)
+
+    with EnvironmentContext(
+        config,
+        script,
+        fn=upgrade,
+        as_sql=sql,
+        starting_rev=starting_rev,
+        destination_rev=revision,
+        tag=tag,
+    ):
+        script.run_env()
+
+
+def downgrade(
+    config: Config,
+    revision: str,
+    sql: bool = False,
+    tag: Optional[str] = None,
+) -> None:
+    """Revert to a previous version.
+
+    :param config: a :class:`.Config` instance.
+
+    :param revision: string revision target or range for --sql mode
+
+    :param sql: if True, use ``--sql`` mode
+
+    :param tag: an arbitrary "tag" that can be intercepted by custom
+     ``env.py`` scripts via the :meth:`.EnvironmentContext.get_tag_argument`
+     method.
+
+    """
+
+    script = ScriptDirectory.from_config(config)
+    starting_rev = None
+    if ":" in revision:
+        if not sql:
+            raise util.CommandError("Range revision not allowed")
+        starting_rev, revision = revision.split(":", 2)
+    elif sql:
+        raise util.CommandError(
+            "downgrade with --sql requires <fromrev>:<torev>"
+        )
+
+    def downgrade(rev, context):
+        return script._downgrade_revs(revision, rev)
+
+    with EnvironmentContext(
+        config,
+        script,
+        fn=downgrade,
+        as_sql=sql,
+        starting_rev=starting_rev,
+        destination_rev=revision,
+        tag=tag,
+    ):
+        script.run_env()
+
+
+def show(config, rev):
+    """Show the revision(s) denoted by the given symbol.
+
+    :param config: a :class:`.Config` instance.
+
+    :param revision: string revision target
+
+    """
+
+    script = ScriptDirectory.from_config(config)
+
+    if rev == "current":
+
+        def show_current(rev, context):
+            for sc in script.get_revisions(rev):
+                config.print_stdout(sc.log_entry)
+            return []
+
+        with EnvironmentContext(config, script, fn=show_current):
+            script.run_env()
+    else:
+        for sc in script.get_revisions(rev):
+            config.print_stdout(sc.log_entry)
+
+
+def history(
+    config: Config,
+    rev_range: Optional[str] = None,
+    verbose: bool = False,
+    indicate_current: bool = False,
+) -> None:
+    """List changeset scripts in chronological order.
+
+    :param config: a :class:`.Config` instance.
+
+    :param rev_range: string revision range
+
+    :param verbose: output in verbose mode.
+
+    :param indicate_current: indicate current revision.
+
+    """
+    base: Optional[str]
+    head: Optional[str]
+    script = ScriptDirectory.from_config(config)
+    if rev_range is not None:
+        if ":" not in rev_range:
+            raise util.CommandError(
+                "History range requires [start]:[end], " "[start]:, or :[end]"
+            )
+        base, head = rev_range.strip().split(":")
+    else:
+        base = head = None
+
+    environment = (
+        util.asbool(config.get_main_option("revision_environment"))
+        or indicate_current
+    )
+
+    def _display_history(config, script, base, head, currents=()):
+        for sc in script.walk_revisions(
+            base=base or "base", head=head or "heads"
+        ):
+            if indicate_current:
+                sc._db_current_indicator = sc.revision in currents
+
+            config.print_stdout(
+                sc.cmd_format(
+                    verbose=verbose,
+                    include_branches=True,
+                    include_doc=True,
+                    include_parents=True,
+                )
+            )
+
+    def _display_history_w_current(config, script, base, head):
+        def _display_current_history(rev, context):
+            if head == "current":
+                _display_history(config, script, base, rev, rev)
+            elif base == "current":
+                _display_history(config, script, rev, head, rev)
+            else:
+                _display_history(config, script, base, head, rev)
+            return []
+
+        with EnvironmentContext(config, script, fn=_display_current_history):
+            script.run_env()
+
+    if base == "current" or head == "current" or environment:
+        _display_history_w_current(config, script, base, head)
+    else:
+        _display_history(config, script, base, head)
+
+
+def heads(config, verbose=False, resolve_dependencies=False):
+    """Show current available heads in the script directory.
+
+    :param config: a :class:`.Config` instance.
+
+    :param verbose: output in verbose mode.
+
+    :param resolve_dependencies: treat dependency version as down revisions.
+
+    """
+
+    script = ScriptDirectory.from_config(config)
+    if resolve_dependencies:
+        heads = script.get_revisions("heads")
+    else:
+        heads = script.get_revisions(script.get_heads())
+
+    for rev in heads:
+        config.print_stdout(
+            rev.cmd_format(
+                verbose, include_branches=True, tree_indicators=False
+            )
+        )
+
+
+def branches(config, verbose=False):
+    """Show current branch points.
+
+    :param config: a :class:`.Config` instance.
+
+    :param verbose: output in verbose mode.
+
+    """
+    script = ScriptDirectory.from_config(config)
+    for sc in script.walk_revisions():
+        if sc.is_branch_point:
+            config.print_stdout(
+                "%s\n%s\n",
+                sc.cmd_format(verbose, include_branches=True),
+                "\n".join(
+                    "%s -> %s"
+                    % (
+                        " " * len(str(sc.revision)),
+                        rev_obj.cmd_format(
+                            False, include_branches=True, include_doc=verbose
+                        ),
+                    )
+                    for rev_obj in (
+                        script.get_revision(rev) for rev in sc.nextrev
+                    )
+                ),
+            )
+
+
+def current(config: Config, verbose: bool = False) -> None:
+    """Display the current revision for a database.
+
+    :param config: a :class:`.Config` instance.
+
+    :param verbose: output in verbose mode.
+
+    """
+
+    script = ScriptDirectory.from_config(config)
+
+    def display_version(rev, context):
+        if verbose:
+            config.print_stdout(
+                "Current revision(s) for %s:",
+                util.obfuscate_url_pw(context.connection.engine.url),
+            )
+        for rev in script.get_all_current(rev):
+            config.print_stdout(rev.cmd_format(verbose))
+
+        return []
+
+    with EnvironmentContext(
+        config, script, fn=display_version, dont_mutate=True
+    ):
+        script.run_env()
+
+
+def stamp(
+    config: Config,
+    revision: _RevIdType,
+    sql: bool = False,
+    tag: Optional[str] = None,
+    purge: bool = False,
+) -> None:
+    """'stamp' the revision table with the given revision; don't
+    run any migrations.
+
+    :param config: a :class:`.Config` instance.
+
+    :param revision: target revision or list of revisions.   May be a list
+     to indicate stamping of multiple branch heads.
+
+     .. note:: this parameter is called "revisions" in the command line
+        interface.
+
+    :param sql: use ``--sql`` mode
+
+    :param tag: an arbitrary "tag" that can be intercepted by custom
+     ``env.py`` scripts via the :class:`.EnvironmentContext.get_tag_argument`
+     method.
+
+    :param purge: delete all entries in the version table before stamping.
+
+    """
+
+    script = ScriptDirectory.from_config(config)
+
+    if sql:
+        destination_revs = []
+        starting_rev = None
+        for _revision in util.to_list(revision):
+            if ":" in _revision:
+                srev, _revision = _revision.split(":", 2)
+
+                if starting_rev != srev:
+                    if starting_rev is None:
+                        starting_rev = srev
+                    else:
+                        raise util.CommandError(
+                            "Stamp operation with --sql only supports a "
+                            "single starting revision at a time"
+                        )
+            destination_revs.append(_revision)
+    else:
+        destination_revs = util.to_list(revision)
+
+    def do_stamp(rev, context):
+        return script._stamp_revs(util.to_tuple(destination_revs), rev)
+
+    with EnvironmentContext(
+        config,
+        script,
+        fn=do_stamp,
+        as_sql=sql,
+        starting_rev=starting_rev if sql else None,
+        destination_rev=util.to_tuple(destination_revs),
+        tag=tag,
+        purge=purge,
+    ):
+        script.run_env()
+
+
+def edit(config: Config, rev: str) -> None:
+    """Edit revision script(s) using $EDITOR.
+
+    :param config: a :class:`.Config` instance.
+
+    :param rev: target revision.
+
+    """
+
+    script = ScriptDirectory.from_config(config)
+
+    if rev == "current":
+
+        def edit_current(rev, context):
+            if not rev:
+                raise util.CommandError("No current revisions")
+            for sc in script.get_revisions(rev):
+                util.open_in_editor(sc.path)
+            return []
+
+        with EnvironmentContext(config, script, fn=edit_current):
+            script.run_env()
+    else:
+        revs = script.get_revisions(rev)
+        if not revs:
+            raise util.CommandError(
+                "No revision files indicated by symbol '%s'" % rev
+            )
+        for sc in revs:
+            assert sc
+            util.open_in_editor(sc.path)
+
+
+def ensure_version(config: Config, sql: bool = False) -> None:
+    """Create the alembic version table if it doesn't exist already .
+
+    :param config: a :class:`.Config` instance.
+
+    :param sql: use ``--sql`` mode
+
+     .. versionadded:: 1.7.6
+
+    """
+
+    script = ScriptDirectory.from_config(config)
+
+    def do_ensure_version(rev, context):
+        context._ensure_version_table()
+        return []
+
+    with EnvironmentContext(
+        config,
+        script,
+        fn=do_ensure_version,
+        as_sql=sql,
+    ):
+        script.run_env()

.venv2/Lib/site-packages/alembic/config.py

@@ -0,0 +1,645 @@
+from __future__ import annotations
+
+from argparse import ArgumentParser
+from argparse import Namespace
+from configparser import ConfigParser
+import inspect
+import os
+import sys
+from typing import Any
+from typing import cast
+from typing import Dict
+from typing import Mapping
+from typing import Optional
+from typing import overload
+from typing import Sequence
+from typing import TextIO
+from typing import Union
+
+from typing_extensions import TypedDict
+
+from . import __version__
+from . import command
+from . import util
+from .util import compat
+
+
+class Config:
+    r"""Represent an Alembic configuration.
+
+    Within an ``env.py`` script, this is available
+    via the :attr:`.EnvironmentContext.config` attribute,
+    which in turn is available at ``alembic.context``::
+
+        from alembic import context
+
+        some_param = context.config.get_main_option("my option")
+
+    When invoking Alembic programmatically, a new
+    :class:`.Config` can be created by passing
+    the name of an .ini file to the constructor::
+
+        from alembic.config import Config
+        alembic_cfg = Config("/path/to/yourapp/alembic.ini")
+
+    With a :class:`.Config` object, you can then
+    run Alembic commands programmatically using the directives
+    in :mod:`alembic.command`.
+
+    The :class:`.Config` object can also be constructed without
+    a filename.   Values can be set programmatically, and
+    new sections will be created as needed::
+
+        from alembic.config import Config
+        alembic_cfg = Config()
+        alembic_cfg.set_main_option("script_location", "myapp:migrations")
+        alembic_cfg.set_main_option("sqlalchemy.url", "postgresql://foo/bar")
+        alembic_cfg.set_section_option("mysection", "foo", "bar")
+
+    .. warning::
+
+       When using programmatic configuration, make sure the
+       ``env.py`` file in use is compatible with the target configuration;
+       including that the call to Python ``logging.fileConfig()`` is
+       omitted if the programmatic configuration doesn't actually include
+       logging directives.
+
+    For passing non-string values to environments, such as connections and
+    engines, use the :attr:`.Config.attributes` dictionary::
+
+        with engine.begin() as connection:
+            alembic_cfg.attributes['connection'] = connection
+            command.upgrade(alembic_cfg, "head")
+
+    :param file\_: name of the .ini file to open.
+    :param ini_section: name of the main Alembic section within the
+     .ini file
+    :param output_buffer: optional file-like input buffer which
+     will be passed to the :class:`.MigrationContext` - used to redirect
+     the output of "offline generation" when using Alembic programmatically.
+    :param stdout: buffer where the "print" output of commands will be sent.
+     Defaults to ``sys.stdout``.
+
+    :param config_args: A dictionary of keys and values that will be used
+     for substitution in the alembic config file.  The dictionary as given
+     is **copied** to a new one, stored locally as the attribute
+     ``.config_args``. When the :attr:`.Config.file_config` attribute is
+     first invoked, the replacement variable ``here`` will be added to this
+     dictionary before the dictionary is passed to ``ConfigParser()``
+     to parse the .ini file.
+
+    :param attributes: optional dictionary of arbitrary Python keys/values,
+     which will be populated into the :attr:`.Config.attributes` dictionary.
+
+     .. seealso::
+
+        :ref:`connection_sharing`
+
+    """
+
+    def __init__(
+        self,
+        file_: Union[str, os.PathLike[str], None] = None,
+        ini_section: str = "alembic",
+        output_buffer: Optional[TextIO] = None,
+        stdout: TextIO = sys.stdout,
+        cmd_opts: Optional[Namespace] = None,
+        config_args: Mapping[str, Any] = util.immutabledict(),
+        attributes: Optional[Dict[str, Any]] = None,
+    ) -> None:
+        """Construct a new :class:`.Config`"""
+        self.config_file_name = file_
+        self.config_ini_section = ini_section
+        self.output_buffer = output_buffer
+        self.stdout = stdout
+        self.cmd_opts = cmd_opts
+        self.config_args = dict(config_args)
+        if attributes:
+            self.attributes.update(attributes)
+
+    cmd_opts: Optional[Namespace] = None
+    """The command-line options passed to the ``alembic`` script.
+
+    Within an ``env.py`` script this can be accessed via the
+    :attr:`.EnvironmentContext.config` attribute.
+
+    .. seealso::
+
+        :meth:`.EnvironmentContext.get_x_argument`
+
+    """
+
+    config_file_name: Union[str, os.PathLike[str], None] = None
+    """Filesystem path to the .ini file in use."""
+
+    config_ini_section: str = None  # type:ignore[assignment]
+    """Name of the config file section to read basic configuration
+    from.  Defaults to ``alembic``, that is the ``[alembic]`` section
+    of the .ini file.  This value is modified using the ``-n/--name``
+    option to the Alembic runner.
+
+    """
+
+    @util.memoized_property
+    def attributes(self) -> Dict[str, Any]:
+        """A Python dictionary for storage of additional state.
+
+
+        This is a utility dictionary which can include not just strings but
+        engines, connections, schema objects, or anything else.
+        Use this to pass objects into an env.py script, such as passing
+        a :class:`sqlalchemy.engine.base.Connection` when calling
+        commands from :mod:`alembic.command` programmatically.
+
+        .. seealso::
+
+            :ref:`connection_sharing`
+
+            :paramref:`.Config.attributes`
+
+        """
+        return {}
+
+    def print_stdout(self, text: str, *arg: Any) -> None:
+        """Render a message to standard out.
+
+        When :meth:`.Config.print_stdout` is called with additional args
+        those arguments will formatted against the provided text,
+        otherwise we simply output the provided text verbatim.
+
+        This is a no-op when the``quiet`` messaging option is enabled.
+
+        e.g.::
+
+            >>> config.print_stdout('Some text %s', 'arg')
+            Some Text arg
+
+        """
+
+        if arg:
+            output = str(text) % arg
+        else:
+            output = str(text)
+
+        util.write_outstream(self.stdout, output, "\n", **self.messaging_opts)
+
+    @util.memoized_property
+    def file_config(self) -> ConfigParser:
+        """Return the underlying ``ConfigParser`` object.
+
+        Direct access to the .ini file is available here,
+        though the :meth:`.Config.get_section` and
+        :meth:`.Config.get_main_option`
+        methods provide a possibly simpler interface.
+
+        """
+
+        if self.config_file_name:
+            here = os.path.abspath(os.path.dirname(self.config_file_name))
+        else:
+            here = ""
+        self.config_args["here"] = here
+        file_config = ConfigParser(self.config_args)
+        if self.config_file_name:
+            compat.read_config_parser(file_config, [self.config_file_name])
+        else:
+            file_config.add_section(self.config_ini_section)
+        return file_config
+
+    def get_template_directory(self) -> str:
+        """Return the directory where Alembic setup templates are found.
+
+        This method is used by the alembic ``init`` and ``list_templates``
+        commands.
+
+        """
+        import alembic
+
+        package_dir = os.path.abspath(os.path.dirname(alembic.__file__))
+        return os.path.join(package_dir, "templates")
+
+    @overload
+    def get_section(
+        self, name: str, default: None = ...
+    ) -> Optional[Dict[str, str]]:
+        ...
+
+    # "default" here could also be a TypeVar
+    # _MT = TypeVar("_MT", bound=Mapping[str, str]),
+    # however mypy wasn't handling that correctly (pyright was)
+    @overload
+    def get_section(
+        self, name: str, default: Dict[str, str]
+    ) -> Dict[str, str]:
+        ...
+
+    @overload
+    def get_section(
+        self, name: str, default: Mapping[str, str]
+    ) -> Union[Dict[str, str], Mapping[str, str]]:
+        ...
+
+    def get_section(
+        self, name: str, default: Optional[Mapping[str, str]] = None
+    ) -> Optional[Mapping[str, str]]:
+        """Return all the configuration options from a given .ini file section
+        as a dictionary.
+
+        If the given section does not exist, the value of ``default``
+        is returned, which is expected to be a dictionary or other mapping.
+
+        """
+        if not self.file_config.has_section(name):
+            return default
+
+        return dict(self.file_config.items(name))
+
+    def set_main_option(self, name: str, value: str) -> None:
+        """Set an option programmatically within the 'main' section.
+
+        This overrides whatever was in the .ini file.
+
+        :param name: name of the value
+
+        :param value: the value.  Note that this value is passed to
+         ``ConfigParser.set``, which supports variable interpolation using
+         pyformat (e.g. ``%(some_value)s``).   A raw percent sign not part of
+         an interpolation symbol must therefore be escaped, e.g. ``%%``.
+         The given value may refer to another value already in the file
+         using the interpolation format.
+
+        """
+        self.set_section_option(self.config_ini_section, name, value)
+
+    def remove_main_option(self, name: str) -> None:
+        self.file_config.remove_option(self.config_ini_section, name)
+
+    def set_section_option(self, section: str, name: str, value: str) -> None:
+        """Set an option programmatically within the given section.
+
+        The section is created if it doesn't exist already.
+        The value here will override whatever was in the .ini
+        file.
+
+        :param section: name of the section
+
+        :param name: name of the value
+
+        :param value: the value.  Note that this value is passed to
+         ``ConfigParser.set``, which supports variable interpolation using
+         pyformat (e.g. ``%(some_value)s``).   A raw percent sign not part of
+         an interpolation symbol must therefore be escaped, e.g. ``%%``.
+         The given value may refer to another value already in the file
+         using the interpolation format.
+
+        """
+
+        if not self.file_config.has_section(section):
+            self.file_config.add_section(section)
+        self.file_config.set(section, name, value)
+
+    def get_section_option(
+        self, section: str, name: str, default: Optional[str] = None
+    ) -> Optional[str]:
+        """Return an option from the given section of the .ini file."""
+        if not self.file_config.has_section(section):
+            raise util.CommandError(
+                "No config file %r found, or file has no "
+                "'[%s]' section" % (self.config_file_name, section)
+            )
+        if self.file_config.has_option(section, name):
+            return self.file_config.get(section, name)
+        else:
+            return default
+
+    @overload
+    def get_main_option(self, name: str, default: str) -> str:
+        ...
+
+    @overload
+    def get_main_option(
+        self, name: str, default: Optional[str] = None
+    ) -> Optional[str]:
+        ...
+
+    def get_main_option(
+        self, name: str, default: Optional[str] = None
+    ) -> Optional[str]:
+        """Return an option from the 'main' section of the .ini file.
+
+        This defaults to being a key from the ``[alembic]``
+        section, unless the ``-n/--name`` flag were used to
+        indicate a different section.
+
+        """
+        return self.get_section_option(self.config_ini_section, name, default)
+
+    @util.memoized_property
+    def messaging_opts(self) -> MessagingOptions:
+        """The messaging options."""
+        return cast(
+            MessagingOptions,
+            util.immutabledict(
+                {"quiet": getattr(self.cmd_opts, "quiet", False)}
+            ),
+        )
+
+
+class MessagingOptions(TypedDict, total=False):
+    quiet: bool
+
+
+class CommandLine:
+    def __init__(self, prog: Optional[str] = None) -> None:
+        self._generate_args(prog)
+
+    def _generate_args(self, prog: Optional[str]) -> None:
+        def add_options(
+            fn: Any, parser: Any, positional: Any, kwargs: Any
+        ) -> None:
+            kwargs_opts = {
+                "template": (
+                    "-t",
+                    "--template",
+                    dict(
+                        default="generic",
+                        type=str,
+                        help="Setup template for use with 'init'",
+                    ),
+                ),
+                "message": (
+                    "-m",
+                    "--message",
+                    dict(
+                        type=str, help="Message string to use with 'revision'"
+                    ),
+                ),
+                "sql": (
+                    "--sql",
+                    dict(
+                        action="store_true",
+                        help="Don't emit SQL to database - dump to "
+                        "standard output/file instead. See docs on "
+                        "offline mode.",
+                    ),
+                ),
+                "tag": (
+                    "--tag",
+                    dict(
+                        type=str,
+                        help="Arbitrary 'tag' name - can be used by "
+                        "custom env.py scripts.",
+                    ),
+                ),
+                "head": (
+                    "--head",
+                    dict(
+                        type=str,
+                        help="Specify head revision or <branchname>@head "
+                        "to base new revision on.",
+                    ),
+                ),
+                "splice": (
+                    "--splice",
+                    dict(
+                        action="store_true",
+                        help="Allow a non-head revision as the "
+                        "'head' to splice onto",
+                    ),
+                ),
+                "depends_on": (
+                    "--depends-on",
+                    dict(
+                        action="append",
+                        help="Specify one or more revision identifiers "
+                        "which this revision should depend on.",
+                    ),
+                ),
+                "rev_id": (
+                    "--rev-id",
+                    dict(
+                        type=str,
+                        help="Specify a hardcoded revision id instead of "
+                        "generating one",
+                    ),
+                ),
+                "version_path": (
+                    "--version-path",
+                    dict(
+                        type=str,
+                        help="Specify specific path from config for "
+                        "version file",
+                    ),
+                ),
+                "branch_label": (
+                    "--branch-label",
+                    dict(
+                        type=str,
+                        help="Specify a branch label to apply to the "
+                        "new revision",
+                    ),
+                ),
+                "verbose": (
+                    "-v",
+                    "--verbose",
+                    dict(action="store_true", help="Use more verbose output"),
+                ),
+                "resolve_dependencies": (
+                    "--resolve-dependencies",
+                    dict(
+                        action="store_true",
+                        help="Treat dependency versions as down revisions",
+                    ),
+                ),
+                "autogenerate": (
+                    "--autogenerate",
+                    dict(
+                        action="store_true",
+                        help="Populate revision script with candidate "
+                        "migration operations, based on comparison "
+                        "of database to model.",
+                    ),
+                ),
+                "rev_range": (
+                    "-r",
+                    "--rev-range",
+                    dict(
+                        action="store",
+                        help="Specify a revision range; "
+                        "format is [start]:[end]",
+                    ),
+                ),
+                "indicate_current": (
+                    "-i",
+                    "--indicate-current",
+                    dict(
+                        action="store_true",
+                        help="Indicate the current revision",
+                    ),
+                ),
+                "purge": (
+                    "--purge",
+                    dict(
+                        action="store_true",
+                        help="Unconditionally erase the version table "
+                        "before stamping",
+                    ),
+                ),
+                "package": (
+                    "--package",
+                    dict(
+                        action="store_true",
+                        help="Write empty __init__.py files to the "
+                        "environment and version locations",
+                    ),
+                ),
+            }
+            positional_help = {
+                "directory": "location of scripts directory",
+                "revision": "revision identifier",
+                "revisions": "one or more revisions, or 'heads' for all heads",
+            }
+            for arg in kwargs:
+                if arg in kwargs_opts:
+                    args = kwargs_opts[arg]
+                    args, kw = args[0:-1], args[-1]
+                    parser.add_argument(*args, **kw)
+
+            for arg in positional:
+                if (
+                    arg == "revisions"
+                    or fn in positional_translations
+                    and positional_translations[fn][arg] == "revisions"
+                ):
+                    subparser.add_argument(
+                        "revisions",
+                        nargs="+",
+                        help=positional_help.get("revisions"),
+                    )
+                else:
+                    subparser.add_argument(arg, help=positional_help.get(arg))
+
+        parser = ArgumentParser(prog=prog)
+
+        parser.add_argument(
+            "--version", action="version", version="%%(prog)s %s" % __version__
+        )
+        parser.add_argument(
+            "-c",
+            "--config",
+            type=str,
+            default=os.environ.get("ALEMBIC_CONFIG", "alembic.ini"),
+            help="Alternate config file; defaults to value of "
+            'ALEMBIC_CONFIG environment variable, or "alembic.ini"',
+        )
+        parser.add_argument(
+            "-n",
+            "--name",
+            type=str,
+            default="alembic",
+            help="Name of section in .ini file to " "use for Alembic config",
+        )
+        parser.add_argument(
+            "-x",
+            action="append",
+            help="Additional arguments consumed by "
+            "custom env.py scripts, e.g. -x "
+            "setting1=somesetting -x setting2=somesetting",
+        )
+        parser.add_argument(
+            "--raiseerr",
+            action="store_true",
+            help="Raise a full stack trace on error",
+        )
+        parser.add_argument(
+            "-q",
+            "--quiet",
+            action="store_true",
+            help="Do not log to std output.",
+        )
+        subparsers = parser.add_subparsers()
+
+        positional_translations: Dict[Any, Any] = {
+            command.stamp: {"revision": "revisions"}
+        }
+
+        for fn in [getattr(command, n) for n in dir(command)]:
+            if (
+                inspect.isfunction(fn)
+                and fn.__name__[0] != "_"
+                and fn.__module__ == "alembic.command"
+            ):
+                spec = compat.inspect_getfullargspec(fn)
+                if spec[3] is not None:
+                    positional = spec[0][1 : -len(spec[3])]
+                    kwarg = spec[0][-len(spec[3]) :]
+                else:
+                    positional = spec[0][1:]
+                    kwarg = []
+
+                if fn in positional_translations:
+                    positional = [
+                        positional_translations[fn].get(name, name)
+                        for name in positional
+                    ]
+
+                # parse first line(s) of helptext without a line break
+                help_ = fn.__doc__
+                if help_:
+                    help_text = []
+                    for line in help_.split("\n"):
+                        if not line.strip():
+                            break
+                        else:
+                            help_text.append(line.strip())
+                else:
+                    help_text = []
+                subparser = subparsers.add_parser(
+                    fn.__name__, help=" ".join(help_text)
+                )
+                add_options(fn, subparser, positional, kwarg)
+                subparser.set_defaults(cmd=(fn, positional, kwarg))
+        self.parser = parser
+
+    def run_cmd(self, config: Config, options: Namespace) -> None:
+        fn, positional, kwarg = options.cmd
+
+        try:
+            fn(
+                config,
+                *[getattr(options, k, None) for k in positional],
+                **{k: getattr(options, k, None) for k in kwarg},
+            )
+        except util.CommandError as e:
+            if options.raiseerr:
+                raise
+            else:
+                util.err(str(e), **config.messaging_opts)
+
+    def main(self, argv: Optional[Sequence[str]] = None) -> None:
+        options = self.parser.parse_args(argv)
+        if not hasattr(options, "cmd"):
+            # see http://bugs.python.org/issue9253, argparse
+            # behavior changed incompatibly in py3.3
+            self.parser.error("too few arguments")
+        else:
+            cfg = Config(
+                file_=options.config,
+                ini_section=options.name,
+                cmd_opts=options,
+            )
+            self.run_cmd(cfg, options)
+
+
+def main(
+    argv: Optional[Sequence[str]] = None,
+    prog: Optional[str] = None,
+    **kwargs: Any,
+) -> None:
+    """The console runner function for Alembic."""
+
+    CommandLine(prog=prog).main(argv=argv)
+
+
+if __name__ == "__main__":
+    main()

.venv2/Lib/site-packages/alembic/context.py

@@ -0,0 +1,5 @@
+from .runtime.environment import EnvironmentContext
+
+# create proxy functions for
+# each method on the EnvironmentContext class.
+EnvironmentContext.create_module_class_proxy(globals(), locals())

.venv2/Lib/site-packages/alembic/context.pyi

@@ -0,0 +1,853 @@
+# ### this file stubs are generated by tools/write_pyi.py - do not edit ###
+# ### imports are manually managed
+from __future__ import annotations
+
+from typing import Any
+from typing import Callable
+from typing import Collection
+from typing import ContextManager
+from typing import Dict
+from typing import Iterable
+from typing import List
+from typing import Literal
+from typing import Mapping
+from typing import MutableMapping
+from typing import Optional
+from typing import overload
+from typing import Sequence
+from typing import TextIO
+from typing import Tuple
+from typing import TYPE_CHECKING
+from typing import Union
+
+if TYPE_CHECKING:
+    from sqlalchemy.engine.base import Connection
+    from sqlalchemy.engine.url import URL
+    from sqlalchemy.sql import Executable
+    from sqlalchemy.sql.schema import Column
+    from sqlalchemy.sql.schema import FetchedValue
+    from sqlalchemy.sql.schema import MetaData
+    from sqlalchemy.sql.schema import SchemaItem
+    from sqlalchemy.sql.type_api import TypeEngine
+
+    from .autogenerate.api import AutogenContext
+    from .config import Config
+    from .operations.ops import MigrationScript
+    from .runtime.migration import _ProxyTransaction
+    from .runtime.migration import MigrationContext
+    from .runtime.migration import MigrationInfo
+    from .script import ScriptDirectory
+
+### end imports ###
+
+def begin_transaction() -> Union[_ProxyTransaction, ContextManager[None]]:
+    """Return a context manager that will
+    enclose an operation within a "transaction",
+    as defined by the environment's offline
+    and transactional DDL settings.
+
+    e.g.::
+
+        with context.begin_transaction():
+            context.run_migrations()
+
+    :meth:`.begin_transaction` is intended to
+    "do the right thing" regardless of
+    calling context:
+
+    * If :meth:`.is_transactional_ddl` is ``False``,
+      returns a "do nothing" context manager
+      which otherwise produces no transactional
+      state or directives.
+    * If :meth:`.is_offline_mode` is ``True``,
+      returns a context manager that will
+      invoke the :meth:`.DefaultImpl.emit_begin`
+      and :meth:`.DefaultImpl.emit_commit`
+      methods, which will produce the string
+      directives ``BEGIN`` and ``COMMIT`` on
+      the output stream, as rendered by the
+      target backend (e.g. SQL Server would
+      emit ``BEGIN TRANSACTION``).
+    * Otherwise, calls :meth:`sqlalchemy.engine.Connection.begin`
+      on the current online connection, which
+      returns a :class:`sqlalchemy.engine.Transaction`
+      object.  This object demarcates a real
+      transaction and is itself a context manager,
+      which will roll back if an exception
+      is raised.
+
+    Note that a custom ``env.py`` script which
+    has more specific transactional needs can of course
+    manipulate the :class:`~sqlalchemy.engine.Connection`
+    directly to produce transactional state in "online"
+    mode.
+
+    """
+
+config: Config
+
+def configure(
+    connection: Optional[Connection] = None,
+    url: Union[str, URL, None] = None,
+    dialect_name: Optional[str] = None,
+    dialect_opts: Optional[Dict[str, Any]] = None,
+    transactional_ddl: Optional[bool] = None,
+    transaction_per_migration: bool = False,
+    output_buffer: Optional[TextIO] = None,
+    starting_rev: Optional[str] = None,
+    tag: Optional[str] = None,
+    template_args: Optional[Dict[str, Any]] = None,
+    render_as_batch: bool = False,
+    target_metadata: Union[MetaData, Sequence[MetaData], None] = None,
+    include_name: Optional[
+        Callable[
+            [
+                Optional[str],
+                Literal[
+                    "schema",
+                    "table",
+                    "column",
+                    "index",
+                    "unique_constraint",
+                    "foreign_key_constraint",
+                ],
+                MutableMapping[
+                    Literal[
+                        "schema_name",
+                        "table_name",
+                        "schema_qualified_table_name",
+                    ],
+                    Optional[str],
+                ],
+            ],
+            bool,
+        ]
+    ] = None,
+    include_object: Optional[
+        Callable[
+            [
+                SchemaItem,
+                Optional[str],
+                Literal[
+                    "schema",
+                    "table",
+                    "column",
+                    "index",
+                    "unique_constraint",
+                    "foreign_key_constraint",
+                ],
+                bool,
+                Optional[SchemaItem],
+            ],
+            bool,
+        ]
+    ] = None,
+    include_schemas: bool = False,
+    process_revision_directives: Optional[
+        Callable[
+            [
+                MigrationContext,
+                Union[str, Iterable[Optional[str]], Iterable[str]],
+                List[MigrationScript],
+            ],
+            None,
+        ]
+    ] = None,
+    compare_type: Union[
+        bool,
+        Callable[
+            [
+                MigrationContext,
+                Column[Any],
+                Column[Any],
+                TypeEngine[Any],
+                TypeEngine[Any],
+            ],
+            Optional[bool],
+        ],
+    ] = True,
+    compare_server_default: Union[
+        bool,
+        Callable[
+            [
+                MigrationContext,
+                Column[Any],
+                Column[Any],
+                Optional[str],
+                Optional[FetchedValue],
+                Optional[str],
+            ],
+            Optional[bool],
+        ],
+    ] = False,
+    render_item: Optional[
+        Callable[[str, Any, AutogenContext], Union[str, Literal[False]]]
+    ] = None,
+    literal_binds: bool = False,
+    upgrade_token: str = "upgrades",
+    downgrade_token: str = "downgrades",
+    alembic_module_prefix: str = "op.",
+    sqlalchemy_module_prefix: str = "sa.",
+    user_module_prefix: Optional[str] = None,
+    on_version_apply: Optional[
+        Callable[
+            [
+                MigrationContext,
+                MigrationInfo,
+                Collection[Any],
+                Mapping[str, Any],
+            ],
+            None,
+        ]
+    ] = None,
+    **kw: Any,
+) -> None:
+    """Configure a :class:`.MigrationContext` within this
+    :class:`.EnvironmentContext` which will provide database
+    connectivity and other configuration to a series of
+    migration scripts.
+
+    Many methods on :class:`.EnvironmentContext` require that
+    this method has been called in order to function, as they
+    ultimately need to have database access or at least access
+    to the dialect in use.  Those which do are documented as such.
+
+    The important thing needed by :meth:`.configure` is a
+    means to determine what kind of database dialect is in use.
+    An actual connection to that database is needed only if
+    the :class:`.MigrationContext` is to be used in
+    "online" mode.
+
+    If the :meth:`.is_offline_mode` function returns ``True``,
+    then no connection is needed here.  Otherwise, the
+    ``connection`` parameter should be present as an
+    instance of :class:`sqlalchemy.engine.Connection`.
+
+    This function is typically called from the ``env.py``
+    script within a migration environment.  It can be called
+    multiple times for an invocation.  The most recent
+    :class:`~sqlalchemy.engine.Connection`
+    for which it was called is the one that will be operated upon
+    by the next call to :meth:`.run_migrations`.
+
+    General parameters:
+
+    :param connection: a :class:`~sqlalchemy.engine.Connection`
+     to use
+     for SQL execution in "online" mode.  When present, is also
+     used to determine the type of dialect in use.
+    :param url: a string database url, or a
+     :class:`sqlalchemy.engine.url.URL` object.
+     The type of dialect to be used will be derived from this if
+     ``connection`` is not passed.
+    :param dialect_name: string name of a dialect, such as
+     "postgresql", "mssql", etc.
+     The type of dialect to be used will be derived from this if
+     ``connection`` and ``url`` are not passed.
+    :param dialect_opts: dictionary of options to be passed to dialect
+     constructor.
+    :param transactional_ddl: Force the usage of "transactional"
+     DDL on or off;
+     this otherwise defaults to whether or not the dialect in
+     use supports it.
+    :param transaction_per_migration: if True, nest each migration script
+     in a transaction rather than the full series of migrations to
+     run.
+    :param output_buffer: a file-like object that will be used
+     for textual output
+     when the ``--sql`` option is used to generate SQL scripts.
+     Defaults to
+     ``sys.stdout`` if not passed here and also not present on
+     the :class:`.Config`
+     object.  The value here overrides that of the :class:`.Config`
+     object.
+    :param output_encoding: when using ``--sql`` to generate SQL
+     scripts, apply this encoding to the string output.
+    :param literal_binds: when using ``--sql`` to generate SQL
+     scripts, pass through the ``literal_binds`` flag to the compiler
+     so that any literal values that would ordinarily be bound
+     parameters are converted to plain strings.
+
+     .. warning:: Dialects can typically only handle simple datatypes
+        like strings and numbers for auto-literal generation.  Datatypes
+        like dates, intervals, and others may still require manual
+        formatting, typically using :meth:`.Operations.inline_literal`.
+
+     .. note:: the ``literal_binds`` flag is ignored on SQLAlchemy
+        versions prior to 0.8 where this feature is not supported.
+
+     .. seealso::
+
+        :meth:`.Operations.inline_literal`
+
+    :param starting_rev: Override the "starting revision" argument
+     when using ``--sql`` mode.
+    :param tag: a string tag for usage by custom ``env.py`` scripts.
+     Set via the ``--tag`` option, can be overridden here.
+    :param template_args: dictionary of template arguments which
+     will be added to the template argument environment when
+     running the "revision" command.   Note that the script environment
+     is only run within the "revision" command if the --autogenerate
+     option is used, or if the option "revision_environment=true"
+     is present in the alembic.ini file.
+
+    :param version_table: The name of the Alembic version table.
+     The default is ``'alembic_version'``.
+    :param version_table_schema: Optional schema to place version
+     table within.
+    :param version_table_pk: boolean, whether the Alembic version table
+     should use a primary key constraint for the "value" column; this
+     only takes effect when the table is first created.
+     Defaults to True; setting to False should not be necessary and is
+     here for backwards compatibility reasons.
+    :param on_version_apply: a callable or collection of callables to be
+        run for each migration step.
+        The callables will be run in the order they are given, once for
+        each migration step, after the respective operation has been
+        applied but before its transaction is finalized.
+        Each callable accepts no positional arguments and the following
+        keyword arguments:
+
+        * ``ctx``: the :class:`.MigrationContext` running the migration,
+        * ``step``: a :class:`.MigrationInfo` representing the
+          step currently being applied,
+        * ``heads``: a collection of version strings representing the
+          current heads,
+        * ``run_args``: the ``**kwargs`` passed to :meth:`.run_migrations`.
+
+    Parameters specific to the autogenerate feature, when
+    ``alembic revision`` is run with the ``--autogenerate`` feature:
+
+    :param target_metadata: a :class:`sqlalchemy.schema.MetaData`
+     object, or a sequence of :class:`~sqlalchemy.schema.MetaData`
+     objects, that will be consulted during autogeneration.
+     The tables present in each :class:`~sqlalchemy.schema.MetaData`
+     will be compared against
+     what is locally available on the target
+     :class:`~sqlalchemy.engine.Connection`
+     to produce candidate upgrade/downgrade operations.
+    :param compare_type: Indicates type comparison behavior during
+     an autogenerate
+     operation.  Defaults to ``True`` turning on type comparison, which
+     has good accuracy on most backends.   See :ref:`compare_types`
+     for an example as well as information on other type
+     comparison options. Set to ``False`` which disables type
+     comparison. A callable can also be passed to provide custom type
+     comparison, see :ref:`compare_types` for additional details.
+
+     .. versionchanged:: 1.12.0 The default value of
+        :paramref:`.EnvironmentContext.configure.compare_type` has been
+        changed to ``True``.
+
+     .. seealso::
+
+        :ref:`compare_types`
+
+        :paramref:`.EnvironmentContext.configure.compare_server_default`
+
+    :param compare_server_default: Indicates server default comparison
+     behavior during
+     an autogenerate operation.  Defaults to ``False`` which disables
+     server default
+     comparison.  Set to  ``True`` to turn on server default comparison,
+     which has
+     varied accuracy depending on backend.
+
+     To customize server default comparison behavior, a callable may
+     be specified
+     which can filter server default comparisons during an
+     autogenerate operation.
+     defaults during an autogenerate operation.   The format of this
+     callable is::
+
+        def my_compare_server_default(context, inspected_column,
+                    metadata_column, inspected_default, metadata_default,
+                    rendered_metadata_default):
+            # return True if the defaults are different,
+            # False if not, or None to allow the default implementation
+            # to compare these defaults
+            return None
+
+        context.configure(
+            # ...
+            compare_server_default = my_compare_server_default
+        )
+
+     ``inspected_column`` is a dictionary structure as returned by
+     :meth:`sqlalchemy.engine.reflection.Inspector.get_columns`, whereas
+     ``metadata_column`` is a :class:`sqlalchemy.schema.Column` from
+     the local model environment.
+
+     A return value of ``None`` indicates to allow default server default
+     comparison
+     to proceed.  Note that some backends such as Postgresql actually
+     execute
+     the two defaults on the database side to compare for equivalence.
+
+     .. seealso::
+
+        :paramref:`.EnvironmentContext.configure.compare_type`
+
+    :param include_name: A callable function which is given
+     the chance to return ``True`` or ``False`` for any database reflected
+     object based on its name, including database schema names when
+     the :paramref:`.EnvironmentContext.configure.include_schemas` flag
+     is set to ``True``.
+
+     The function accepts the following positional arguments:
+
+     * ``name``: the name of the object, such as schema name or table name.
+       Will be ``None`` when indicating the default schema name of the
+       database connection.
+     * ``type``: a string describing the type of object; currently
+       ``"schema"``, ``"table"``, ``"column"``, ``"index"``,
+       ``"unique_constraint"``, or ``"foreign_key_constraint"``
+     * ``parent_names``: a dictionary of "parent" object names, that are
+       relative to the name being given.  Keys in this dictionary may
+       include:  ``"schema_name"``, ``"table_name"`` or
+       ``"schema_qualified_table_name"``.
+
+     E.g.::
+
+        def include_name(name, type_, parent_names):
+            if type_ == "schema":
+                return name in ["schema_one", "schema_two"]
+            else:
+                return True
+
+        context.configure(
+            # ...
+            include_schemas = True,
+            include_name = include_name
+        )
+
+     .. seealso::
+
+        :ref:`autogenerate_include_hooks`
+
+        :paramref:`.EnvironmentContext.configure.include_object`
+
+        :paramref:`.EnvironmentContext.configure.include_schemas`
+
+
+    :param include_object: A callable function which is given
+     the chance to return ``True`` or ``False`` for any object,
+     indicating if the given object should be considered in the
+     autogenerate sweep.
+
+     The function accepts the following positional arguments:
+
+     * ``object``: a :class:`~sqlalchemy.schema.SchemaItem` object such
+       as a :class:`~sqlalchemy.schema.Table`,
+       :class:`~sqlalchemy.schema.Column`,
+       :class:`~sqlalchemy.schema.Index`
+       :class:`~sqlalchemy.schema.UniqueConstraint`,
+       or :class:`~sqlalchemy.schema.ForeignKeyConstraint` object
+     * ``name``: the name of the object. This is typically available
+       via ``object.name``.
+     * ``type``: a string describing the type of object; currently
+       ``"table"``, ``"column"``, ``"index"``, ``"unique_constraint"``,
+       or ``"foreign_key_constraint"``
+     * ``reflected``: ``True`` if the given object was produced based on
+       table reflection, ``False`` if it's from a local :class:`.MetaData`
+       object.
+     * ``compare_to``: the object being compared against, if available,
+       else ``None``.
+
+     E.g.::
+
+        def include_object(object, name, type_, reflected, compare_to):
+            if (type_ == "column" and
+                not reflected and
+                object.info.get("skip_autogenerate", False)):
+                return False
+            else:
+                return True
+
+        context.configure(
+            # ...
+            include_object = include_object
+        )
+
+     For the use case of omitting specific schemas from a target database
+     when :paramref:`.EnvironmentContext.configure.include_schemas` is
+     set to ``True``, the :attr:`~sqlalchemy.schema.Table.schema`
+     attribute can be checked for each :class:`~sqlalchemy.schema.Table`
+     object passed to the hook, however it is much more efficient
+     to filter on schemas before reflection of objects takes place
+     using the :paramref:`.EnvironmentContext.configure.include_name`
+     hook.
+
+     .. seealso::
+
+        :ref:`autogenerate_include_hooks`
+
+        :paramref:`.EnvironmentContext.configure.include_name`
+
+        :paramref:`.EnvironmentContext.configure.include_schemas`
+
+    :param render_as_batch: if True, commands which alter elements
+     within a table will be placed under a ``with batch_alter_table():``
+     directive, so that batch migrations will take place.
+
+     .. seealso::
+
+        :ref:`batch_migrations`
+
+    :param include_schemas: If True, autogenerate will scan across
+     all schemas located by the SQLAlchemy
+     :meth:`~sqlalchemy.engine.reflection.Inspector.get_schema_names`
+     method, and include all differences in tables found across all
+     those schemas.  When using this option, you may want to also
+     use the :paramref:`.EnvironmentContext.configure.include_name`
+     parameter to specify a callable which
+     can filter the tables/schemas that get included.
+
+     .. seealso::
+
+        :ref:`autogenerate_include_hooks`
+
+        :paramref:`.EnvironmentContext.configure.include_name`
+
+        :paramref:`.EnvironmentContext.configure.include_object`
+
+    :param render_item: Callable that can be used to override how
+     any schema item, i.e. column, constraint, type,
+     etc., is rendered for autogenerate.  The callable receives a
+     string describing the type of object, the object, and
+     the autogen context.  If it returns False, the
+     default rendering method will be used.  If it returns None,
+     the item will not be rendered in the context of a Table
+     construct, that is, can be used to skip columns or constraints
+     within op.create_table()::
+
+        def my_render_column(type_, col, autogen_context):
+            if type_ == "column" and isinstance(col, MySpecialCol):
+                return repr(col)
+            else:
+                return False
+
+        context.configure(
+            # ...
+            render_item = my_render_column
+        )
+
+     Available values for the type string include: ``"column"``,
+     ``"primary_key"``, ``"foreign_key"``, ``"unique"``, ``"check"``,
+     ``"type"``, ``"server_default"``.
+
+     .. seealso::
+
+        :ref:`autogen_render_types`
+
+    :param upgrade_token: When autogenerate completes, the text of the
+     candidate upgrade operations will be present in this template
+     variable when ``script.py.mako`` is rendered.  Defaults to
+     ``upgrades``.
+    :param downgrade_token: When autogenerate completes, the text of the
+     candidate downgrade operations will be present in this
+     template variable when ``script.py.mako`` is rendered.  Defaults to
+     ``downgrades``.
+
+    :param alembic_module_prefix: When autogenerate refers to Alembic
+     :mod:`alembic.operations` constructs, this prefix will be used
+     (i.e. ``op.create_table``)  Defaults to "``op.``".
+     Can be ``None`` to indicate no prefix.
+
+    :param sqlalchemy_module_prefix: When autogenerate refers to
+     SQLAlchemy
+     :class:`~sqlalchemy.schema.Column` or type classes, this prefix
+     will be used
+     (i.e. ``sa.Column("somename", sa.Integer)``)  Defaults to "``sa.``".
+     Can be ``None`` to indicate no prefix.
+     Note that when dialect-specific types are rendered, autogenerate
+     will render them using the dialect module name, i.e. ``mssql.BIT()``,
+     ``postgresql.UUID()``.
+
+    :param user_module_prefix: When autogenerate refers to a SQLAlchemy
+     type (e.g. :class:`.TypeEngine`) where the module name is not
+     under the ``sqlalchemy`` namespace, this prefix will be used
+     within autogenerate.  If left at its default of
+     ``None``, the ``__module__`` attribute of the type is used to
+     render the import module.   It's a good practice to set this
+     and to have all custom types be available from a fixed module space,
+     in order to future-proof migration files against reorganizations
+     in modules.
+
+     .. seealso::
+
+        :ref:`autogen_module_prefix`
+
+    :param process_revision_directives: a callable function that will
+     be passed a structure representing the end result of an autogenerate
+     or plain "revision" operation, which can be manipulated to affect
+     how the ``alembic revision`` command ultimately outputs new
+     revision scripts.   The structure of the callable is::
+
+        def process_revision_directives(context, revision, directives):
+            pass
+
+     The ``directives`` parameter is a Python list containing
+     a single :class:`.MigrationScript` directive, which represents
+     the revision file to be generated.    This list as well as its
+     contents may be freely modified to produce any set of commands.
+     The section :ref:`customizing_revision` shows an example of
+     doing this.  The ``context`` parameter is the
+     :class:`.MigrationContext` in use,
+     and ``revision`` is a tuple of revision identifiers representing the
+     current revision of the database.
+
+     The callable is invoked at all times when the ``--autogenerate``
+     option is passed to ``alembic revision``.  If ``--autogenerate``
+     is not passed, the callable is invoked only if the
+     ``revision_environment`` variable is set to True in the Alembic
+     configuration, in which case the given ``directives`` collection
+     will contain empty :class:`.UpgradeOps` and :class:`.DowngradeOps`
+     collections for ``.upgrade_ops`` and ``.downgrade_ops``.  The
+     ``--autogenerate`` option itself can be inferred by inspecting
+     ``context.config.cmd_opts.autogenerate``.
+
+     The callable function may optionally be an instance of
+     a :class:`.Rewriter` object.  This is a helper object that
+     assists in the production of autogenerate-stream rewriter functions.
+
+     .. seealso::
+
+         :ref:`customizing_revision`
+
+         :ref:`autogen_rewriter`
+
+         :paramref:`.command.revision.process_revision_directives`
+
+    Parameters specific to individual backends:
+
+    :param mssql_batch_separator: The "batch separator" which will
+     be placed between each statement when generating offline SQL Server
+     migrations.  Defaults to ``GO``.  Note this is in addition to the
+     customary semicolon ``;`` at the end of each statement; SQL Server
+     considers the "batch separator" to denote the end of an
+     individual statement execution, and cannot group certain
+     dependent operations in one step.
+    :param oracle_batch_separator: The "batch separator" which will
+     be placed between each statement when generating offline
+     Oracle migrations.  Defaults to ``/``.  Oracle doesn't add a
+     semicolon between statements like most other backends.
+
+    """
+
+def execute(
+    sql: Union[Executable, str],
+    execution_options: Optional[Dict[str, Any]] = None,
+) -> None:
+    """Execute the given SQL using the current change context.
+
+    The behavior of :meth:`.execute` is the same
+    as that of :meth:`.Operations.execute`.  Please see that
+    function's documentation for full detail including
+    caveats and limitations.
+
+    This function requires that a :class:`.MigrationContext` has
+    first been made available via :meth:`.configure`.
+
+    """
+
+def get_bind() -> Connection:
+    """Return the current 'bind'.
+
+    In "online" mode, this is the
+    :class:`sqlalchemy.engine.Connection` currently being used
+    to emit SQL to the database.
+
+    This function requires that a :class:`.MigrationContext`
+    has first been made available via :meth:`.configure`.
+
+    """
+
+def get_context() -> MigrationContext:
+    """Return the current :class:`.MigrationContext` object.
+
+    If :meth:`.EnvironmentContext.configure` has not been
+    called yet, raises an exception.
+
+    """
+
+def get_head_revision() -> Union[str, Tuple[str, ...], None]:
+    """Return the hex identifier of the 'head' script revision.
+
+    If the script directory has multiple heads, this
+    method raises a :class:`.CommandError`;
+    :meth:`.EnvironmentContext.get_head_revisions` should be preferred.
+
+    This function does not require that the :class:`.MigrationContext`
+    has been configured.
+
+    .. seealso:: :meth:`.EnvironmentContext.get_head_revisions`
+
+    """
+
+def get_head_revisions() -> Union[str, Tuple[str, ...], None]:
+    """Return the hex identifier of the 'heads' script revision(s).
+
+    This returns a tuple containing the version number of all
+    heads in the script directory.
+
+    This function does not require that the :class:`.MigrationContext`
+    has been configured.
+
+    """
+
+def get_revision_argument() -> Union[str, Tuple[str, ...], None]:
+    """Get the 'destination' revision argument.
+
+    This is typically the argument passed to the
+    ``upgrade`` or ``downgrade`` command.
+
+    If it was specified as ``head``, the actual
+    version number is returned; if specified
+    as ``base``, ``None`` is returned.
+
+    This function does not require that the :class:`.MigrationContext`
+    has been configured.
+
+    """
+
+def get_starting_revision_argument() -> Union[str, Tuple[str, ...], None]:
+    """Return the 'starting revision' argument,
+    if the revision was passed using ``start:end``.
+
+    This is only meaningful in "offline" mode.
+    Returns ``None`` if no value is available
+    or was configured.
+
+    This function does not require that the :class:`.MigrationContext`
+    has been configured.
+
+    """
+
+def get_tag_argument() -> Optional[str]:
+    """Return the value passed for the ``--tag`` argument, if any.
+
+    The ``--tag`` argument is not used directly by Alembic,
+    but is available for custom ``env.py`` configurations that
+    wish to use it; particularly for offline generation scripts
+    that wish to generate tagged filenames.
+
+    This function does not require that the :class:`.MigrationContext`
+    has been configured.
+
+    .. seealso::
+
+        :meth:`.EnvironmentContext.get_x_argument` - a newer and more
+        open ended system of extending ``env.py`` scripts via the command
+        line.
+
+    """
+
+@overload
+def get_x_argument(as_dictionary: Literal[False]) -> List[str]: ...
+@overload
+def get_x_argument(as_dictionary: Literal[True]) -> Dict[str, str]: ...
+@overload
+def get_x_argument(
+    as_dictionary: bool = ...,
+) -> Union[List[str], Dict[str, str]]:
+    """Return the value(s) passed for the ``-x`` argument, if any.
+
+    The ``-x`` argument is an open ended flag that allows any user-defined
+    value or values to be passed on the command line, then available
+    here for consumption by a custom ``env.py`` script.
+
+    The return value is a list, returned directly from the ``argparse``
+    structure.  If ``as_dictionary=True`` is passed, the ``x`` arguments
+    are parsed using ``key=value`` format into a dictionary that is
+    then returned. If there is no ``=`` in the argument, value is an empty
+    string.
+
+    .. versionchanged:: 1.13.1 Support ``as_dictionary=True`` when
+       arguments are passed without the ``=`` symbol.
+
+    For example, to support passing a database URL on the command line,
+    the standard ``env.py`` script can be modified like this::
+
+        cmd_line_url = context.get_x_argument(
+            as_dictionary=True).get('dbname')
+        if cmd_line_url:
+            engine = create_engine(cmd_line_url)
+        else:
+            engine = engine_from_config(
+                    config.get_section(config.config_ini_section),
+                    prefix='sqlalchemy.',
+                    poolclass=pool.NullPool)
+
+    This then takes effect by running the ``alembic`` script as::
+
+        alembic -x dbname=postgresql://user:pass@host/dbname upgrade head
+
+    This function does not require that the :class:`.MigrationContext`
+    has been configured.
+
+    .. seealso::
+
+        :meth:`.EnvironmentContext.get_tag_argument`
+
+        :attr:`.Config.cmd_opts`
+
+    """
+
+def is_offline_mode() -> bool:
+    """Return True if the current migrations environment
+    is running in "offline mode".
+
+    This is ``True`` or ``False`` depending
+    on the ``--sql`` flag passed.
+
+    This function does not require that the :class:`.MigrationContext`
+    has been configured.
+
+    """
+
+def is_transactional_ddl() -> bool:
+    """Return True if the context is configured to expect a
+    transactional DDL capable backend.
+
+    This defaults to the type of database in use, and
+    can be overridden by the ``transactional_ddl`` argument
+    to :meth:`.configure`
+
+    This function requires that a :class:`.MigrationContext`
+    has first been made available via :meth:`.configure`.
+
+    """
+
+def run_migrations(**kw: Any) -> None:
+    """Run migrations as determined by the current command line
+    configuration
+    as well as versioning information present (or not) in the current
+    database connection (if one is present).
+
+    The function accepts optional ``**kw`` arguments.   If these are
+    passed, they are sent directly to the ``upgrade()`` and
+    ``downgrade()``
+    functions within each target revision file.   By modifying the
+    ``script.py.mako`` file so that the ``upgrade()`` and ``downgrade()``
+    functions accept arguments, parameters can be passed here so that
+    contextual information, usually information to identify a particular
+    database in use, can be passed from a custom ``env.py`` script
+    to the migration functions.
+
+    This function requires that a :class:`.MigrationContext` has
+    first been made available via :meth:`.configure`.
+
+    """
+
+script: ScriptDirectory
+
+def static_output(text: str) -> None:
+    """Emit text directly to the "offline" SQL stream.
+
+    Typically this is for emitting comments that
+    start with --.  The statement is not treated
+    as a SQL execution, no ; or batch separator
+    is added, etc.
+
+    """

.venv2/Lib/site-packages/alembic/ddl/__init__.py

@@ -0,0 +1,6 @@
+from . import mssql
+from . import mysql
+from . import oracle
+from . import postgresql
+from . import sqlite
+from .impl import DefaultImpl as DefaultImpl

.venv2/Lib/site-packages/alembic/ddl/_autogen.py

@@ -0,0 +1,325 @@
+# mypy: allow-untyped-defs, allow-incomplete-defs, allow-untyped-calls
+# mypy: no-warn-return-any, allow-any-generics
+
+from __future__ import annotations
+
+from typing import Any
+from typing import ClassVar
+from typing import Dict
+from typing import Generic
+from typing import NamedTuple
+from typing import Optional
+from typing import Sequence
+from typing import Tuple
+from typing import Type
+from typing import TYPE_CHECKING
+from typing import TypeVar
+from typing import Union
+
+from sqlalchemy.sql.schema import Constraint
+from sqlalchemy.sql.schema import ForeignKeyConstraint
+from sqlalchemy.sql.schema import Index
+from sqlalchemy.sql.schema import UniqueConstraint
+from typing_extensions import TypeGuard
+
+from .. import util
+from ..util import sqla_compat
+
+if TYPE_CHECKING:
+    from typing import Literal
+
+    from alembic.autogenerate.api import AutogenContext
+    from alembic.ddl.impl import DefaultImpl
+
+CompareConstraintType = Union[Constraint, Index]
+
+_C = TypeVar("_C", bound=CompareConstraintType)
+
+_clsreg: Dict[str, Type[_constraint_sig]] = {}
+
+
+class ComparisonResult(NamedTuple):
+    status: Literal["equal", "different", "skip"]
+    message: str
+
+    @property
+    def is_equal(self) -> bool:
+        return self.status == "equal"
+
+    @property
+    def is_different(self) -> bool:
+        return self.status == "different"
+
+    @property
+    def is_skip(self) -> bool:
+        return self.status == "skip"
+
+    @classmethod
+    def Equal(cls) -> ComparisonResult:
+        """the constraints are equal."""
+        return cls("equal", "The two constraints are equal")
+
+    @classmethod
+    def Different(cls, reason: Union[str, Sequence[str]]) -> ComparisonResult:
+        """the constraints are different for the provided reason(s)."""
+        return cls("different", ", ".join(util.to_list(reason)))
+
+    @classmethod
+    def Skip(cls, reason: Union[str, Sequence[str]]) -> ComparisonResult:
+        """the constraint cannot be compared for the provided reason(s).
+
+        The message is logged, but the constraints will be otherwise
+        considered equal, meaning that no migration command will be
+        generated.
+        """
+        return cls("skip", ", ".join(util.to_list(reason)))
+
+
+class _constraint_sig(Generic[_C]):
+    const: _C
+
+    _sig: Tuple[Any, ...]
+    name: Optional[sqla_compat._ConstraintNameDefined]
+
+    impl: DefaultImpl
+
+    _is_index: ClassVar[bool] = False
+    _is_fk: ClassVar[bool] = False
+    _is_uq: ClassVar[bool] = False
+
+    _is_metadata: bool
+
+    def __init_subclass__(cls) -> None:
+        cls._register()
+
+    @classmethod
+    def _register(cls):
+        raise NotImplementedError()
+
+    def __init__(
+        self, is_metadata: bool, impl: DefaultImpl, const: _C
+    ) -> None:
+        raise NotImplementedError()
+
+    def compare_to_reflected(
+        self, other: _constraint_sig[Any]
+    ) -> ComparisonResult:
+        assert self.impl is other.impl
+        assert self._is_metadata
+        assert not other._is_metadata
+
+        return self._compare_to_reflected(other)
+
+    def _compare_to_reflected(
+        self, other: _constraint_sig[_C]
+    ) -> ComparisonResult:
+        raise NotImplementedError()
+
+    @classmethod
+    def from_constraint(
+        cls, is_metadata: bool, impl: DefaultImpl, constraint: _C
+    ) -> _constraint_sig[_C]:
+        # these could be cached by constraint/impl, however, if the
+        # constraint is modified in place, then the sig is wrong.  the mysql
+        # impl currently does this, and if we fixed that we can't be sure
+        # someone else might do it too, so play it safe.
+        sig = _clsreg[constraint.__visit_name__](is_metadata, impl, constraint)
+        return sig
+
+    def md_name_to_sql_name(self, context: AutogenContext) -> Optional[str]:
+        return sqla_compat._get_constraint_final_name(
+            self.const, context.dialect
+        )
+
+    @util.memoized_property
+    def is_named(self):
+        return sqla_compat._constraint_is_named(self.const, self.impl.dialect)
+
+    @util.memoized_property
+    def unnamed(self) -> Tuple[Any, ...]:
+        return self._sig
+
+    @util.memoized_property
+    def unnamed_no_options(self) -> Tuple[Any, ...]:
+        raise NotImplementedError()
+
+    @util.memoized_property
+    def _full_sig(self) -> Tuple[Any, ...]:
+        return (self.name,) + self.unnamed
+
+    def __eq__(self, other) -> bool:
+        return self._full_sig == other._full_sig
+
+    def __ne__(self, other) -> bool:
+        return self._full_sig != other._full_sig
+
+    def __hash__(self) -> int:
+        return hash(self._full_sig)
+
+
+class _uq_constraint_sig(_constraint_sig[UniqueConstraint]):
+    _is_uq = True
+
+    @classmethod
+    def _register(cls) -> None:
+        _clsreg["unique_constraint"] = cls
+
+    is_unique = True
+
+    def __init__(
+        self,
+        is_metadata: bool,
+        impl: DefaultImpl,
+        const: UniqueConstraint,
+    ) -> None:
+        self.impl = impl
+        self.const = const
+        self.name = sqla_compat.constraint_name_or_none(const.name)
+        self._sig = tuple(sorted([col.name for col in const.columns]))
+        self._is_metadata = is_metadata
+
+    @property
+    def column_names(self) -> Tuple[str, ...]:
+        return tuple([col.name for col in self.const.columns])
+
+    def _compare_to_reflected(
+        self, other: _constraint_sig[_C]
+    ) -> ComparisonResult:
+        assert self._is_metadata
+        metadata_obj = self
+        conn_obj = other
+
+        assert is_uq_sig(conn_obj)
+        return self.impl.compare_unique_constraint(
+            metadata_obj.const, conn_obj.const
+        )
+
+
+class _ix_constraint_sig(_constraint_sig[Index]):
+    _is_index = True
+
+    name: sqla_compat._ConstraintName
+
+    @classmethod
+    def _register(cls) -> None:
+        _clsreg["index"] = cls
+
+    def __init__(
+        self, is_metadata: bool, impl: DefaultImpl, const: Index
+    ) -> None:
+        self.impl = impl
+        self.const = const
+        self.name = const.name
+        self.is_unique = bool(const.unique)
+        self._is_metadata = is_metadata
+
+    def _compare_to_reflected(
+        self, other: _constraint_sig[_C]
+    ) -> ComparisonResult:
+        assert self._is_metadata
+        metadata_obj = self
+        conn_obj = other
+
+        assert is_index_sig(conn_obj)
+        return self.impl.compare_indexes(metadata_obj.const, conn_obj.const)
+
+    @util.memoized_property
+    def has_expressions(self):
+        return sqla_compat.is_expression_index(self.const)
+
+    @util.memoized_property
+    def column_names(self) -> Tuple[str, ...]:
+        return tuple([col.name for col in self.const.columns])
+
+    @util.memoized_property
+    def column_names_optional(self) -> Tuple[Optional[str], ...]:
+        return tuple(
+            [getattr(col, "name", None) for col in self.const.expressions]
+        )
+
+    @util.memoized_property
+    def is_named(self):
+        return True
+
+    @util.memoized_property
+    def unnamed(self):
+        return (self.is_unique,) + self.column_names_optional
+
+
+class _fk_constraint_sig(_constraint_sig[ForeignKeyConstraint]):
+    _is_fk = True
+
+    @classmethod
+    def _register(cls) -> None:
+        _clsreg["foreign_key_constraint"] = cls
+
+    def __init__(
+        self,
+        is_metadata: bool,
+        impl: DefaultImpl,
+        const: ForeignKeyConstraint,
+    ) -> None:
+        self._is_metadata = is_metadata
+
+        self.impl = impl
+        self.const = const
+
+        self.name = sqla_compat.constraint_name_or_none(const.name)
+
+        (
+            self.source_schema,
+            self.source_table,
+            self.source_columns,
+            self.target_schema,
+            self.target_table,
+            self.target_columns,
+            onupdate,
+            ondelete,
+            deferrable,
+            initially,
+        ) = sqla_compat._fk_spec(const)
+
+        self._sig: Tuple[Any, ...] = (
+            self.source_schema,
+            self.source_table,
+            tuple(self.source_columns),
+            self.target_schema,
+            self.target_table,
+            tuple(self.target_columns),
+        ) + (
+            (None if onupdate.lower() == "no action" else onupdate.lower())
+            if onupdate
+            else None,
+            (None if ondelete.lower() == "no action" else ondelete.lower())
+            if ondelete
+            else None,
+            # convert initially + deferrable into one three-state value
+            "initially_deferrable"
+            if initially and initially.lower() == "deferred"
+            else "deferrable"
+            if deferrable
+            else "not deferrable",
+        )
+
+    @util.memoized_property
+    def unnamed_no_options(self):
+        return (
+            self.source_schema,
+            self.source_table,
+            tuple(self.source_columns),
+            self.target_schema,
+            self.target_table,
+            tuple(self.target_columns),
+        )
+
+
+def is_index_sig(sig: _constraint_sig) -> TypeGuard[_ix_constraint_sig]:
+    return sig._is_index
+
+
+def is_uq_sig(sig: _constraint_sig) -> TypeGuard[_uq_constraint_sig]:
+    return sig._is_uq
+
+
+def is_fk_sig(sig: _constraint_sig) -> TypeGuard[_fk_constraint_sig]:
+    return sig._is_fk

.venv2/Lib/site-packages/alembic/ddl/base.py

@@ -0,0 +1,335 @@
+# mypy: allow-untyped-defs, allow-incomplete-defs, allow-untyped-calls
+# mypy: no-warn-return-any, allow-any-generics
+
+from __future__ import annotations
+
+import functools
+from typing import Optional
+from typing import TYPE_CHECKING
+from typing import Union
+
+from sqlalchemy import exc
+from sqlalchemy import Integer
+from sqlalchemy import types as sqltypes
+from sqlalchemy.ext.compiler import compiles
+from sqlalchemy.schema import Column
+from sqlalchemy.schema import DDLElement
+from sqlalchemy.sql.elements import quoted_name
+
+from ..util.sqla_compat import _columns_for_constraint  # noqa
+from ..util.sqla_compat import _find_columns  # noqa
+from ..util.sqla_compat import _fk_spec  # noqa
+from ..util.sqla_compat import _is_type_bound  # noqa
+from ..util.sqla_compat import _table_for_constraint  # noqa
+
+if TYPE_CHECKING:
+    from typing import Any
+
+    from sqlalchemy.sql.compiler import Compiled
+    from sqlalchemy.sql.compiler import DDLCompiler
+    from sqlalchemy.sql.elements import TextClause
+    from sqlalchemy.sql.functions import Function
+    from sqlalchemy.sql.schema import FetchedValue
+    from sqlalchemy.sql.type_api import TypeEngine
+
+    from .impl import DefaultImpl
+    from ..util.sqla_compat import Computed
+    from ..util.sqla_compat import Identity
+
+_ServerDefault = Union["TextClause", "FetchedValue", "Function[Any]", str]
+
+
+class AlterTable(DDLElement):
+
+    """Represent an ALTER TABLE statement.
+
+    Only the string name and optional schema name of the table
+    is required, not a full Table object.
+
+    """
+
+    def __init__(
+        self,
+        table_name: str,
+        schema: Optional[Union[quoted_name, str]] = None,
+    ) -> None:
+        self.table_name = table_name
+        self.schema = schema
+
+
+class RenameTable(AlterTable):
+    def __init__(
+        self,
+        old_table_name: str,
+        new_table_name: Union[quoted_name, str],
+        schema: Optional[Union[quoted_name, str]] = None,
+    ) -> None:
+        super().__init__(old_table_name, schema=schema)
+        self.new_table_name = new_table_name
+
+
+class AlterColumn(AlterTable):
+    def __init__(
+        self,
+        name: str,
+        column_name: str,
+        schema: Optional[str] = None,
+        existing_type: Optional[TypeEngine] = None,
+        existing_nullable: Optional[bool] = None,
+        existing_server_default: Optional[_ServerDefault] = None,
+        existing_comment: Optional[str] = None,
+    ) -> None:
+        super().__init__(name, schema=schema)
+        self.column_name = column_name
+        self.existing_type = (
+            sqltypes.to_instance(existing_type)
+            if existing_type is not None
+            else None
+        )
+        self.existing_nullable = existing_nullable
+        self.existing_server_default = existing_server_default
+        self.existing_comment = existing_comment
+
+
+class ColumnNullable(AlterColumn):
+    def __init__(
+        self, name: str, column_name: str, nullable: bool, **kw
+    ) -> None:
+        super().__init__(name, column_name, **kw)
+        self.nullable = nullable
+
+
+class ColumnType(AlterColumn):
+    def __init__(
+        self, name: str, column_name: str, type_: TypeEngine, **kw
+    ) -> None:
+        super().__init__(name, column_name, **kw)
+        self.type_ = sqltypes.to_instance(type_)
+
+
+class ColumnName(AlterColumn):
+    def __init__(
+        self, name: str, column_name: str, newname: str, **kw
+    ) -> None:
+        super().__init__(name, column_name, **kw)
+        self.newname = newname
+
+
+class ColumnDefault(AlterColumn):
+    def __init__(
+        self,
+        name: str,
+        column_name: str,
+        default: Optional[_ServerDefault],
+        **kw,
+    ) -> None:
+        super().__init__(name, column_name, **kw)
+        self.default = default
+
+
+class ComputedColumnDefault(AlterColumn):
+    def __init__(
+        self, name: str, column_name: str, default: Optional[Computed], **kw
+    ) -> None:
+        super().__init__(name, column_name, **kw)
+        self.default = default
+
+
+class IdentityColumnDefault(AlterColumn):
+    def __init__(
+        self,
+        name: str,
+        column_name: str,
+        default: Optional[Identity],
+        impl: DefaultImpl,
+        **kw,
+    ) -> None:
+        super().__init__(name, column_name, **kw)
+        self.default = default
+        self.impl = impl
+
+
+class AddColumn(AlterTable):
+    def __init__(
+        self,
+        name: str,
+        column: Column[Any],
+        schema: Optional[Union[quoted_name, str]] = None,
+    ) -> None:
+        super().__init__(name, schema=schema)
+        self.column = column
+
+
+class DropColumn(AlterTable):
+    def __init__(
+        self, name: str, column: Column[Any], schema: Optional[str] = None
+    ) -> None:
+        super().__init__(name, schema=schema)
+        self.column = column
+
+
+class ColumnComment(AlterColumn):
+    def __init__(
+        self, name: str, column_name: str, comment: Optional[str], **kw
+    ) -> None:
+        super().__init__(name, column_name, **kw)
+        self.comment = comment
+
+
+@compiles(RenameTable)  # type: ignore[misc]
+def visit_rename_table(
+    element: RenameTable, compiler: DDLCompiler, **kw
+) -> str:
+    return "%s RENAME TO %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        format_table_name(compiler, element.new_table_name, element.schema),
+    )
+
+
+@compiles(AddColumn)  # type: ignore[misc]
+def visit_add_column(element: AddColumn, compiler: DDLCompiler, **kw) -> str:
+    return "%s %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        add_column(compiler, element.column, **kw),
+    )
+
+
+@compiles(DropColumn)  # type: ignore[misc]
+def visit_drop_column(element: DropColumn, compiler: DDLCompiler, **kw) -> str:
+    return "%s %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        drop_column(compiler, element.column.name, **kw),
+    )
+
+
+@compiles(ColumnNullable)  # type: ignore[misc]
+def visit_column_nullable(
+    element: ColumnNullable, compiler: DDLCompiler, **kw
+) -> str:
+    return "%s %s %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        alter_column(compiler, element.column_name),
+        "DROP NOT NULL" if element.nullable else "SET NOT NULL",
+    )
+
+
+@compiles(ColumnType)  # type: ignore[misc]
+def visit_column_type(element: ColumnType, compiler: DDLCompiler, **kw) -> str:
+    return "%s %s %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        alter_column(compiler, element.column_name),
+        "TYPE %s" % format_type(compiler, element.type_),
+    )
+
+
+@compiles(ColumnName)  # type: ignore[misc]
+def visit_column_name(element: ColumnName, compiler: DDLCompiler, **kw) -> str:
+    return "%s RENAME %s TO %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        format_column_name(compiler, element.column_name),
+        format_column_name(compiler, element.newname),
+    )
+
+
+@compiles(ColumnDefault)  # type: ignore[misc]
+def visit_column_default(
+    element: ColumnDefault, compiler: DDLCompiler, **kw
+) -> str:
+    return "%s %s %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        alter_column(compiler, element.column_name),
+        "SET DEFAULT %s" % format_server_default(compiler, element.default)
+        if element.default is not None
+        else "DROP DEFAULT",
+    )
+
+
+@compiles(ComputedColumnDefault)  # type: ignore[misc]
+def visit_computed_column(
+    element: ComputedColumnDefault, compiler: DDLCompiler, **kw
+):
+    raise exc.CompileError(
+        'Adding or removing a "computed" construct, e.g. GENERATED '
+        "ALWAYS AS, to or from an existing column is not supported."
+    )
+
+
+@compiles(IdentityColumnDefault)  # type: ignore[misc]
+def visit_identity_column(
+    element: IdentityColumnDefault, compiler: DDLCompiler, **kw
+):
+    raise exc.CompileError(
+        'Adding, removing or modifying an "identity" construct, '
+        "e.g. GENERATED AS IDENTITY, to or from an existing "
+        "column is not supported in this dialect."
+    )
+
+
+def quote_dotted(
+    name: Union[quoted_name, str], quote: functools.partial
+) -> Union[quoted_name, str]:
+    """quote the elements of a dotted name"""
+
+    if isinstance(name, quoted_name):
+        return quote(name)
+    result = ".".join([quote(x) for x in name.split(".")])
+    return result
+
+
+def format_table_name(
+    compiler: Compiled,
+    name: Union[quoted_name, str],
+    schema: Optional[Union[quoted_name, str]],
+) -> Union[quoted_name, str]:
+    quote = functools.partial(compiler.preparer.quote)
+    if schema:
+        return quote_dotted(schema, quote) + "." + quote(name)
+    else:
+        return quote(name)
+
+
+def format_column_name(
+    compiler: DDLCompiler, name: Optional[Union[quoted_name, str]]
+) -> Union[quoted_name, str]:
+    return compiler.preparer.quote(name)  # type: ignore[arg-type]
+
+
+def format_server_default(
+    compiler: DDLCompiler,
+    default: Optional[_ServerDefault],
+) -> str:
+    return compiler.get_column_default_string(
+        Column("x", Integer, server_default=default)
+    )
+
+
+def format_type(compiler: DDLCompiler, type_: TypeEngine) -> str:
+    return compiler.dialect.type_compiler.process(type_)
+
+
+def alter_table(
+    compiler: DDLCompiler,
+    name: str,
+    schema: Optional[str],
+) -> str:
+    return "ALTER TABLE %s" % format_table_name(compiler, name, schema)
+
+
+def drop_column(compiler: DDLCompiler, name: str, **kw) -> str:
+    return "DROP COLUMN %s" % format_column_name(compiler, name)
+
+
+def alter_column(compiler: DDLCompiler, name: str) -> str:
+    return "ALTER COLUMN %s" % format_column_name(compiler, name)
+
+
+def add_column(compiler: DDLCompiler, column: Column[Any], **kw) -> str:
+    text = "ADD COLUMN %s" % compiler.get_column_specification(column, **kw)
+
+    const = " ".join(
+        compiler.process(constraint) for constraint in column.constraints
+    )
+    if const:
+        text += " " + const
+
+    return text

.venv2/Lib/site-packages/alembic/ddl/impl.py

@@ -0,0 +1,844 @@
+# mypy: allow-untyped-defs, allow-incomplete-defs, allow-untyped-calls
+# mypy: no-warn-return-any, allow-any-generics
+
+from __future__ import annotations
+
+import logging
+import re
+from typing import Any
+from typing import Callable
+from typing import Dict
+from typing import Iterable
+from typing import List
+from typing import Mapping
+from typing import NamedTuple
+from typing import Optional
+from typing import Sequence
+from typing import Set
+from typing import Tuple
+from typing import Type
+from typing import TYPE_CHECKING
+from typing import Union
+
+from sqlalchemy import cast
+from sqlalchemy import schema
+from sqlalchemy import text
+
+from . import _autogen
+from . import base
+from ._autogen import _constraint_sig as _constraint_sig
+from ._autogen import ComparisonResult as ComparisonResult
+from .. import util
+from ..util import sqla_compat
+
+if TYPE_CHECKING:
+    from typing import Literal
+    from typing import TextIO
+
+    from sqlalchemy.engine import Connection
+    from sqlalchemy.engine import Dialect
+    from sqlalchemy.engine.cursor import CursorResult
+    from sqlalchemy.engine.reflection import Inspector
+    from sqlalchemy.sql import ClauseElement
+    from sqlalchemy.sql import Executable
+    from sqlalchemy.sql.elements import ColumnElement
+    from sqlalchemy.sql.elements import quoted_name
+    from sqlalchemy.sql.schema import Column
+    from sqlalchemy.sql.schema import Constraint
+    from sqlalchemy.sql.schema import ForeignKeyConstraint
+    from sqlalchemy.sql.schema import Index
+    from sqlalchemy.sql.schema import Table
+    from sqlalchemy.sql.schema import UniqueConstraint
+    from sqlalchemy.sql.selectable import TableClause
+    from sqlalchemy.sql.type_api import TypeEngine
+
+    from .base import _ServerDefault
+    from ..autogenerate.api import AutogenContext
+    from ..operations.batch import ApplyBatchImpl
+    from ..operations.batch import BatchOperationsImpl
+
+log = logging.getLogger(__name__)
+
+
+class ImplMeta(type):
+    def __init__(
+        cls,
+        classname: str,
+        bases: Tuple[Type[DefaultImpl]],
+        dict_: Dict[str, Any],
+    ):
+        newtype = type.__init__(cls, classname, bases, dict_)
+        if "__dialect__" in dict_:
+            _impls[dict_["__dialect__"]] = cls  # type: ignore[assignment]
+        return newtype
+
+
+_impls: Dict[str, Type[DefaultImpl]] = {}
+
+
+class DefaultImpl(metaclass=ImplMeta):
+
+    """Provide the entrypoint for major migration operations,
+    including database-specific behavioral variances.
+
+    While individual SQL/DDL constructs already provide
+    for database-specific implementations, variances here
+    allow for entirely different sequences of operations
+    to take place for a particular migration, such as
+    SQL Server's special 'IDENTITY INSERT' step for
+    bulk inserts.
+
+    """
+
+    __dialect__ = "default"
+
+    transactional_ddl = False
+    command_terminator = ";"
+    type_synonyms: Tuple[Set[str], ...] = ({"NUMERIC", "DECIMAL"},)
+    type_arg_extract: Sequence[str] = ()
+    # These attributes are deprecated in SQLAlchemy via #10247. They need to
+    # be ignored to support older version that did not use dialect kwargs.
+    # They only apply to Oracle and are replaced by oracle_order,
+    # oracle_on_null
+    identity_attrs_ignore: Tuple[str, ...] = ("order", "on_null")
+
+    def __init__(
+        self,
+        dialect: Dialect,
+        connection: Optional[Connection],
+        as_sql: bool,
+        transactional_ddl: Optional[bool],
+        output_buffer: Optional[TextIO],
+        context_opts: Dict[str, Any],
+    ) -> None:
+        self.dialect = dialect
+        self.connection = connection
+        self.as_sql = as_sql
+        self.literal_binds = context_opts.get("literal_binds", False)
+
+        self.output_buffer = output_buffer
+        self.memo: dict = {}
+        self.context_opts = context_opts
+        if transactional_ddl is not None:
+            self.transactional_ddl = transactional_ddl
+
+        if self.literal_binds:
+            if not self.as_sql:
+                raise util.CommandError(
+                    "Can't use literal_binds setting without as_sql mode"
+                )
+
+    @classmethod
+    def get_by_dialect(cls, dialect: Dialect) -> Type[DefaultImpl]:
+        return _impls[dialect.name]
+
+    def static_output(self, text: str) -> None:
+        assert self.output_buffer is not None
+        self.output_buffer.write(text + "\n\n")
+        self.output_buffer.flush()
+
+    def requires_recreate_in_batch(
+        self, batch_op: BatchOperationsImpl
+    ) -> bool:
+        """Return True if the given :class:`.BatchOperationsImpl`
+        would need the table to be recreated and copied in order to
+        proceed.
+
+        Normally, only returns True on SQLite when operations other
+        than add_column are present.
+
+        """
+        return False
+
+    def prep_table_for_batch(
+        self, batch_impl: ApplyBatchImpl, table: Table
+    ) -> None:
+        """perform any operations needed on a table before a new
+        one is created to replace it in batch mode.
+
+        the PG dialect uses this to drop constraints on the table
+        before the new one uses those same names.
+
+        """
+
+    @property
+    def bind(self) -> Optional[Connection]:
+        return self.connection
+
+    def _exec(
+        self,
+        construct: Union[Executable, str],
+        execution_options: Optional[dict[str, Any]] = None,
+        multiparams: Sequence[dict] = (),
+        params: Dict[str, Any] = util.immutabledict(),
+    ) -> Optional[CursorResult]:
+        if isinstance(construct, str):
+            construct = text(construct)
+        if self.as_sql:
+            if multiparams or params:
+                # TODO: coverage
+                raise Exception("Execution arguments not allowed with as_sql")
+
+            compile_kw: dict[str, Any]
+            if self.literal_binds and not isinstance(
+                construct, schema.DDLElement
+            ):
+                compile_kw = dict(compile_kwargs={"literal_binds": True})
+            else:
+                compile_kw = {}
+
+            if TYPE_CHECKING:
+                assert isinstance(construct, ClauseElement)
+            compiled = construct.compile(dialect=self.dialect, **compile_kw)
+            self.static_output(
+                str(compiled).replace("\t", "    ").strip()
+                + self.command_terminator
+            )
+            return None
+        else:
+            conn = self.connection
+            assert conn is not None
+            if execution_options:
+                conn = conn.execution_options(**execution_options)
+            if params:
+                assert isinstance(multiparams, tuple)
+                multiparams += (params,)
+
+            return conn.execute(construct, multiparams)
+
+    def execute(
+        self,
+        sql: Union[Executable, str],
+        execution_options: Optional[dict[str, Any]] = None,
+    ) -> None:
+        self._exec(sql, execution_options)
+
+    def alter_column(
+        self,
+        table_name: str,
+        column_name: str,
+        nullable: Optional[bool] = None,
+        server_default: Union[_ServerDefault, Literal[False]] = False,
+        name: Optional[str] = None,
+        type_: Optional[TypeEngine] = None,
+        schema: Optional[str] = None,
+        autoincrement: Optional[bool] = None,
+        comment: Optional[Union[str, Literal[False]]] = False,
+        existing_comment: Optional[str] = None,
+        existing_type: Optional[TypeEngine] = None,
+        existing_server_default: Optional[_ServerDefault] = None,
+        existing_nullable: Optional[bool] = None,
+        existing_autoincrement: Optional[bool] = None,
+        **kw: Any,
+    ) -> None:
+        if autoincrement is not None or existing_autoincrement is not None:
+            util.warn(
+                "autoincrement and existing_autoincrement "
+                "only make sense for MySQL",
+                stacklevel=3,
+            )
+        if nullable is not None:
+            self._exec(
+                base.ColumnNullable(
+                    table_name,
+                    column_name,
+                    nullable,
+                    schema=schema,
+                    existing_type=existing_type,
+                    existing_server_default=existing_server_default,
+                    existing_nullable=existing_nullable,
+                    existing_comment=existing_comment,
+                )
+            )
+        if server_default is not False:
+            kw = {}
+            cls_: Type[
+                Union[
+                    base.ComputedColumnDefault,
+                    base.IdentityColumnDefault,
+                    base.ColumnDefault,
+                ]
+            ]
+            if sqla_compat._server_default_is_computed(
+                server_default, existing_server_default
+            ):
+                cls_ = base.ComputedColumnDefault
+            elif sqla_compat._server_default_is_identity(
+                server_default, existing_server_default
+            ):
+                cls_ = base.IdentityColumnDefault
+                kw["impl"] = self
+            else:
+                cls_ = base.ColumnDefault
+            self._exec(
+                cls_(
+                    table_name,
+                    column_name,
+                    server_default,  # type:ignore[arg-type]
+                    schema=schema,
+                    existing_type=existing_type,
+                    existing_server_default=existing_server_default,
+                    existing_nullable=existing_nullable,
+                    existing_comment=existing_comment,
+                    **kw,
+                )
+            )
+        if type_ is not None:
+            self._exec(
+                base.ColumnType(
+                    table_name,
+                    column_name,
+                    type_,
+                    schema=schema,
+                    existing_type=existing_type,
+                    existing_server_default=existing_server_default,
+                    existing_nullable=existing_nullable,
+                    existing_comment=existing_comment,
+                )
+            )
+
+        if comment is not False:
+            self._exec(
+                base.ColumnComment(
+                    table_name,
+                    column_name,
+                    comment,
+                    schema=schema,
+                    existing_type=existing_type,
+                    existing_server_default=existing_server_default,
+                    existing_nullable=existing_nullable,
+                    existing_comment=existing_comment,
+                )
+            )
+
+        # do the new name last ;)
+        if name is not None:
+            self._exec(
+                base.ColumnName(
+                    table_name,
+                    column_name,
+                    name,
+                    schema=schema,
+                    existing_type=existing_type,
+                    existing_server_default=existing_server_default,
+                    existing_nullable=existing_nullable,
+                )
+            )
+
+    def add_column(
+        self,
+        table_name: str,
+        column: Column[Any],
+        schema: Optional[Union[str, quoted_name]] = None,
+    ) -> None:
+        self._exec(base.AddColumn(table_name, column, schema=schema))
+
+    def drop_column(
+        self,
+        table_name: str,
+        column: Column[Any],
+        schema: Optional[str] = None,
+        **kw,
+    ) -> None:
+        self._exec(base.DropColumn(table_name, column, schema=schema))
+
+    def add_constraint(self, const: Any) -> None:
+        if const._create_rule is None or const._create_rule(self):
+            self._exec(schema.AddConstraint(const))
+
+    def drop_constraint(self, const: Constraint) -> None:
+        self._exec(schema.DropConstraint(const))
+
+    def rename_table(
+        self,
+        old_table_name: str,
+        new_table_name: Union[str, quoted_name],
+        schema: Optional[Union[str, quoted_name]] = None,
+    ) -> None:
+        self._exec(
+            base.RenameTable(old_table_name, new_table_name, schema=schema)
+        )
+
+    def create_table(self, table: Table) -> None:
+        table.dispatch.before_create(
+            table, self.connection, checkfirst=False, _ddl_runner=self
+        )
+        self._exec(schema.CreateTable(table))
+        table.dispatch.after_create(
+            table, self.connection, checkfirst=False, _ddl_runner=self
+        )
+        for index in table.indexes:
+            self._exec(schema.CreateIndex(index))
+
+        with_comment = (
+            self.dialect.supports_comments and not self.dialect.inline_comments
+        )
+        comment = table.comment
+        if comment and with_comment:
+            self.create_table_comment(table)
+
+        for column in table.columns:
+            comment = column.comment
+            if comment and with_comment:
+                self.create_column_comment(column)
+
+    def drop_table(self, table: Table) -> None:
+        table.dispatch.before_drop(
+            table, self.connection, checkfirst=False, _ddl_runner=self
+        )
+        self._exec(schema.DropTable(table))
+        table.dispatch.after_drop(
+            table, self.connection, checkfirst=False, _ddl_runner=self
+        )
+
+    def create_index(self, index: Index, **kw: Any) -> None:
+        self._exec(schema.CreateIndex(index, **kw))
+
+    def create_table_comment(self, table: Table) -> None:
+        self._exec(schema.SetTableComment(table))
+
+    def drop_table_comment(self, table: Table) -> None:
+        self._exec(schema.DropTableComment(table))
+
+    def create_column_comment(self, column: ColumnElement[Any]) -> None:
+        self._exec(schema.SetColumnComment(column))
+
+    def drop_index(self, index: Index, **kw: Any) -> None:
+        self._exec(schema.DropIndex(index, **kw))
+
+    def bulk_insert(
+        self,
+        table: Union[TableClause, Table],
+        rows: List[dict],
+        multiinsert: bool = True,
+    ) -> None:
+        if not isinstance(rows, list):
+            raise TypeError("List expected")
+        elif rows and not isinstance(rows[0], dict):
+            raise TypeError("List of dictionaries expected")
+        if self.as_sql:
+            for row in rows:
+                self._exec(
+                    sqla_compat._insert_inline(table).values(
+                        **{
+                            k: sqla_compat._literal_bindparam(
+                                k, v, type_=table.c[k].type
+                            )
+                            if not isinstance(
+                                v, sqla_compat._literal_bindparam
+                            )
+                            else v
+                            for k, v in row.items()
+                        }
+                    )
+                )
+        else:
+            if rows:
+                if multiinsert:
+                    self._exec(
+                        sqla_compat._insert_inline(table), multiparams=rows
+                    )
+                else:
+                    for row in rows:
+                        self._exec(
+                            sqla_compat._insert_inline(table).values(**row)
+                        )
+
+    def _tokenize_column_type(self, column: Column) -> Params:
+        definition: str
+        definition = self.dialect.type_compiler.process(column.type).lower()
+
+        # tokenize the SQLAlchemy-generated version of a type, so that
+        # the two can be compared.
+        #
+        # examples:
+        # NUMERIC(10, 5)
+        # TIMESTAMP WITH TIMEZONE
+        # INTEGER UNSIGNED
+        # INTEGER (10) UNSIGNED
+        # INTEGER(10) UNSIGNED
+        # varchar character set utf8
+        #
+
+        tokens: List[str] = re.findall(r"[\w\-_]+|\(.+?\)", definition)
+
+        term_tokens: List[str] = []
+        paren_term = None
+
+        for token in tokens:
+            if re.match(r"^\(.*\)$", token):
+                paren_term = token
+            else:
+                term_tokens.append(token)
+
+        params = Params(term_tokens[0], term_tokens[1:], [], {})
+
+        if paren_term:
+            term: str
+            for term in re.findall("[^(),]+", paren_term):
+                if "=" in term:
+                    key, val = term.split("=")
+                    params.kwargs[key.strip()] = val.strip()
+                else:
+                    params.args.append(term.strip())
+
+        return params
+
+    def _column_types_match(
+        self, inspector_params: Params, metadata_params: Params
+    ) -> bool:
+        if inspector_params.token0 == metadata_params.token0:
+            return True
+
+        synonyms = [{t.lower() for t in batch} for batch in self.type_synonyms]
+        inspector_all_terms = " ".join(
+            [inspector_params.token0] + inspector_params.tokens
+        )
+        metadata_all_terms = " ".join(
+            [metadata_params.token0] + metadata_params.tokens
+        )
+
+        for batch in synonyms:
+            if {inspector_all_terms, metadata_all_terms}.issubset(batch) or {
+                inspector_params.token0,
+                metadata_params.token0,
+            }.issubset(batch):
+                return True
+        return False
+
+    def _column_args_match(
+        self, inspected_params: Params, meta_params: Params
+    ) -> bool:
+        """We want to compare column parameters. However, we only want
+        to compare parameters that are set. If they both have `collation`,
+        we want to make sure they are the same. However, if only one
+        specifies it, dont flag it for being less specific
+        """
+
+        if (
+            len(meta_params.tokens) == len(inspected_params.tokens)
+            and meta_params.tokens != inspected_params.tokens
+        ):
+            return False
+
+        if (
+            len(meta_params.args) == len(inspected_params.args)
+            and meta_params.args != inspected_params.args
+        ):
+            return False
+
+        insp = " ".join(inspected_params.tokens).lower()
+        meta = " ".join(meta_params.tokens).lower()
+
+        for reg in self.type_arg_extract:
+            mi = re.search(reg, insp)
+            mm = re.search(reg, meta)
+
+            if mi and mm and mi.group(1) != mm.group(1):
+                return False
+
+        return True
+
+    def compare_type(
+        self, inspector_column: Column[Any], metadata_column: Column
+    ) -> bool:
+        """Returns True if there ARE differences between the types of the two
+        columns. Takes impl.type_synonyms into account between retrospected
+        and metadata types
+        """
+        inspector_params = self._tokenize_column_type(inspector_column)
+        metadata_params = self._tokenize_column_type(metadata_column)
+
+        if not self._column_types_match(inspector_params, metadata_params):
+            return True
+        if not self._column_args_match(inspector_params, metadata_params):
+            return True
+        return False
+
+    def compare_server_default(
+        self,
+        inspector_column,
+        metadata_column,
+        rendered_metadata_default,
+        rendered_inspector_default,
+    ):
+        return rendered_inspector_default != rendered_metadata_default
+
+    def correct_for_autogen_constraints(
+        self,
+        conn_uniques: Set[UniqueConstraint],
+        conn_indexes: Set[Index],
+        metadata_unique_constraints: Set[UniqueConstraint],
+        metadata_indexes: Set[Index],
+    ) -> None:
+        pass
+
+    def cast_for_batch_migrate(self, existing, existing_transfer, new_type):
+        if existing.type._type_affinity is not new_type._type_affinity:
+            existing_transfer["expr"] = cast(
+                existing_transfer["expr"], new_type
+            )
+
+    def render_ddl_sql_expr(
+        self, expr: ClauseElement, is_server_default: bool = False, **kw: Any
+    ) -> str:
+        """Render a SQL expression that is typically a server default,
+        index expression, etc.
+
+        """
+
+        compile_kw = {"literal_binds": True, "include_table": False}
+
+        return str(
+            expr.compile(dialect=self.dialect, compile_kwargs=compile_kw)
+        )
+
+    def _compat_autogen_column_reflect(self, inspector: Inspector) -> Callable:
+        return self.autogen_column_reflect
+
+    def correct_for_autogen_foreignkeys(
+        self,
+        conn_fks: Set[ForeignKeyConstraint],
+        metadata_fks: Set[ForeignKeyConstraint],
+    ) -> None:
+        pass
+
+    def autogen_column_reflect(self, inspector, table, column_info):
+        """A hook that is attached to the 'column_reflect' event for when
+        a Table is reflected from the database during the autogenerate
+        process.
+
+        Dialects can elect to modify the information gathered here.
+
+        """
+
+    def start_migrations(self) -> None:
+        """A hook called when :meth:`.EnvironmentContext.run_migrations`
+        is called.
+
+        Implementations can set up per-migration-run state here.
+
+        """
+
+    def emit_begin(self) -> None:
+        """Emit the string ``BEGIN``, or the backend-specific
+        equivalent, on the current connection context.
+
+        This is used in offline mode and typically
+        via :meth:`.EnvironmentContext.begin_transaction`.
+
+        """
+        self.static_output("BEGIN" + self.command_terminator)
+
+    def emit_commit(self) -> None:
+        """Emit the string ``COMMIT``, or the backend-specific
+        equivalent, on the current connection context.
+
+        This is used in offline mode and typically
+        via :meth:`.EnvironmentContext.begin_transaction`.
+
+        """
+        self.static_output("COMMIT" + self.command_terminator)
+
+    def render_type(
+        self, type_obj: TypeEngine, autogen_context: AutogenContext
+    ) -> Union[str, Literal[False]]:
+        return False
+
+    def _compare_identity_default(self, metadata_identity, inspector_identity):
+        # ignored contains the attributes that were not considered
+        # because assumed to their default values in the db.
+        diff, ignored = _compare_identity_options(
+            metadata_identity,
+            inspector_identity,
+            sqla_compat.Identity(),
+            skip={"always"},
+        )
+
+        meta_always = getattr(metadata_identity, "always", None)
+        inspector_always = getattr(inspector_identity, "always", None)
+        # None and False are the same in this comparison
+        if bool(meta_always) != bool(inspector_always):
+            diff.add("always")
+
+        diff.difference_update(self.identity_attrs_ignore)
+
+        # returns 3 values:
+        return (
+            # different identity attributes
+            diff,
+            # ignored identity attributes
+            ignored,
+            # if the two identity should be considered different
+            bool(diff) or bool(metadata_identity) != bool(inspector_identity),
+        )
+
+    def _compare_index_unique(
+        self, metadata_index: Index, reflected_index: Index
+    ) -> Optional[str]:
+        conn_unique = bool(reflected_index.unique)
+        meta_unique = bool(metadata_index.unique)
+        if conn_unique != meta_unique:
+            return f"unique={conn_unique} to unique={meta_unique}"
+        else:
+            return None
+
+    def _create_metadata_constraint_sig(
+        self, constraint: _autogen._C, **opts: Any
+    ) -> _constraint_sig[_autogen._C]:
+        return _constraint_sig.from_constraint(True, self, constraint, **opts)
+
+    def _create_reflected_constraint_sig(
+        self, constraint: _autogen._C, **opts: Any
+    ) -> _constraint_sig[_autogen._C]:
+        return _constraint_sig.from_constraint(False, self, constraint, **opts)
+
+    def compare_indexes(
+        self,
+        metadata_index: Index,
+        reflected_index: Index,
+    ) -> ComparisonResult:
+        """Compare two indexes by comparing the signature generated by
+        ``create_index_sig``.
+
+        This method returns a ``ComparisonResult``.
+        """
+        msg: List[str] = []
+        unique_msg = self._compare_index_unique(
+            metadata_index, reflected_index
+        )
+        if unique_msg:
+            msg.append(unique_msg)
+        m_sig = self._create_metadata_constraint_sig(metadata_index)
+        r_sig = self._create_reflected_constraint_sig(reflected_index)
+
+        assert _autogen.is_index_sig(m_sig)
+        assert _autogen.is_index_sig(r_sig)
+
+        # The assumption is that the index have no expression
+        for sig in m_sig, r_sig:
+            if sig.has_expressions:
+                log.warning(
+                    "Generating approximate signature for index %s. "
+                    "The dialect "
+                    "implementation should either skip expression indexes "
+                    "or provide a custom implementation.",
+                    sig.const,
+                )
+
+        if m_sig.column_names != r_sig.column_names:
+            msg.append(
+                f"expression {r_sig.column_names} to {m_sig.column_names}"
+            )
+
+        if msg:
+            return ComparisonResult.Different(msg)
+        else:
+            return ComparisonResult.Equal()
+
+    def compare_unique_constraint(
+        self,
+        metadata_constraint: UniqueConstraint,
+        reflected_constraint: UniqueConstraint,
+    ) -> ComparisonResult:
+        """Compare two unique constraints by comparing the two signatures.
+
+        The arguments are two tuples that contain the unique constraint and
+        the signatures generated by ``create_unique_constraint_sig``.
+
+        This method returns a ``ComparisonResult``.
+        """
+        metadata_tup = self._create_metadata_constraint_sig(
+            metadata_constraint
+        )
+        reflected_tup = self._create_reflected_constraint_sig(
+            reflected_constraint
+        )
+
+        meta_sig = metadata_tup.unnamed
+        conn_sig = reflected_tup.unnamed
+        if conn_sig != meta_sig:
+            return ComparisonResult.Different(
+                f"expression {conn_sig} to {meta_sig}"
+            )
+        else:
+            return ComparisonResult.Equal()
+
+    def _skip_functional_indexes(self, metadata_indexes, conn_indexes):
+        conn_indexes_by_name = {c.name: c for c in conn_indexes}
+
+        for idx in list(metadata_indexes):
+            if idx.name in conn_indexes_by_name:
+                continue
+            iex = sqla_compat.is_expression_index(idx)
+            if iex:
+                util.warn(
+                    "autogenerate skipping metadata-specified "
+                    "expression-based index "
+                    f"{idx.name!r}; dialect {self.__dialect__!r} under "
+                    f"SQLAlchemy {sqla_compat.sqlalchemy_version} can't "
+                    "reflect these indexes so they can't be compared"
+                )
+                metadata_indexes.discard(idx)
+
+    def adjust_reflected_dialect_options(
+        self, reflected_object: Dict[str, Any], kind: str
+    ) -> Dict[str, Any]:
+        return reflected_object.get("dialect_options", {})
+
+
+class Params(NamedTuple):
+    token0: str
+    tokens: List[str]
+    args: List[str]
+    kwargs: Dict[str, str]
+
+
+def _compare_identity_options(
+    metadata_io: Union[schema.Identity, schema.Sequence, None],
+    inspector_io: Union[schema.Identity, schema.Sequence, None],
+    default_io: Union[schema.Identity, schema.Sequence],
+    skip: Set[str],
+):
+    # this can be used for identity or sequence compare.
+    # default_io is an instance of IdentityOption with all attributes to the
+    # default value.
+    meta_d = sqla_compat._get_identity_options_dict(metadata_io)
+    insp_d = sqla_compat._get_identity_options_dict(inspector_io)
+
+    diff = set()
+    ignored_attr = set()
+
+    def check_dicts(
+        meta_dict: Mapping[str, Any],
+        insp_dict: Mapping[str, Any],
+        default_dict: Mapping[str, Any],
+        attrs: Iterable[str],
+    ):
+        for attr in set(attrs).difference(skip):
+            meta_value = meta_dict.get(attr)
+            insp_value = insp_dict.get(attr)
+            if insp_value != meta_value:
+                default_value = default_dict.get(attr)
+                if meta_value == default_value:
+                    ignored_attr.add(attr)
+                else:
+                    diff.add(attr)
+
+    check_dicts(
+        meta_d,
+        insp_d,
+        sqla_compat._get_identity_options_dict(default_io),
+        set(meta_d).union(insp_d),
+    )
+    if sqla_compat.identity_has_dialect_kwargs:
+        # use only the dialect kwargs in inspector_io since metadata_io
+        # can have options for many backends
+        check_dicts(
+            getattr(metadata_io, "dialect_kwargs", {}),
+            getattr(inspector_io, "dialect_kwargs", {}),
+            default_io.dialect_kwargs,  # type: ignore[union-attr]
+            getattr(inspector_io, "dialect_kwargs", {}),
+        )
+
+    return diff, ignored_attr

.venv2/Lib/site-packages/alembic/ddl/mssql.py

@@ -0,0 +1,419 @@
+# mypy: allow-untyped-defs, allow-incomplete-defs, allow-untyped-calls
+# mypy: no-warn-return-any, allow-any-generics
+
+from __future__ import annotations
+
+import re
+from typing import Any
+from typing import Dict
+from typing import List
+from typing import Optional
+from typing import TYPE_CHECKING
+from typing import Union
+
+from sqlalchemy import types as sqltypes
+from sqlalchemy.schema import Column
+from sqlalchemy.schema import CreateIndex
+from sqlalchemy.sql.base import Executable
+from sqlalchemy.sql.elements import ClauseElement
+
+from .base import AddColumn
+from .base import alter_column
+from .base import alter_table
+from .base import ColumnDefault
+from .base import ColumnName
+from .base import ColumnNullable
+from .base import ColumnType
+from .base import format_column_name
+from .base import format_server_default
+from .base import format_table_name
+from .base import format_type
+from .base import RenameTable
+from .impl import DefaultImpl
+from .. import util
+from ..util import sqla_compat
+from ..util.sqla_compat import compiles
+
+if TYPE_CHECKING:
+    from typing import Literal
+
+    from sqlalchemy.dialects.mssql.base import MSDDLCompiler
+    from sqlalchemy.dialects.mssql.base import MSSQLCompiler
+    from sqlalchemy.engine.cursor import CursorResult
+    from sqlalchemy.sql.schema import Index
+    from sqlalchemy.sql.schema import Table
+    from sqlalchemy.sql.selectable import TableClause
+    from sqlalchemy.sql.type_api import TypeEngine
+
+    from .base import _ServerDefault
+
+
+class MSSQLImpl(DefaultImpl):
+    __dialect__ = "mssql"
+    transactional_ddl = True
+    batch_separator = "GO"
+
+    type_synonyms = DefaultImpl.type_synonyms + ({"VARCHAR", "NVARCHAR"},)
+    identity_attrs_ignore = DefaultImpl.identity_attrs_ignore + (
+        "minvalue",
+        "maxvalue",
+        "nominvalue",
+        "nomaxvalue",
+        "cycle",
+        "cache",
+    )
+
+    def __init__(self, *arg, **kw) -> None:
+        super().__init__(*arg, **kw)
+        self.batch_separator = self.context_opts.get(
+            "mssql_batch_separator", self.batch_separator
+        )
+
+    def _exec(self, construct: Any, *args, **kw) -> Optional[CursorResult]:
+        result = super()._exec(construct, *args, **kw)
+        if self.as_sql and self.batch_separator:
+            self.static_output(self.batch_separator)
+        return result
+
+    def emit_begin(self) -> None:
+        self.static_output("BEGIN TRANSACTION" + self.command_terminator)
+
+    def emit_commit(self) -> None:
+        super().emit_commit()
+        if self.as_sql and self.batch_separator:
+            self.static_output(self.batch_separator)
+
+    def alter_column(  # type:ignore[override]
+        self,
+        table_name: str,
+        column_name: str,
+        nullable: Optional[bool] = None,
+        server_default: Optional[
+            Union[_ServerDefault, Literal[False]]
+        ] = False,
+        name: Optional[str] = None,
+        type_: Optional[TypeEngine] = None,
+        schema: Optional[str] = None,
+        existing_type: Optional[TypeEngine] = None,
+        existing_server_default: Optional[_ServerDefault] = None,
+        existing_nullable: Optional[bool] = None,
+        **kw: Any,
+    ) -> None:
+        if nullable is not None:
+            if type_ is not None:
+                # the NULL/NOT NULL alter will handle
+                # the type alteration
+                existing_type = type_
+                type_ = None
+            elif existing_type is None:
+                raise util.CommandError(
+                    "MS-SQL ALTER COLUMN operations "
+                    "with NULL or NOT NULL require the "
+                    "existing_type or a new type_ be passed."
+                )
+        elif existing_nullable is not None and type_ is not None:
+            nullable = existing_nullable
+
+            # the NULL/NOT NULL alter will handle
+            # the type alteration
+            existing_type = type_
+            type_ = None
+
+        elif type_ is not None:
+            util.warn(
+                "MS-SQL ALTER COLUMN operations that specify type_= "
+                "should also specify a nullable= or "
+                "existing_nullable= argument to avoid implicit conversion "
+                "of NOT NULL columns to NULL."
+            )
+
+        used_default = False
+        if sqla_compat._server_default_is_identity(
+            server_default, existing_server_default
+        ) or sqla_compat._server_default_is_computed(
+            server_default, existing_server_default
+        ):
+            used_default = True
+            kw["server_default"] = server_default
+            kw["existing_server_default"] = existing_server_default
+
+        super().alter_column(
+            table_name,
+            column_name,
+            nullable=nullable,
+            type_=type_,
+            schema=schema,
+            existing_type=existing_type,
+            existing_nullable=existing_nullable,
+            **kw,
+        )
+
+        if server_default is not False and used_default is False:
+            if existing_server_default is not False or server_default is None:
+                self._exec(
+                    _ExecDropConstraint(
+                        table_name,
+                        column_name,
+                        "sys.default_constraints",
+                        schema,
+                    )
+                )
+            if server_default is not None:
+                super().alter_column(
+                    table_name,
+                    column_name,
+                    schema=schema,
+                    server_default=server_default,
+                )
+
+        if name is not None:
+            super().alter_column(
+                table_name, column_name, schema=schema, name=name
+            )
+
+    def create_index(self, index: Index, **kw: Any) -> None:
+        # this likely defaults to None if not present, so get()
+        # should normally not return the default value.  being
+        # defensive in any case
+        mssql_include = index.kwargs.get("mssql_include", None) or ()
+        assert index.table is not None
+        for col in mssql_include:
+            if col not in index.table.c:
+                index.table.append_column(Column(col, sqltypes.NullType))
+        self._exec(CreateIndex(index, **kw))
+
+    def bulk_insert(  # type:ignore[override]
+        self, table: Union[TableClause, Table], rows: List[dict], **kw: Any
+    ) -> None:
+        if self.as_sql:
+            self._exec(
+                "SET IDENTITY_INSERT %s ON"
+                % self.dialect.identifier_preparer.format_table(table)
+            )
+            super().bulk_insert(table, rows, **kw)
+            self._exec(
+                "SET IDENTITY_INSERT %s OFF"
+                % self.dialect.identifier_preparer.format_table(table)
+            )
+        else:
+            super().bulk_insert(table, rows, **kw)
+
+    def drop_column(
+        self,
+        table_name: str,
+        column: Column[Any],
+        schema: Optional[str] = None,
+        **kw,
+    ) -> None:
+        drop_default = kw.pop("mssql_drop_default", False)
+        if drop_default:
+            self._exec(
+                _ExecDropConstraint(
+                    table_name, column, "sys.default_constraints", schema
+                )
+            )
+        drop_check = kw.pop("mssql_drop_check", False)
+        if drop_check:
+            self._exec(
+                _ExecDropConstraint(
+                    table_name, column, "sys.check_constraints", schema
+                )
+            )
+        drop_fks = kw.pop("mssql_drop_foreign_key", False)
+        if drop_fks:
+            self._exec(_ExecDropFKConstraint(table_name, column, schema))
+        super().drop_column(table_name, column, schema=schema, **kw)
+
+    def compare_server_default(
+        self,
+        inspector_column,
+        metadata_column,
+        rendered_metadata_default,
+        rendered_inspector_default,
+    ):
+        if rendered_metadata_default is not None:
+            rendered_metadata_default = re.sub(
+                r"[\(\) \"\']", "", rendered_metadata_default
+            )
+
+        if rendered_inspector_default is not None:
+            # SQL Server collapses whitespace and adds arbitrary parenthesis
+            # within expressions.   our only option is collapse all of it
+
+            rendered_inspector_default = re.sub(
+                r"[\(\) \"\']", "", rendered_inspector_default
+            )
+
+        return rendered_inspector_default != rendered_metadata_default
+
+    def _compare_identity_default(self, metadata_identity, inspector_identity):
+        diff, ignored, is_alter = super()._compare_identity_default(
+            metadata_identity, inspector_identity
+        )
+
+        if (
+            metadata_identity is None
+            and inspector_identity is not None
+            and not diff
+            and inspector_identity.column is not None
+            and inspector_identity.column.primary_key
+        ):
+            # mssql reflect primary keys with autoincrement as identity
+            # columns. if no different attributes are present ignore them
+            is_alter = False
+
+        return diff, ignored, is_alter
+
+    def adjust_reflected_dialect_options(
+        self, reflected_object: Dict[str, Any], kind: str
+    ) -> Dict[str, Any]:
+        options: Dict[str, Any]
+        options = reflected_object.get("dialect_options", {}).copy()
+        if not options.get("mssql_include"):
+            options.pop("mssql_include", None)
+        if not options.get("mssql_clustered"):
+            options.pop("mssql_clustered", None)
+        return options
+
+
+class _ExecDropConstraint(Executable, ClauseElement):
+    inherit_cache = False
+
+    def __init__(
+        self,
+        tname: str,
+        colname: Union[Column[Any], str],
+        type_: str,
+        schema: Optional[str],
+    ) -> None:
+        self.tname = tname
+        self.colname = colname
+        self.type_ = type_
+        self.schema = schema
+
+
+class _ExecDropFKConstraint(Executable, ClauseElement):
+    inherit_cache = False
+
+    def __init__(
+        self, tname: str, colname: Column[Any], schema: Optional[str]
+    ) -> None:
+        self.tname = tname
+        self.colname = colname
+        self.schema = schema
+
+
+@compiles(_ExecDropConstraint, "mssql")
+def _exec_drop_col_constraint(
+    element: _ExecDropConstraint, compiler: MSSQLCompiler, **kw
+) -> str:
+    schema, tname, colname, type_ = (
+        element.schema,
+        element.tname,
+        element.colname,
+        element.type_,
+    )
+    # from http://www.mssqltips.com/sqlservertip/1425/\
+    # working-with-default-constraints-in-sql-server/
+    return """declare @const_name varchar(256)
+select @const_name = QUOTENAME([name]) from %(type)s
+where parent_object_id = object_id('%(schema_dot)s%(tname)s')
+and col_name(parent_object_id, parent_column_id) = '%(colname)s'
+exec('alter table %(tname_quoted)s drop constraint ' + @const_name)""" % {
+        "type": type_,
+        "tname": tname,
+        "colname": colname,
+        "tname_quoted": format_table_name(compiler, tname, schema),
+        "schema_dot": schema + "." if schema else "",
+    }
+
+
+@compiles(_ExecDropFKConstraint, "mssql")
+def _exec_drop_col_fk_constraint(
+    element: _ExecDropFKConstraint, compiler: MSSQLCompiler, **kw
+) -> str:
+    schema, tname, colname = element.schema, element.tname, element.colname
+
+    return """declare @const_name varchar(256)
+select @const_name = QUOTENAME([name]) from
+sys.foreign_keys fk join sys.foreign_key_columns fkc
+on fk.object_id=fkc.constraint_object_id
+where fkc.parent_object_id = object_id('%(schema_dot)s%(tname)s')
+and col_name(fkc.parent_object_id, fkc.parent_column_id) = '%(colname)s'
+exec('alter table %(tname_quoted)s drop constraint ' + @const_name)""" % {
+        "tname": tname,
+        "colname": colname,
+        "tname_quoted": format_table_name(compiler, tname, schema),
+        "schema_dot": schema + "." if schema else "",
+    }
+
+
+@compiles(AddColumn, "mssql")
+def visit_add_column(element: AddColumn, compiler: MSDDLCompiler, **kw) -> str:
+    return "%s %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        mssql_add_column(compiler, element.column, **kw),
+    )
+
+
+def mssql_add_column(
+    compiler: MSDDLCompiler, column: Column[Any], **kw
+) -> str:
+    return "ADD %s" % compiler.get_column_specification(column, **kw)
+
+
+@compiles(ColumnNullable, "mssql")
+def visit_column_nullable(
+    element: ColumnNullable, compiler: MSDDLCompiler, **kw
+) -> str:
+    return "%s %s %s %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        alter_column(compiler, element.column_name),
+        format_type(compiler, element.existing_type),  # type: ignore[arg-type]
+        "NULL" if element.nullable else "NOT NULL",
+    )
+
+
+@compiles(ColumnDefault, "mssql")
+def visit_column_default(
+    element: ColumnDefault, compiler: MSDDLCompiler, **kw
+) -> str:
+    # TODO: there can also be a named constraint
+    # with ADD CONSTRAINT here
+    return "%s ADD DEFAULT %s FOR %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        format_server_default(compiler, element.default),
+        format_column_name(compiler, element.column_name),
+    )
+
+
+@compiles(ColumnName, "mssql")
+def visit_rename_column(
+    element: ColumnName, compiler: MSDDLCompiler, **kw
+) -> str:
+    return "EXEC sp_rename '%s.%s', %s, 'COLUMN'" % (
+        format_table_name(compiler, element.table_name, element.schema),
+        format_column_name(compiler, element.column_name),
+        format_column_name(compiler, element.newname),
+    )
+
+
+@compiles(ColumnType, "mssql")
+def visit_column_type(
+    element: ColumnType, compiler: MSDDLCompiler, **kw
+) -> str:
+    return "%s %s %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        alter_column(compiler, element.column_name),
+        format_type(compiler, element.type_),
+    )
+
+
+@compiles(RenameTable, "mssql")
+def visit_rename_table(
+    element: RenameTable, compiler: MSDDLCompiler, **kw
+) -> str:
+    return "EXEC sp_rename '%s', %s" % (
+        format_table_name(compiler, element.table_name, element.schema),
+        format_table_name(compiler, element.new_table_name, None),
+    )

.venv2/Lib/site-packages/alembic/ddl/mysql.py

@@ -0,0 +1,474 @@
+# mypy: allow-untyped-defs, allow-incomplete-defs, allow-untyped-calls
+# mypy: no-warn-return-any, allow-any-generics
+
+from __future__ import annotations
+
+import re
+from typing import Any
+from typing import Optional
+from typing import TYPE_CHECKING
+from typing import Union
+
+from sqlalchemy import schema
+from sqlalchemy import types as sqltypes
+
+from .base import alter_table
+from .base import AlterColumn
+from .base import ColumnDefault
+from .base import ColumnName
+from .base import ColumnNullable
+from .base import ColumnType
+from .base import format_column_name
+from .base import format_server_default
+from .impl import DefaultImpl
+from .. import util
+from ..util import sqla_compat
+from ..util.sqla_compat import _is_mariadb
+from ..util.sqla_compat import _is_type_bound
+from ..util.sqla_compat import compiles
+
+if TYPE_CHECKING:
+    from typing import Literal
+
+    from sqlalchemy.dialects.mysql.base import MySQLDDLCompiler
+    from sqlalchemy.sql.ddl import DropConstraint
+    from sqlalchemy.sql.schema import Constraint
+    from sqlalchemy.sql.type_api import TypeEngine
+
+    from .base import _ServerDefault
+
+
+class MySQLImpl(DefaultImpl):
+    __dialect__ = "mysql"
+
+    transactional_ddl = False
+    type_synonyms = DefaultImpl.type_synonyms + (
+        {"BOOL", "TINYINT"},
+        {"JSON", "LONGTEXT"},
+    )
+    type_arg_extract = [r"character set ([\w\-_]+)", r"collate ([\w\-_]+)"]
+
+    def alter_column(  # type:ignore[override]
+        self,
+        table_name: str,
+        column_name: str,
+        nullable: Optional[bool] = None,
+        server_default: Union[_ServerDefault, Literal[False]] = False,
+        name: Optional[str] = None,
+        type_: Optional[TypeEngine] = None,
+        schema: Optional[str] = None,
+        existing_type: Optional[TypeEngine] = None,
+        existing_server_default: Optional[_ServerDefault] = None,
+        existing_nullable: Optional[bool] = None,
+        autoincrement: Optional[bool] = None,
+        existing_autoincrement: Optional[bool] = None,
+        comment: Optional[Union[str, Literal[False]]] = False,
+        existing_comment: Optional[str] = None,
+        **kw: Any,
+    ) -> None:
+        if sqla_compat._server_default_is_identity(
+            server_default, existing_server_default
+        ) or sqla_compat._server_default_is_computed(
+            server_default, existing_server_default
+        ):
+            # modifying computed or identity columns is not supported
+            # the default will raise
+            super().alter_column(
+                table_name,
+                column_name,
+                nullable=nullable,
+                type_=type_,
+                schema=schema,
+                existing_type=existing_type,
+                existing_nullable=existing_nullable,
+                server_default=server_default,
+                existing_server_default=existing_server_default,
+                **kw,
+            )
+        if name is not None or self._is_mysql_allowed_functional_default(
+            type_ if type_ is not None else existing_type, server_default
+        ):
+            self._exec(
+                MySQLChangeColumn(
+                    table_name,
+                    column_name,
+                    schema=schema,
+                    newname=name if name is not None else column_name,
+                    nullable=nullable
+                    if nullable is not None
+                    else existing_nullable
+                    if existing_nullable is not None
+                    else True,
+                    type_=type_ if type_ is not None else existing_type,
+                    default=server_default
+                    if server_default is not False
+                    else existing_server_default,
+                    autoincrement=autoincrement
+                    if autoincrement is not None
+                    else existing_autoincrement,
+                    comment=comment
+                    if comment is not False
+                    else existing_comment,
+                )
+            )
+        elif (
+            nullable is not None
+            or type_ is not None
+            or autoincrement is not None
+            or comment is not False
+        ):
+            self._exec(
+                MySQLModifyColumn(
+                    table_name,
+                    column_name,
+                    schema=schema,
+                    newname=name if name is not None else column_name,
+                    nullable=nullable
+                    if nullable is not None
+                    else existing_nullable
+                    if existing_nullable is not None
+                    else True,
+                    type_=type_ if type_ is not None else existing_type,
+                    default=server_default
+                    if server_default is not False
+                    else existing_server_default,
+                    autoincrement=autoincrement
+                    if autoincrement is not None
+                    else existing_autoincrement,
+                    comment=comment
+                    if comment is not False
+                    else existing_comment,
+                )
+            )
+        elif server_default is not False:
+            self._exec(
+                MySQLAlterDefault(
+                    table_name, column_name, server_default, schema=schema
+                )
+            )
+
+    def drop_constraint(
+        self,
+        const: Constraint,
+    ) -> None:
+        if isinstance(const, schema.CheckConstraint) and _is_type_bound(const):
+            return
+
+        super().drop_constraint(const)
+
+    def _is_mysql_allowed_functional_default(
+        self,
+        type_: Optional[TypeEngine],
+        server_default: Union[_ServerDefault, Literal[False]],
+    ) -> bool:
+        return (
+            type_ is not None
+            and type_._type_affinity is sqltypes.DateTime
+            and server_default is not None
+        )
+
+    def compare_server_default(
+        self,
+        inspector_column,
+        metadata_column,
+        rendered_metadata_default,
+        rendered_inspector_default,
+    ):
+        # partially a workaround for SQLAlchemy issue #3023; if the
+        # column were created without "NOT NULL", MySQL may have added
+        # an implicit default of '0' which we need to skip
+        # TODO: this is not really covered anymore ?
+        if (
+            metadata_column.type._type_affinity is sqltypes.Integer
+            and inspector_column.primary_key
+            and not inspector_column.autoincrement
+            and not rendered_metadata_default
+            and rendered_inspector_default == "'0'"
+        ):
+            return False
+        elif (
+            rendered_inspector_default
+            and inspector_column.type._type_affinity is sqltypes.Integer
+        ):
+            rendered_inspector_default = (
+                re.sub(r"^'|'$", "", rendered_inspector_default)
+                if rendered_inspector_default is not None
+                else None
+            )
+            return rendered_inspector_default != rendered_metadata_default
+        elif (
+            rendered_metadata_default
+            and metadata_column.type._type_affinity is sqltypes.String
+        ):
+            metadata_default = re.sub(r"^'|'$", "", rendered_metadata_default)
+            return rendered_inspector_default != f"'{metadata_default}'"
+        elif rendered_inspector_default and rendered_metadata_default:
+            # adjust for "function()" vs. "FUNCTION" as can occur particularly
+            # for the CURRENT_TIMESTAMP function on newer MariaDB versions
+
+            # SQLAlchemy MySQL dialect bundles ON UPDATE into the server
+            # default; adjust for this possibly being present.
+            onupdate_ins = re.match(
+                r"(.*) (on update.*?)(?:\(\))?$",
+                rendered_inspector_default.lower(),
+            )
+            onupdate_met = re.match(
+                r"(.*) (on update.*?)(?:\(\))?$",
+                rendered_metadata_default.lower(),
+            )
+
+            if onupdate_ins:
+                if not onupdate_met:
+                    return True
+                elif onupdate_ins.group(2) != onupdate_met.group(2):
+                    return True
+
+                rendered_inspector_default = onupdate_ins.group(1)
+                rendered_metadata_default = onupdate_met.group(1)
+
+            return re.sub(
+                r"(.*?)(?:\(\))?$", r"\1", rendered_inspector_default.lower()
+            ) != re.sub(
+                r"(.*?)(?:\(\))?$", r"\1", rendered_metadata_default.lower()
+            )
+        else:
+            return rendered_inspector_default != rendered_metadata_default
+
+    def correct_for_autogen_constraints(
+        self,
+        conn_unique_constraints,
+        conn_indexes,
+        metadata_unique_constraints,
+        metadata_indexes,
+    ):
+        # TODO: if SQLA 1.0, make use of "duplicates_index"
+        # metadata
+        removed = set()
+        for idx in list(conn_indexes):
+            if idx.unique:
+                continue
+            # MySQL puts implicit indexes on FK columns, even if
+            # composite and even if MyISAM, so can't check this too easily.
+            # the name of the index may be the column name or it may
+            # be the name of the FK constraint.
+            for col in idx.columns:
+                if idx.name == col.name:
+                    conn_indexes.remove(idx)
+                    removed.add(idx.name)
+                    break
+                for fk in col.foreign_keys:
+                    if fk.name == idx.name:
+                        conn_indexes.remove(idx)
+                        removed.add(idx.name)
+                        break
+                if idx.name in removed:
+                    break
+
+        # then remove indexes from the "metadata_indexes"
+        # that we've removed from reflected, otherwise they come out
+        # as adds (see #202)
+        for idx in list(metadata_indexes):
+            if idx.name in removed:
+                metadata_indexes.remove(idx)
+
+    def correct_for_autogen_foreignkeys(self, conn_fks, metadata_fks):
+        conn_fk_by_sig = {
+            self._create_reflected_constraint_sig(fk).unnamed_no_options: fk
+            for fk in conn_fks
+        }
+        metadata_fk_by_sig = {
+            self._create_metadata_constraint_sig(fk).unnamed_no_options: fk
+            for fk in metadata_fks
+        }
+
+        for sig in set(conn_fk_by_sig).intersection(metadata_fk_by_sig):
+            mdfk = metadata_fk_by_sig[sig]
+            cnfk = conn_fk_by_sig[sig]
+            # MySQL considers RESTRICT to be the default and doesn't
+            # report on it.  if the model has explicit RESTRICT and
+            # the conn FK has None, set it to RESTRICT
+            if (
+                mdfk.ondelete is not None
+                and mdfk.ondelete.lower() == "restrict"
+                and cnfk.ondelete is None
+            ):
+                cnfk.ondelete = "RESTRICT"
+            if (
+                mdfk.onupdate is not None
+                and mdfk.onupdate.lower() == "restrict"
+                and cnfk.onupdate is None
+            ):
+                cnfk.onupdate = "RESTRICT"
+
+
+class MariaDBImpl(MySQLImpl):
+    __dialect__ = "mariadb"
+
+
+class MySQLAlterDefault(AlterColumn):
+    def __init__(
+        self,
+        name: str,
+        column_name: str,
+        default: _ServerDefault,
+        schema: Optional[str] = None,
+    ) -> None:
+        super(AlterColumn, self).__init__(name, schema=schema)
+        self.column_name = column_name
+        self.default = default
+
+
+class MySQLChangeColumn(AlterColumn):
+    def __init__(
+        self,
+        name: str,
+        column_name: str,
+        schema: Optional[str] = None,
+        newname: Optional[str] = None,
+        type_: Optional[TypeEngine] = None,
+        nullable: Optional[bool] = None,
+        default: Optional[Union[_ServerDefault, Literal[False]]] = False,
+        autoincrement: Optional[bool] = None,
+        comment: Optional[Union[str, Literal[False]]] = False,
+    ) -> None:
+        super(AlterColumn, self).__init__(name, schema=schema)
+        self.column_name = column_name
+        self.nullable = nullable
+        self.newname = newname
+        self.default = default
+        self.autoincrement = autoincrement
+        self.comment = comment
+        if type_ is None:
+            raise util.CommandError(
+                "All MySQL CHANGE/MODIFY COLUMN operations "
+                "require the existing type."
+            )
+
+        self.type_ = sqltypes.to_instance(type_)
+
+
+class MySQLModifyColumn(MySQLChangeColumn):
+    pass
+
+
+@compiles(ColumnNullable, "mysql", "mariadb")
+@compiles(ColumnName, "mysql", "mariadb")
+@compiles(ColumnDefault, "mysql", "mariadb")
+@compiles(ColumnType, "mysql", "mariadb")
+def _mysql_doesnt_support_individual(element, compiler, **kw):
+    raise NotImplementedError(
+        "Individual alter column constructs not supported by MySQL"
+    )
+
+
+@compiles(MySQLAlterDefault, "mysql", "mariadb")
+def _mysql_alter_default(
+    element: MySQLAlterDefault, compiler: MySQLDDLCompiler, **kw
+) -> str:
+    return "%s ALTER COLUMN %s %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        format_column_name(compiler, element.column_name),
+        "SET DEFAULT %s" % format_server_default(compiler, element.default)
+        if element.default is not None
+        else "DROP DEFAULT",
+    )
+
+
+@compiles(MySQLModifyColumn, "mysql", "mariadb")
+def _mysql_modify_column(
+    element: MySQLModifyColumn, compiler: MySQLDDLCompiler, **kw
+) -> str:
+    return "%s MODIFY %s %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        format_column_name(compiler, element.column_name),
+        _mysql_colspec(
+            compiler,
+            nullable=element.nullable,
+            server_default=element.default,
+            type_=element.type_,
+            autoincrement=element.autoincrement,
+            comment=element.comment,
+        ),
+    )
+
+
+@compiles(MySQLChangeColumn, "mysql", "mariadb")
+def _mysql_change_column(
+    element: MySQLChangeColumn, compiler: MySQLDDLCompiler, **kw
+) -> str:
+    return "%s CHANGE %s %s %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        format_column_name(compiler, element.column_name),
+        format_column_name(compiler, element.newname),
+        _mysql_colspec(
+            compiler,
+            nullable=element.nullable,
+            server_default=element.default,
+            type_=element.type_,
+            autoincrement=element.autoincrement,
+            comment=element.comment,
+        ),
+    )
+
+
+def _mysql_colspec(
+    compiler: MySQLDDLCompiler,
+    nullable: Optional[bool],
+    server_default: Optional[Union[_ServerDefault, Literal[False]]],
+    type_: TypeEngine,
+    autoincrement: Optional[bool],
+    comment: Optional[Union[str, Literal[False]]],
+) -> str:
+    spec = "%s %s" % (
+        compiler.dialect.type_compiler.process(type_),
+        "NULL" if nullable else "NOT NULL",
+    )
+    if autoincrement:
+        spec += " AUTO_INCREMENT"
+    if server_default is not False and server_default is not None:
+        spec += " DEFAULT %s" % format_server_default(compiler, server_default)
+    if comment:
+        spec += " COMMENT %s" % compiler.sql_compiler.render_literal_value(
+            comment, sqltypes.String()
+        )
+
+    return spec
+
+
+@compiles(schema.DropConstraint, "mysql", "mariadb")
+def _mysql_drop_constraint(
+    element: DropConstraint, compiler: MySQLDDLCompiler, **kw
+) -> str:
+    """Redefine SQLAlchemy's drop constraint to
+    raise errors for invalid constraint type."""
+
+    constraint = element.element
+    if isinstance(
+        constraint,
+        (
+            schema.ForeignKeyConstraint,
+            schema.PrimaryKeyConstraint,
+            schema.UniqueConstraint,
+        ),
+    ):
+        assert not kw
+        return compiler.visit_drop_constraint(element)
+    elif isinstance(constraint, schema.CheckConstraint):
+        # note that SQLAlchemy as of 1.2 does not yet support
+        # DROP CONSTRAINT for MySQL/MariaDB, so we implement fully
+        # here.
+        if _is_mariadb(compiler.dialect):
+            return "ALTER TABLE %s DROP CONSTRAINT %s" % (
+                compiler.preparer.format_table(constraint.table),
+                compiler.preparer.format_constraint(constraint),
+            )
+        else:
+            return "ALTER TABLE %s DROP CHECK %s" % (
+                compiler.preparer.format_table(constraint.table),
+                compiler.preparer.format_constraint(constraint),
+            )
+    else:
+        raise NotImplementedError(
+            "No generic 'DROP CONSTRAINT' in MySQL - "
+            "please specify constraint type"
+        )

.venv2/Lib/site-packages/alembic/ddl/oracle.py

@@ -0,0 +1,200 @@
+# mypy: allow-untyped-defs, allow-incomplete-defs, allow-untyped-calls
+# mypy: no-warn-return-any, allow-any-generics
+
+from __future__ import annotations
+
+import re
+from typing import Any
+from typing import Optional
+from typing import TYPE_CHECKING
+
+from sqlalchemy.sql import sqltypes
+
+from .base import AddColumn
+from .base import alter_table
+from .base import ColumnComment
+from .base import ColumnDefault
+from .base import ColumnName
+from .base import ColumnNullable
+from .base import ColumnType
+from .base import format_column_name
+from .base import format_server_default
+from .base import format_table_name
+from .base import format_type
+from .base import IdentityColumnDefault
+from .base import RenameTable
+from .impl import DefaultImpl
+from ..util.sqla_compat import compiles
+
+if TYPE_CHECKING:
+    from sqlalchemy.dialects.oracle.base import OracleDDLCompiler
+    from sqlalchemy.engine.cursor import CursorResult
+    from sqlalchemy.sql.schema import Column
+
+
+class OracleImpl(DefaultImpl):
+    __dialect__ = "oracle"
+    transactional_ddl = False
+    batch_separator = "/"
+    command_terminator = ""
+    type_synonyms = DefaultImpl.type_synonyms + (
+        {"VARCHAR", "VARCHAR2"},
+        {"BIGINT", "INTEGER", "SMALLINT", "DECIMAL", "NUMERIC", "NUMBER"},
+        {"DOUBLE", "FLOAT", "DOUBLE_PRECISION"},
+    )
+    identity_attrs_ignore = ()
+
+    def __init__(self, *arg, **kw) -> None:
+        super().__init__(*arg, **kw)
+        self.batch_separator = self.context_opts.get(
+            "oracle_batch_separator", self.batch_separator
+        )
+
+    def _exec(self, construct: Any, *args, **kw) -> Optional[CursorResult]:
+        result = super()._exec(construct, *args, **kw)
+        if self.as_sql and self.batch_separator:
+            self.static_output(self.batch_separator)
+        return result
+
+    def compare_server_default(
+        self,
+        inspector_column,
+        metadata_column,
+        rendered_metadata_default,
+        rendered_inspector_default,
+    ):
+        if rendered_metadata_default is not None:
+            rendered_metadata_default = re.sub(
+                r"^\((.+)\)$", r"\1", rendered_metadata_default
+            )
+
+            rendered_metadata_default = re.sub(
+                r"^\"?'(.+)'\"?$", r"\1", rendered_metadata_default
+            )
+
+        if rendered_inspector_default is not None:
+            rendered_inspector_default = re.sub(
+                r"^\((.+)\)$", r"\1", rendered_inspector_default
+            )
+
+            rendered_inspector_default = re.sub(
+                r"^\"?'(.+)'\"?$", r"\1", rendered_inspector_default
+            )
+
+            rendered_inspector_default = rendered_inspector_default.strip()
+        return rendered_inspector_default != rendered_metadata_default
+
+    def emit_begin(self) -> None:
+        self._exec("SET TRANSACTION READ WRITE")
+
+    def emit_commit(self) -> None:
+        self._exec("COMMIT")
+
+
+@compiles(AddColumn, "oracle")
+def visit_add_column(
+    element: AddColumn, compiler: OracleDDLCompiler, **kw
+) -> str:
+    return "%s %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        add_column(compiler, element.column, **kw),
+    )
+
+
+@compiles(ColumnNullable, "oracle")
+def visit_column_nullable(
+    element: ColumnNullable, compiler: OracleDDLCompiler, **kw
+) -> str:
+    return "%s %s %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        alter_column(compiler, element.column_name),
+        "NULL" if element.nullable else "NOT NULL",
+    )
+
+
+@compiles(ColumnType, "oracle")
+def visit_column_type(
+    element: ColumnType, compiler: OracleDDLCompiler, **kw
+) -> str:
+    return "%s %s %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        alter_column(compiler, element.column_name),
+        "%s" % format_type(compiler, element.type_),
+    )
+
+
+@compiles(ColumnName, "oracle")
+def visit_column_name(
+    element: ColumnName, compiler: OracleDDLCompiler, **kw
+) -> str:
+    return "%s RENAME COLUMN %s TO %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        format_column_name(compiler, element.column_name),
+        format_column_name(compiler, element.newname),
+    )
+
+
+@compiles(ColumnDefault, "oracle")
+def visit_column_default(
+    element: ColumnDefault, compiler: OracleDDLCompiler, **kw
+) -> str:
+    return "%s %s %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        alter_column(compiler, element.column_name),
+        "DEFAULT %s" % format_server_default(compiler, element.default)
+        if element.default is not None
+        else "DEFAULT NULL",
+    )
+
+
+@compiles(ColumnComment, "oracle")
+def visit_column_comment(
+    element: ColumnComment, compiler: OracleDDLCompiler, **kw
+) -> str:
+    ddl = "COMMENT ON COLUMN {table_name}.{column_name} IS {comment}"
+
+    comment = compiler.sql_compiler.render_literal_value(
+        (element.comment if element.comment is not None else ""),
+        sqltypes.String(),
+    )
+
+    return ddl.format(
+        table_name=element.table_name,
+        column_name=element.column_name,
+        comment=comment,
+    )
+
+
+@compiles(RenameTable, "oracle")
+def visit_rename_table(
+    element: RenameTable, compiler: OracleDDLCompiler, **kw
+) -> str:
+    return "%s RENAME TO %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        format_table_name(compiler, element.new_table_name, None),
+    )
+
+
+def alter_column(compiler: OracleDDLCompiler, name: str) -> str:
+    return "MODIFY %s" % format_column_name(compiler, name)
+
+
+def add_column(compiler: OracleDDLCompiler, column: Column[Any], **kw) -> str:
+    return "ADD %s" % compiler.get_column_specification(column, **kw)
+
+
+@compiles(IdentityColumnDefault, "oracle")
+def visit_identity_column(
+    element: IdentityColumnDefault, compiler: OracleDDLCompiler, **kw
+):
+    text = "%s %s " % (
+        alter_table(compiler, element.table_name, element.schema),
+        alter_column(compiler, element.column_name),
+    )
+    if element.default is None:
+        # drop identity
+        text += "DROP IDENTITY"
+        return text
+    else:
+        text += compiler.visit_identity_column(element.default)
+        return text

.venv2/Lib/site-packages/alembic/ddl/postgresql.py

@@ -0,0 +1,848 @@
+# mypy: allow-untyped-defs, allow-incomplete-defs, allow-untyped-calls
+# mypy: no-warn-return-any, allow-any-generics
+
+from __future__ import annotations
+
+import logging
+import re
+from typing import Any
+from typing import cast
+from typing import Dict
+from typing import List
+from typing import Optional
+from typing import Sequence
+from typing import Tuple
+from typing import TYPE_CHECKING
+from typing import Union
+
+from sqlalchemy import Column
+from sqlalchemy import literal_column
+from sqlalchemy import Numeric
+from sqlalchemy import text
+from sqlalchemy import types as sqltypes
+from sqlalchemy.dialects.postgresql import BIGINT
+from sqlalchemy.dialects.postgresql import ExcludeConstraint
+from sqlalchemy.dialects.postgresql import INTEGER
+from sqlalchemy.schema import CreateIndex
+from sqlalchemy.sql.elements import ColumnClause
+from sqlalchemy.sql.elements import TextClause
+from sqlalchemy.sql.functions import FunctionElement
+from sqlalchemy.types import NULLTYPE
+
+from .base import alter_column
+from .base import alter_table
+from .base import AlterColumn
+from .base import ColumnComment
+from .base import format_column_name
+from .base import format_table_name
+from .base import format_type
+from .base import IdentityColumnDefault
+from .base import RenameTable
+from .impl import ComparisonResult
+from .impl import DefaultImpl
+from .. import util
+from ..autogenerate import render
+from ..operations import ops
+from ..operations import schemaobj
+from ..operations.base import BatchOperations
+from ..operations.base import Operations
+from ..util import sqla_compat
+from ..util.sqla_compat import compiles
+
+if TYPE_CHECKING:
+    from typing import Literal
+
+    from sqlalchemy import Index
+    from sqlalchemy import UniqueConstraint
+    from sqlalchemy.dialects.postgresql.array import ARRAY
+    from sqlalchemy.dialects.postgresql.base import PGDDLCompiler
+    from sqlalchemy.dialects.postgresql.hstore import HSTORE
+    from sqlalchemy.dialects.postgresql.json import JSON
+    from sqlalchemy.dialects.postgresql.json import JSONB
+    from sqlalchemy.sql.elements import ClauseElement
+    from sqlalchemy.sql.elements import ColumnElement
+    from sqlalchemy.sql.elements import quoted_name
+    from sqlalchemy.sql.schema import MetaData
+    from sqlalchemy.sql.schema import Table
+    from sqlalchemy.sql.type_api import TypeEngine
+
+    from .base import _ServerDefault
+    from ..autogenerate.api import AutogenContext
+    from ..autogenerate.render import _f_name
+    from ..runtime.migration import MigrationContext
+
+
+log = logging.getLogger(__name__)
+
+
+class PostgresqlImpl(DefaultImpl):
+    __dialect__ = "postgresql"
+    transactional_ddl = True
+    type_synonyms = DefaultImpl.type_synonyms + (
+        {"FLOAT", "DOUBLE PRECISION"},
+    )
+
+    def create_index(self, index: Index, **kw: Any) -> None:
+        # this likely defaults to None if not present, so get()
+        # should normally not return the default value.  being
+        # defensive in any case
+        postgresql_include = index.kwargs.get("postgresql_include", None) or ()
+        for col in postgresql_include:
+            if col not in index.table.c:  # type: ignore[union-attr]
+                index.table.append_column(  # type: ignore[union-attr]
+                    Column(col, sqltypes.NullType)
+                )
+        self._exec(CreateIndex(index, **kw))
+
+    def prep_table_for_batch(self, batch_impl, table):
+        for constraint in table.constraints:
+            if (
+                constraint.name is not None
+                and constraint.name in batch_impl.named_constraints
+            ):
+                self.drop_constraint(constraint)
+
+    def compare_server_default(
+        self,
+        inspector_column,
+        metadata_column,
+        rendered_metadata_default,
+        rendered_inspector_default,
+    ):
+        # don't do defaults for SERIAL columns
+        if (
+            metadata_column.primary_key
+            and metadata_column is metadata_column.table._autoincrement_column
+        ):
+            return False
+
+        conn_col_default = rendered_inspector_default
+
+        defaults_equal = conn_col_default == rendered_metadata_default
+        if defaults_equal:
+            return False
+
+        if None in (
+            conn_col_default,
+            rendered_metadata_default,
+            metadata_column.server_default,
+        ):
+            return not defaults_equal
+
+        metadata_default = metadata_column.server_default.arg
+
+        if isinstance(metadata_default, str):
+            if not isinstance(inspector_column.type, Numeric):
+                metadata_default = re.sub(r"^'|'$", "", metadata_default)
+                metadata_default = f"'{metadata_default}'"
+
+            metadata_default = literal_column(metadata_default)
+
+        # run a real compare against the server
+        conn = self.connection
+        assert conn is not None
+        return not conn.scalar(
+            sqla_compat._select(
+                literal_column(conn_col_default) == metadata_default
+            )
+        )
+
+    def alter_column(  # type:ignore[override]
+        self,
+        table_name: str,
+        column_name: str,
+        nullable: Optional[bool] = None,
+        server_default: Union[_ServerDefault, Literal[False]] = False,
+        name: Optional[str] = None,
+        type_: Optional[TypeEngine] = None,
+        schema: Optional[str] = None,
+        autoincrement: Optional[bool] = None,
+        existing_type: Optional[TypeEngine] = None,
+        existing_server_default: Optional[_ServerDefault] = None,
+        existing_nullable: Optional[bool] = None,
+        existing_autoincrement: Optional[bool] = None,
+        **kw: Any,
+    ) -> None:
+        using = kw.pop("postgresql_using", None)
+
+        if using is not None and type_ is None:
+            raise util.CommandError(
+                "postgresql_using must be used with the type_ parameter"
+            )
+
+        if type_ is not None:
+            self._exec(
+                PostgresqlColumnType(
+                    table_name,
+                    column_name,
+                    type_,
+                    schema=schema,
+                    using=using,
+                    existing_type=existing_type,
+                    existing_server_default=existing_server_default,
+                    existing_nullable=existing_nullable,
+                )
+            )
+
+        super().alter_column(
+            table_name,
+            column_name,
+            nullable=nullable,
+            server_default=server_default,
+            name=name,
+            schema=schema,
+            autoincrement=autoincrement,
+            existing_type=existing_type,
+            existing_server_default=existing_server_default,
+            existing_nullable=existing_nullable,
+            existing_autoincrement=existing_autoincrement,
+            **kw,
+        )
+
+    def autogen_column_reflect(self, inspector, table, column_info):
+        if column_info.get("default") and isinstance(
+            column_info["type"], (INTEGER, BIGINT)
+        ):
+            seq_match = re.match(
+                r"nextval\('(.+?)'::regclass\)", column_info["default"]
+            )
+            if seq_match:
+                info = sqla_compat._exec_on_inspector(
+                    inspector,
+                    text(
+                        "select c.relname, a.attname "
+                        "from pg_class as c join "
+                        "pg_depend d on d.objid=c.oid and "
+                        "d.classid='pg_class'::regclass and "
+                        "d.refclassid='pg_class'::regclass "
+                        "join pg_class t on t.oid=d.refobjid "
+                        "join pg_attribute a on a.attrelid=t.oid and "
+                        "a.attnum=d.refobjsubid "
+                        "where c.relkind='S' and c.relname=:seqname"
+                    ),
+                    seqname=seq_match.group(1),
+                ).first()
+                if info:
+                    seqname, colname = info
+                    if colname == column_info["name"]:
+                        log.info(
+                            "Detected sequence named '%s' as "
+                            "owned by integer column '%s(%s)', "
+                            "assuming SERIAL and omitting",
+                            seqname,
+                            table.name,
+                            colname,
+                        )
+                        # sequence, and the owner is this column,
+                        # its a SERIAL - whack it!
+                        del column_info["default"]
+
+    def correct_for_autogen_constraints(
+        self,
+        conn_unique_constraints,
+        conn_indexes,
+        metadata_unique_constraints,
+        metadata_indexes,
+    ):
+        doubled_constraints = {
+            index
+            for index in conn_indexes
+            if index.info.get("duplicates_constraint")
+        }
+
+        for ix in doubled_constraints:
+            conn_indexes.remove(ix)
+
+        if not sqla_compat.sqla_2:
+            self._skip_functional_indexes(metadata_indexes, conn_indexes)
+
+    # pg behavior regarding modifiers
+    # | # | compiled sql     | returned sql     | regexp. group is removed |
+    # | - | ---------------- | -----------------| ------------------------ |
+    # | 1 | nulls first      | nulls first      | -                        |
+    # | 2 | nulls last       |                  | (?<! desc)( nulls last)$ |
+    # | 3 | asc              |                  | ( asc)$                  |
+    # | 4 | asc nulls first  | nulls first      | ( asc) nulls first$      |
+    # | 5 | asc nulls last   |                  | ( asc nulls last)$       |
+    # | 6 | desc             | desc             | -                        |
+    # | 7 | desc nulls first | desc             | desc( nulls first)$      |
+    # | 8 | desc nulls last  | desc nulls last  | -                        |
+    _default_modifiers_re = (  # order of case 2 and 5 matters
+        re.compile("( asc nulls last)$"),  # case 5
+        re.compile("(?<! desc)( nulls last)$"),  # case 2
+        re.compile("( asc)$"),  # case 3
+        re.compile("( asc) nulls first$"),  # case 4
+        re.compile(" desc( nulls first)$"),  # case 7
+    )
+
+    def _cleanup_index_expr(self, index: Index, expr: str) -> str:
+        expr = expr.lower().replace('"', "").replace("'", "")
+        if index.table is not None:
+            # should not be needed, since include_table=False is in compile
+            expr = expr.replace(f"{index.table.name.lower()}.", "")
+
+        if "::" in expr:
+            # strip :: cast. types can have spaces in them
+            expr = re.sub(r"(::[\w ]+\w)", "", expr)
+
+        while expr and expr[0] == "(" and expr[-1] == ")":
+            expr = expr[1:-1]
+
+        # NOTE: when parsing the connection expression this cleanup could
+        # be skipped
+        for rs in self._default_modifiers_re:
+            if match := rs.search(expr):
+                start, end = match.span(1)
+                expr = expr[:start] + expr[end:]
+                break
+
+        while expr and expr[0] == "(" and expr[-1] == ")":
+            expr = expr[1:-1]
+
+        # strip casts
+        cast_re = re.compile(r"cast\s*\(")
+        if cast_re.match(expr):
+            expr = cast_re.sub("", expr)
+            # remove the as type
+            expr = re.sub(r"as\s+[^)]+\)", "", expr)
+        # remove spaces
+        expr = expr.replace(" ", "")
+        return expr
+
+    def _dialect_options(
+        self, item: Union[Index, UniqueConstraint]
+    ) -> Tuple[Any, ...]:
+        # only the positive case is returned by sqlalchemy reflection so
+        # None and False are threated the same
+        if item.dialect_kwargs.get("postgresql_nulls_not_distinct"):
+            return ("nulls_not_distinct",)
+        return ()
+
+    def compare_indexes(
+        self,
+        metadata_index: Index,
+        reflected_index: Index,
+    ) -> ComparisonResult:
+        msg = []
+        unique_msg = self._compare_index_unique(
+            metadata_index, reflected_index
+        )
+        if unique_msg:
+            msg.append(unique_msg)
+        m_exprs = metadata_index.expressions
+        r_exprs = reflected_index.expressions
+        if len(m_exprs) != len(r_exprs):
+            msg.append(f"expression number {len(r_exprs)} to {len(m_exprs)}")
+        if msg:
+            # no point going further, return early
+            return ComparisonResult.Different(msg)
+        skip = []
+        for pos, (m_e, r_e) in enumerate(zip(m_exprs, r_exprs), 1):
+            m_compile = self._compile_element(m_e)
+            m_text = self._cleanup_index_expr(metadata_index, m_compile)
+            # print(f"META ORIG: {m_compile!r} CLEANUP: {m_text!r}")
+            r_compile = self._compile_element(r_e)
+            r_text = self._cleanup_index_expr(metadata_index, r_compile)
+            # print(f"CONN ORIG: {r_compile!r} CLEANUP: {r_text!r}")
+            if m_text == r_text:
+                continue  # expressions these are equal
+            elif m_compile.strip().endswith("_ops") and (
+                " " in m_compile or ")" in m_compile  # is an expression
+            ):
+                skip.append(
+                    f"expression #{pos} {m_compile!r} detected "
+                    "as including operator clause."
+                )
+                util.warn(
+                    f"Expression #{pos} {m_compile!r} in index "
+                    f"{reflected_index.name!r} detected to include "
+                    "an operator clause. Expression compare cannot proceed. "
+                    "Please move the operator clause to the "
+                    "``postgresql_ops`` dict to enable proper compare "
+                    "of the index expressions: "
+                    "https://docs.sqlalchemy.org/en/latest/dialects/postgresql.html#operator-classes",  # noqa: E501
+                )
+            else:
+                msg.append(f"expression #{pos} {r_compile!r} to {m_compile!r}")
+
+        m_options = self._dialect_options(metadata_index)
+        r_options = self._dialect_options(reflected_index)
+        if m_options != r_options:
+            msg.extend(f"options {r_options} to {m_options}")
+
+        if msg:
+            return ComparisonResult.Different(msg)
+        elif skip:
+            # if there are other changes detected don't skip the index
+            return ComparisonResult.Skip(skip)
+        else:
+            return ComparisonResult.Equal()
+
+    def compare_unique_constraint(
+        self,
+        metadata_constraint: UniqueConstraint,
+        reflected_constraint: UniqueConstraint,
+    ) -> ComparisonResult:
+        metadata_tup = self._create_metadata_constraint_sig(
+            metadata_constraint
+        )
+        reflected_tup = self._create_reflected_constraint_sig(
+            reflected_constraint
+        )
+
+        meta_sig = metadata_tup.unnamed
+        conn_sig = reflected_tup.unnamed
+        if conn_sig != meta_sig:
+            return ComparisonResult.Different(
+                f"expression {conn_sig} to {meta_sig}"
+            )
+
+        metadata_do = self._dialect_options(metadata_tup.const)
+        conn_do = self._dialect_options(reflected_tup.const)
+        if metadata_do != conn_do:
+            return ComparisonResult.Different(
+                f"expression {conn_do} to {metadata_do}"
+            )
+
+        return ComparisonResult.Equal()
+
+    def adjust_reflected_dialect_options(
+        self, reflected_options: Dict[str, Any], kind: str
+    ) -> Dict[str, Any]:
+        options: Dict[str, Any]
+        options = reflected_options.get("dialect_options", {}).copy()
+        if not options.get("postgresql_include"):
+            options.pop("postgresql_include", None)
+        return options
+
+    def _compile_element(self, element: Union[ClauseElement, str]) -> str:
+        if isinstance(element, str):
+            return element
+        return element.compile(
+            dialect=self.dialect,
+            compile_kwargs={"literal_binds": True, "include_table": False},
+        ).string
+
+    def render_ddl_sql_expr(
+        self,
+        expr: ClauseElement,
+        is_server_default: bool = False,
+        is_index: bool = False,
+        **kw: Any,
+    ) -> str:
+        """Render a SQL expression that is typically a server default,
+        index expression, etc.
+
+        """
+
+        # apply self_group to index expressions;
+        # see https://github.com/sqlalchemy/sqlalchemy/blob/
+        # 82fa95cfce070fab401d020c6e6e4a6a96cc2578/
+        # lib/sqlalchemy/dialects/postgresql/base.py#L2261
+        if is_index and not isinstance(expr, ColumnClause):
+            expr = expr.self_group()
+
+        return super().render_ddl_sql_expr(
+            expr, is_server_default=is_server_default, is_index=is_index, **kw
+        )
+
+    def render_type(
+        self, type_: TypeEngine, autogen_context: AutogenContext
+    ) -> Union[str, Literal[False]]:
+        mod = type(type_).__module__
+        if not mod.startswith("sqlalchemy.dialects.postgresql"):
+            return False
+
+        if hasattr(self, "_render_%s_type" % type_.__visit_name__):
+            meth = getattr(self, "_render_%s_type" % type_.__visit_name__)
+            return meth(type_, autogen_context)
+
+        return False
+
+    def _render_HSTORE_type(
+        self, type_: HSTORE, autogen_context: AutogenContext
+    ) -> str:
+        return cast(
+            str,
+            render._render_type_w_subtype(
+                type_, autogen_context, "text_type", r"(.+?\(.*text_type=)"
+            ),
+        )
+
+    def _render_ARRAY_type(
+        self, type_: ARRAY, autogen_context: AutogenContext
+    ) -> str:
+        return cast(
+            str,
+            render._render_type_w_subtype(
+                type_, autogen_context, "item_type", r"(.+?\()"
+            ),
+        )
+
+    def _render_JSON_type(
+        self, type_: JSON, autogen_context: AutogenContext
+    ) -> str:
+        return cast(
+            str,
+            render._render_type_w_subtype(
+                type_, autogen_context, "astext_type", r"(.+?\(.*astext_type=)"
+            ),
+        )
+
+    def _render_JSONB_type(
+        self, type_: JSONB, autogen_context: AutogenContext
+    ) -> str:
+        return cast(
+            str,
+            render._render_type_w_subtype(
+                type_, autogen_context, "astext_type", r"(.+?\(.*astext_type=)"
+            ),
+        )
+
+
+class PostgresqlColumnType(AlterColumn):
+    def __init__(
+        self, name: str, column_name: str, type_: TypeEngine, **kw
+    ) -> None:
+        using = kw.pop("using", None)
+        super().__init__(name, column_name, **kw)
+        self.type_ = sqltypes.to_instance(type_)
+        self.using = using
+
+
+@compiles(RenameTable, "postgresql")
+def visit_rename_table(
+    element: RenameTable, compiler: PGDDLCompiler, **kw
+) -> str:
+    return "%s RENAME TO %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        format_table_name(compiler, element.new_table_name, None),
+    )
+
+
+@compiles(PostgresqlColumnType, "postgresql")
+def visit_column_type(
+    element: PostgresqlColumnType, compiler: PGDDLCompiler, **kw
+) -> str:
+    return "%s %s %s %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        alter_column(compiler, element.column_name),
+        "TYPE %s" % format_type(compiler, element.type_),
+        "USING %s" % element.using if element.using else "",
+    )
+
+
+@compiles(ColumnComment, "postgresql")
+def visit_column_comment(
+    element: ColumnComment, compiler: PGDDLCompiler, **kw
+) -> str:
+    ddl = "COMMENT ON COLUMN {table_name}.{column_name} IS {comment}"
+    comment = (
+        compiler.sql_compiler.render_literal_value(
+            element.comment, sqltypes.String()
+        )
+        if element.comment is not None
+        else "NULL"
+    )
+
+    return ddl.format(
+        table_name=format_table_name(
+            compiler, element.table_name, element.schema
+        ),
+        column_name=format_column_name(compiler, element.column_name),
+        comment=comment,
+    )
+
+
+@compiles(IdentityColumnDefault, "postgresql")
+def visit_identity_column(
+    element: IdentityColumnDefault, compiler: PGDDLCompiler, **kw
+):
+    text = "%s %s " % (
+        alter_table(compiler, element.table_name, element.schema),
+        alter_column(compiler, element.column_name),
+    )
+    if element.default is None:
+        # drop identity
+        text += "DROP IDENTITY"
+        return text
+    elif element.existing_server_default is None:
+        # add identity options
+        text += "ADD "
+        text += compiler.visit_identity_column(element.default)
+        return text
+    else:
+        # alter identity
+        diff, _, _ = element.impl._compare_identity_default(
+            element.default, element.existing_server_default
+        )
+        identity = element.default
+        for attr in sorted(diff):
+            if attr == "always":
+                text += "SET GENERATED %s " % (
+                    "ALWAYS" if identity.always else "BY DEFAULT"
+                )
+            else:
+                text += "SET %s " % compiler.get_identity_options(
+                    sqla_compat.Identity(**{attr: getattr(identity, attr)})
+                )
+        return text
+
+
+@Operations.register_operation("create_exclude_constraint")
+@BatchOperations.register_operation(
+    "create_exclude_constraint", "batch_create_exclude_constraint"
+)
+@ops.AddConstraintOp.register_add_constraint("exclude_constraint")
+class CreateExcludeConstraintOp(ops.AddConstraintOp):
+    """Represent a create exclude constraint operation."""
+
+    constraint_type = "exclude"
+
+    def __init__(
+        self,
+        constraint_name: sqla_compat._ConstraintName,
+        table_name: Union[str, quoted_name],
+        elements: Union[
+            Sequence[Tuple[str, str]],
+            Sequence[Tuple[ColumnClause[Any], str]],
+        ],
+        where: Optional[Union[ColumnElement[bool], str]] = None,
+        schema: Optional[str] = None,
+        _orig_constraint: Optional[ExcludeConstraint] = None,
+        **kw,
+    ) -> None:
+        self.constraint_name = constraint_name
+        self.table_name = table_name
+        self.elements = elements
+        self.where = where
+        self.schema = schema
+        self._orig_constraint = _orig_constraint
+        self.kw = kw
+
+    @classmethod
+    def from_constraint(  # type:ignore[override]
+        cls, constraint: ExcludeConstraint
+    ) -> CreateExcludeConstraintOp:
+        constraint_table = sqla_compat._table_for_constraint(constraint)
+        return cls(
+            constraint.name,
+            constraint_table.name,
+            [  # type: ignore
+                (expr, op) for expr, name, op in constraint._render_exprs
+            ],
+            where=cast("ColumnElement[bool] | None", constraint.where),
+            schema=constraint_table.schema,
+            _orig_constraint=constraint,
+            deferrable=constraint.deferrable,
+            initially=constraint.initially,
+            using=constraint.using,
+        )
+
+    def to_constraint(
+        self, migration_context: Optional[MigrationContext] = None
+    ) -> ExcludeConstraint:
+        if self._orig_constraint is not None:
+            return self._orig_constraint
+        schema_obj = schemaobj.SchemaObjects(migration_context)
+        t = schema_obj.table(self.table_name, schema=self.schema)
+        excl = ExcludeConstraint(
+            *self.elements,
+            name=self.constraint_name,
+            where=self.where,
+            **self.kw,
+        )
+        for (
+            expr,
+            name,
+            oper,
+        ) in excl._render_exprs:
+            t.append_column(Column(name, NULLTYPE))
+        t.append_constraint(excl)
+        return excl
+
+    @classmethod
+    def create_exclude_constraint(
+        cls,
+        operations: Operations,
+        constraint_name: str,
+        table_name: str,
+        *elements: Any,
+        **kw: Any,
+    ) -> Optional[Table]:
+        """Issue an alter to create an EXCLUDE constraint using the
+        current migration context.
+
+        .. note::  This method is Postgresql specific, and additionally
+           requires at least SQLAlchemy 1.0.
+
+        e.g.::
+
+            from alembic import op
+
+            op.create_exclude_constraint(
+                "user_excl",
+                "user",
+                ("period", "&&"),
+                ("group", "="),
+                where=("group != 'some group'"),
+            )
+
+        Note that the expressions work the same way as that of
+        the ``ExcludeConstraint`` object itself; if plain strings are
+        passed, quoting rules must be applied manually.
+
+        :param name: Name of the constraint.
+        :param table_name: String name of the source table.
+        :param elements: exclude conditions.
+        :param where: SQL expression or SQL string with optional WHERE
+         clause.
+        :param deferrable: optional bool. If set, emit DEFERRABLE or
+         NOT DEFERRABLE when issuing DDL for this constraint.
+        :param initially: optional string. If set, emit INITIALLY <value>
+         when issuing DDL for this constraint.
+        :param schema: Optional schema name to operate within.
+
+        """
+        op = cls(constraint_name, table_name, elements, **kw)
+        return operations.invoke(op)
+
+    @classmethod
+    def batch_create_exclude_constraint(
+        cls,
+        operations: BatchOperations,
+        constraint_name: str,
+        *elements: Any,
+        **kw: Any,
+    ) -> Optional[Table]:
+        """Issue a "create exclude constraint" instruction using the
+        current batch migration context.
+
+        .. note::  This method is Postgresql specific, and additionally
+           requires at least SQLAlchemy 1.0.
+
+        .. seealso::
+
+            :meth:`.Operations.create_exclude_constraint`
+
+        """
+        kw["schema"] = operations.impl.schema
+        op = cls(constraint_name, operations.impl.table_name, elements, **kw)
+        return operations.invoke(op)
+
+
+@render.renderers.dispatch_for(CreateExcludeConstraintOp)
+def _add_exclude_constraint(
+    autogen_context: AutogenContext, op: CreateExcludeConstraintOp
+) -> str:
+    return _exclude_constraint(op.to_constraint(), autogen_context, alter=True)
+
+
+@render._constraint_renderers.dispatch_for(ExcludeConstraint)
+def _render_inline_exclude_constraint(
+    constraint: ExcludeConstraint,
+    autogen_context: AutogenContext,
+    namespace_metadata: MetaData,
+) -> str:
+    rendered = render._user_defined_render(
+        "exclude", constraint, autogen_context
+    )
+    if rendered is not False:
+        return rendered
+
+    return _exclude_constraint(constraint, autogen_context, False)
+
+
+def _postgresql_autogenerate_prefix(autogen_context: AutogenContext) -> str:
+    imports = autogen_context.imports
+    if imports is not None:
+        imports.add("from sqlalchemy.dialects import postgresql")
+    return "postgresql."
+
+
+def _exclude_constraint(
+    constraint: ExcludeConstraint,
+    autogen_context: AutogenContext,
+    alter: bool,
+) -> str:
+    opts: List[Tuple[str, Union[quoted_name, str, _f_name, None]]] = []
+
+    has_batch = autogen_context._has_batch
+
+    if constraint.deferrable:
+        opts.append(("deferrable", str(constraint.deferrable)))
+    if constraint.initially:
+        opts.append(("initially", str(constraint.initially)))
+    if constraint.using:
+        opts.append(("using", str(constraint.using)))
+    if not has_batch and alter and constraint.table.schema:
+        opts.append(("schema", render._ident(constraint.table.schema)))
+    if not alter and constraint.name:
+        opts.append(
+            ("name", render._render_gen_name(autogen_context, constraint.name))
+        )
+
+    def do_expr_where_opts():
+        args = [
+            "(%s, %r)"
+            % (
+                _render_potential_column(
+                    sqltext,  # type:ignore[arg-type]
+                    autogen_context,
+                ),
+                opstring,
+            )
+            for sqltext, name, opstring in constraint._render_exprs
+        ]
+        if constraint.where is not None:
+            args.append(
+                "where=%s"
+                % render._render_potential_expr(
+                    constraint.where, autogen_context
+                )
+            )
+        args.extend(["%s=%r" % (k, v) for k, v in opts])
+        return args
+
+    if alter:
+        args = [
+            repr(render._render_gen_name(autogen_context, constraint.name))
+        ]
+        if not has_batch:
+            args += [repr(render._ident(constraint.table.name))]
+        args.extend(do_expr_where_opts())
+        return "%(prefix)screate_exclude_constraint(%(args)s)" % {
+            "prefix": render._alembic_autogenerate_prefix(autogen_context),
+            "args": ", ".join(args),
+        }
+    else:
+        args = do_expr_where_opts()
+        return "%(prefix)sExcludeConstraint(%(args)s)" % {
+            "prefix": _postgresql_autogenerate_prefix(autogen_context),
+            "args": ", ".join(args),
+        }
+
+
+def _render_potential_column(
+    value: Union[
+        ColumnClause[Any], Column[Any], TextClause, FunctionElement[Any]
+    ],
+    autogen_context: AutogenContext,
+) -> str:
+    if isinstance(value, ColumnClause):
+        if value.is_literal:
+            # like literal_column("int8range(from, to)") in ExcludeConstraint
+            template = "%(prefix)sliteral_column(%(name)r)"
+        else:
+            template = "%(prefix)scolumn(%(name)r)"
+
+        return template % {
+            "prefix": render._sqlalchemy_autogenerate_prefix(autogen_context),
+            "name": value.name,
+        }
+    else:
+        return render._render_potential_expr(
+            value,
+            autogen_context,
+            wrap_in_text=isinstance(value, (TextClause, FunctionElement)),
+        )

.venv2/Lib/site-packages/alembic/ddl/sqlite.py

@@ -0,0 +1,225 @@
+# mypy: allow-untyped-defs, allow-incomplete-defs, allow-untyped-calls
+# mypy: no-warn-return-any, allow-any-generics
+
+from __future__ import annotations
+
+import re
+from typing import Any
+from typing import Dict
+from typing import Optional
+from typing import TYPE_CHECKING
+from typing import Union
+
+from sqlalchemy import cast
+from sqlalchemy import JSON
+from sqlalchemy import schema
+from sqlalchemy import sql
+
+from .base import alter_table
+from .base import format_table_name
+from .base import RenameTable
+from .impl import DefaultImpl
+from .. import util
+from ..util.sqla_compat import compiles
+
+if TYPE_CHECKING:
+    from sqlalchemy.engine.reflection import Inspector
+    from sqlalchemy.sql.compiler import DDLCompiler
+    from sqlalchemy.sql.elements import Cast
+    from sqlalchemy.sql.elements import ClauseElement
+    from sqlalchemy.sql.schema import Column
+    from sqlalchemy.sql.schema import Constraint
+    from sqlalchemy.sql.schema import Table
+    from sqlalchemy.sql.type_api import TypeEngine
+
+    from ..operations.batch import BatchOperationsImpl
+
+
+class SQLiteImpl(DefaultImpl):
+    __dialect__ = "sqlite"
+
+    transactional_ddl = False
+    """SQLite supports transactional DDL, but pysqlite does not:
+    see: http://bugs.python.org/issue10740
+    """
+
+    def requires_recreate_in_batch(
+        self, batch_op: BatchOperationsImpl
+    ) -> bool:
+        """Return True if the given :class:`.BatchOperationsImpl`
+        would need the table to be recreated and copied in order to
+        proceed.
+
+        Normally, only returns True on SQLite when operations other
+        than add_column are present.
+
+        """
+        for op in batch_op.batch:
+            if op[0] == "add_column":
+                col = op[1][1]
+                if isinstance(
+                    col.server_default, schema.DefaultClause
+                ) and isinstance(col.server_default.arg, sql.ClauseElement):
+                    return True
+                elif (
+                    isinstance(col.server_default, util.sqla_compat.Computed)
+                    and col.server_default.persisted
+                ):
+                    return True
+            elif op[0] not in ("create_index", "drop_index"):
+                return True
+        else:
+            return False
+
+    def add_constraint(self, const: Constraint):
+        # attempt to distinguish between an
+        # auto-gen constraint and an explicit one
+        if const._create_rule is None:
+            raise NotImplementedError(
+                "No support for ALTER of constraints in SQLite dialect. "
+                "Please refer to the batch mode feature which allows for "
+                "SQLite migrations using a copy-and-move strategy."
+            )
+        elif const._create_rule(self):
+            util.warn(
+                "Skipping unsupported ALTER for "
+                "creation of implicit constraint. "
+                "Please refer to the batch mode feature which allows for "
+                "SQLite migrations using a copy-and-move strategy."
+            )
+
+    def drop_constraint(self, const: Constraint):
+        if const._create_rule is None:
+            raise NotImplementedError(
+                "No support for ALTER of constraints in SQLite dialect. "
+                "Please refer to the batch mode feature which allows for "
+                "SQLite migrations using a copy-and-move strategy."
+            )
+
+    def compare_server_default(
+        self,
+        inspector_column: Column[Any],
+        metadata_column: Column[Any],
+        rendered_metadata_default: Optional[str],
+        rendered_inspector_default: Optional[str],
+    ) -> bool:
+        if rendered_metadata_default is not None:
+            rendered_metadata_default = re.sub(
+                r"^\((.+)\)$", r"\1", rendered_metadata_default
+            )
+
+            rendered_metadata_default = re.sub(
+                r"^\"?'(.+)'\"?$", r"\1", rendered_metadata_default
+            )
+
+        if rendered_inspector_default is not None:
+            rendered_inspector_default = re.sub(
+                r"^\((.+)\)$", r"\1", rendered_inspector_default
+            )
+
+            rendered_inspector_default = re.sub(
+                r"^\"?'(.+)'\"?$", r"\1", rendered_inspector_default
+            )
+
+        return rendered_inspector_default != rendered_metadata_default
+
+    def _guess_if_default_is_unparenthesized_sql_expr(
+        self, expr: Optional[str]
+    ) -> bool:
+        """Determine if a server default is a SQL expression or a constant.
+
+        There are too many assertions that expect server defaults to round-trip
+        identically without parenthesis added so we will add parens only in
+        very specific cases.
+
+        """
+        if not expr:
+            return False
+        elif re.match(r"^[0-9\.]$", expr):
+            return False
+        elif re.match(r"^'.+'$", expr):
+            return False
+        elif re.match(r"^\(.+\)$", expr):
+            return False
+        else:
+            return True
+
+    def autogen_column_reflect(
+        self,
+        inspector: Inspector,
+        table: Table,
+        column_info: Dict[str, Any],
+    ) -> None:
+        # SQLite expression defaults require parenthesis when sent
+        # as DDL
+        if self._guess_if_default_is_unparenthesized_sql_expr(
+            column_info.get("default", None)
+        ):
+            column_info["default"] = "(%s)" % (column_info["default"],)
+
+    def render_ddl_sql_expr(
+        self, expr: ClauseElement, is_server_default: bool = False, **kw
+    ) -> str:
+        # SQLite expression defaults require parenthesis when sent
+        # as DDL
+        str_expr = super().render_ddl_sql_expr(
+            expr, is_server_default=is_server_default, **kw
+        )
+
+        if (
+            is_server_default
+            and self._guess_if_default_is_unparenthesized_sql_expr(str_expr)
+        ):
+            str_expr = "(%s)" % (str_expr,)
+        return str_expr
+
+    def cast_for_batch_migrate(
+        self,
+        existing: Column[Any],
+        existing_transfer: Dict[str, Union[TypeEngine, Cast]],
+        new_type: TypeEngine,
+    ) -> None:
+        if (
+            existing.type._type_affinity is not new_type._type_affinity
+            and not isinstance(new_type, JSON)
+        ):
+            existing_transfer["expr"] = cast(
+                existing_transfer["expr"], new_type
+            )
+
+    def correct_for_autogen_constraints(
+        self,
+        conn_unique_constraints,
+        conn_indexes,
+        metadata_unique_constraints,
+        metadata_indexes,
+    ):
+        self._skip_functional_indexes(metadata_indexes, conn_indexes)
+
+
+@compiles(RenameTable, "sqlite")
+def visit_rename_table(
+    element: RenameTable, compiler: DDLCompiler, **kw
+) -> str:
+    return "%s RENAME TO %s" % (
+        alter_table(compiler, element.table_name, element.schema),
+        format_table_name(compiler, element.new_table_name, None),
+    )
+
+
+# @compiles(AddColumn, 'sqlite')
+# def visit_add_column(element, compiler, **kw):
+#    return "%s %s" % (
+#        alter_table(compiler, element.table_name, element.schema),
+#        add_column(compiler, element.column, **kw)
+#    )
+
+
+# def add_column(compiler, column, **kw):
+#    text = "ADD COLUMN %s" % compiler.get_column_specification(column, **kw)
+# need to modify SQLAlchemy so that the CHECK associated with a Boolean
+# or Enum gets placed as part of the column constraints, not the Table
+# see ticket 98
+#    for const in column.constraints:
+#        text += compiler.process(AddConstraint(const))
+#    return text

.venv2/Lib/site-packages/alembic/environment.py

@@ -0,0 +1 @@
+from .runtime.environment import *  # noqa

.venv2/Lib/site-packages/alembic/migration.py

@@ -0,0 +1 @@
+from .runtime.migration import *  # noqa

.venv2/Lib/site-packages/alembic/op.py

@@ -0,0 +1,5 @@
+from .operations.base import Operations
+
+# create proxy functions for
+# each method on the Operations class.
+Operations.create_module_class_proxy(globals(), locals())

.venv2/Lib/site-packages/alembic/operations/__init__.py

@@ -0,0 +1,15 @@
+from . import toimpl
+from .base import AbstractOperations
+from .base import BatchOperations
+from .base import Operations
+from .ops import MigrateOperation
+from .ops import MigrationScript
+
+
+__all__ = [
+    "AbstractOperations",
+    "Operations",
+    "BatchOperations",
+    "MigrateOperation",
+    "MigrationScript",
+]

.venv2/Lib/site-packages/alembic/operations/batch.py

@@ -0,0 +1,717 @@
+# mypy: allow-untyped-defs, allow-incomplete-defs, allow-untyped-calls
+# mypy: no-warn-return-any, allow-any-generics
+
+from __future__ import annotations
+
+from typing import Any
+from typing import Dict
+from typing import List
+from typing import Optional
+from typing import Tuple
+from typing import TYPE_CHECKING
+from typing import Union
+
+from sqlalchemy import CheckConstraint
+from sqlalchemy import Column
+from sqlalchemy import ForeignKeyConstraint
+from sqlalchemy import Index
+from sqlalchemy import MetaData
+from sqlalchemy import PrimaryKeyConstraint
+from sqlalchemy import schema as sql_schema
+from sqlalchemy import Table
+from sqlalchemy import types as sqltypes
+from sqlalchemy.sql.schema import SchemaEventTarget
+from sqlalchemy.util import OrderedDict
+from sqlalchemy.util import topological
+
+from ..util import exc
+from ..util.sqla_compat import _columns_for_constraint
+from ..util.sqla_compat import _copy
+from ..util.sqla_compat import _copy_expression
+from ..util.sqla_compat import _ensure_scope_for_ddl
+from ..util.sqla_compat import _fk_is_self_referential
+from ..util.sqla_compat import _idx_table_bound_expressions
+from ..util.sqla_compat import _insert_inline
+from ..util.sqla_compat import _is_type_bound
+from ..util.sqla_compat import _remove_column_from_collection
+from ..util.sqla_compat import _resolve_for_variant
+from ..util.sqla_compat import _select
+from ..util.sqla_compat import constraint_name_defined
+from ..util.sqla_compat import constraint_name_string
+
+if TYPE_CHECKING:
+    from typing import Literal
+
+    from sqlalchemy.engine import Dialect
+    from sqlalchemy.sql.elements import ColumnClause
+    from sqlalchemy.sql.elements import quoted_name
+    from sqlalchemy.sql.functions import Function
+    from sqlalchemy.sql.schema import Constraint
+    from sqlalchemy.sql.type_api import TypeEngine
+
+    from ..ddl.impl import DefaultImpl
+
+
+class BatchOperationsImpl:
+    def __init__(
+        self,
+        operations,
+        table_name,
+        schema,
+        recreate,
+        copy_from,
+        table_args,
+        table_kwargs,
+        reflect_args,
+        reflect_kwargs,
+        naming_convention,
+        partial_reordering,
+    ):
+        self.operations = operations
+        self.table_name = table_name
+        self.schema = schema
+        if recreate not in ("auto", "always", "never"):
+            raise ValueError(
+                "recreate may be one of 'auto', 'always', or 'never'."
+            )
+        self.recreate = recreate
+        self.copy_from = copy_from
+        self.table_args = table_args
+        self.table_kwargs = dict(table_kwargs)
+        self.reflect_args = reflect_args
+        self.reflect_kwargs = dict(reflect_kwargs)
+        self.reflect_kwargs.setdefault(
+            "listeners", list(self.reflect_kwargs.get("listeners", ()))
+        )
+        self.reflect_kwargs["listeners"].append(
+            ("column_reflect", operations.impl.autogen_column_reflect)
+        )
+        self.naming_convention = naming_convention
+        self.partial_reordering = partial_reordering
+        self.batch = []
+
+    @property
+    def dialect(self) -> Dialect:
+        return self.operations.impl.dialect
+
+    @property
+    def impl(self) -> DefaultImpl:
+        return self.operations.impl
+
+    def _should_recreate(self) -> bool:
+        if self.recreate == "auto":
+            return self.operations.impl.requires_recreate_in_batch(self)
+        elif self.recreate == "always":
+            return True
+        else:
+            return False
+
+    def flush(self) -> None:
+        should_recreate = self._should_recreate()
+
+        with _ensure_scope_for_ddl(self.impl.connection):
+            if not should_recreate:
+                for opname, arg, kw in self.batch:
+                    fn = getattr(self.operations.impl, opname)
+                    fn(*arg, **kw)
+            else:
+                if self.naming_convention:
+                    m1 = MetaData(naming_convention=self.naming_convention)
+                else:
+                    m1 = MetaData()
+
+                if self.copy_from is not None:
+                    existing_table = self.copy_from
+                    reflected = False
+                else:
+                    if self.operations.migration_context.as_sql:
+                        raise exc.CommandError(
+                            f"This operation cannot proceed in --sql mode; "
+                            f"batch mode with dialect "
+                            f"{self.operations.migration_context.dialect.name} "  # noqa: E501
+                            f"requires a live database connection with which "
+                            f'to reflect the table "{self.table_name}". '
+                            f"To generate a batch SQL migration script using "
+                            "table "
+                            '"move and copy", a complete Table object '
+                            f'should be passed to the "copy_from" argument '
+                            "of the batch_alter_table() method so that table "
+                            "reflection can be skipped."
+                        )
+
+                    existing_table = Table(
+                        self.table_name,
+                        m1,
+                        schema=self.schema,
+                        autoload_with=self.operations.get_bind(),
+                        *self.reflect_args,
+                        **self.reflect_kwargs,
+                    )
+                    reflected = True
+
+                batch_impl = ApplyBatchImpl(
+                    self.impl,
+                    existing_table,
+                    self.table_args,
+                    self.table_kwargs,
+                    reflected,
+                    partial_reordering=self.partial_reordering,
+                )
+                for opname, arg, kw in self.batch:
+                    fn = getattr(batch_impl, opname)
+                    fn(*arg, **kw)
+
+                batch_impl._create(self.impl)
+
+    def alter_column(self, *arg, **kw) -> None:
+        self.batch.append(("alter_column", arg, kw))
+
+    def add_column(self, *arg, **kw) -> None:
+        if (
+            "insert_before" in kw or "insert_after" in kw
+        ) and not self._should_recreate():
+            raise exc.CommandError(
+                "Can't specify insert_before or insert_after when using "
+                "ALTER; please specify recreate='always'"
+            )
+        self.batch.append(("add_column", arg, kw))
+
+    def drop_column(self, *arg, **kw) -> None:
+        self.batch.append(("drop_column", arg, kw))
+
+    def add_constraint(self, const: Constraint) -> None:
+        self.batch.append(("add_constraint", (const,), {}))
+
+    def drop_constraint(self, const: Constraint) -> None:
+        self.batch.append(("drop_constraint", (const,), {}))
+
+    def rename_table(self, *arg, **kw):
+        self.batch.append(("rename_table", arg, kw))
+
+    def create_index(self, idx: Index, **kw: Any) -> None:
+        self.batch.append(("create_index", (idx,), kw))
+
+    def drop_index(self, idx: Index, **kw: Any) -> None:
+        self.batch.append(("drop_index", (idx,), kw))
+
+    def create_table_comment(self, table):
+        self.batch.append(("create_table_comment", (table,), {}))
+
+    def drop_table_comment(self, table):
+        self.batch.append(("drop_table_comment", (table,), {}))
+
+    def create_table(self, table):
+        raise NotImplementedError("Can't create table in batch mode")
+
+    def drop_table(self, table):
+        raise NotImplementedError("Can't drop table in batch mode")
+
+    def create_column_comment(self, column):
+        self.batch.append(("create_column_comment", (column,), {}))
+
+
+class ApplyBatchImpl:
+    def __init__(
+        self,
+        impl: DefaultImpl,
+        table: Table,
+        table_args: tuple,
+        table_kwargs: Dict[str, Any],
+        reflected: bool,
+        partial_reordering: tuple = (),
+    ) -> None:
+        self.impl = impl
+        self.table = table  # this is a Table object
+        self.table_args = table_args
+        self.table_kwargs = table_kwargs
+        self.temp_table_name = self._calc_temp_name(table.name)
+        self.new_table: Optional[Table] = None
+
+        self.partial_reordering = partial_reordering  # tuple of tuples
+        self.add_col_ordering: Tuple[
+            Tuple[str, str], ...
+        ] = ()  # tuple of tuples
+
+        self.column_transfers = OrderedDict(
+            (c.name, {"expr": c}) for c in self.table.c
+        )
+        self.existing_ordering = list(self.column_transfers)
+
+        self.reflected = reflected
+        self._grab_table_elements()
+
+    @classmethod
+    def _calc_temp_name(cls, tablename: Union[quoted_name, str]) -> str:
+        return ("_alembic_tmp_%s" % tablename)[0:50]
+
+    def _grab_table_elements(self) -> None:
+        schema = self.table.schema
+        self.columns: Dict[str, Column[Any]] = OrderedDict()
+        for c in self.table.c:
+            c_copy = _copy(c, schema=schema)
+            c_copy.unique = c_copy.index = False
+            # ensure that the type object was copied,
+            # as we may need to modify it in-place
+            if isinstance(c.type, SchemaEventTarget):
+                assert c_copy.type is not c.type
+            self.columns[c.name] = c_copy
+        self.named_constraints: Dict[str, Constraint] = {}
+        self.unnamed_constraints = []
+        self.col_named_constraints = {}
+        self.indexes: Dict[str, Index] = {}
+        self.new_indexes: Dict[str, Index] = {}
+
+        for const in self.table.constraints:
+            if _is_type_bound(const):
+                continue
+            elif (
+                self.reflected
+                and isinstance(const, CheckConstraint)
+                and not const.name
+            ):
+                # TODO: we are skipping unnamed reflected CheckConstraint
+                # because
+                # we have no way to determine _is_type_bound() for these.
+                pass
+            elif constraint_name_string(const.name):
+                self.named_constraints[const.name] = const
+            else:
+                self.unnamed_constraints.append(const)
+
+        if not self.reflected:
+            for col in self.table.c:
+                for const in col.constraints:
+                    if const.name:
+                        self.col_named_constraints[const.name] = (col, const)
+
+        for idx in self.table.indexes:
+            self.indexes[idx.name] = idx  # type: ignore[index]
+
+        for k in self.table.kwargs:
+            self.table_kwargs.setdefault(k, self.table.kwargs[k])
+
+    def _adjust_self_columns_for_partial_reordering(self) -> None:
+        pairs = set()
+
+        col_by_idx = list(self.columns)
+
+        if self.partial_reordering:
+            for tuple_ in self.partial_reordering:
+                for index, elem in enumerate(tuple_):
+                    if index > 0:
+                        pairs.add((tuple_[index - 1], elem))
+        else:
+            for index, elem in enumerate(self.existing_ordering):
+                if index > 0:
+                    pairs.add((col_by_idx[index - 1], elem))
+
+        pairs.update(self.add_col_ordering)
+
+        # this can happen if some columns were dropped and not removed
+        # from existing_ordering.  this should be prevented already, but
+        # conservatively making sure this didn't happen
+        pairs_list = [p for p in pairs if p[0] != p[1]]
+
+        sorted_ = list(
+            topological.sort(pairs_list, col_by_idx, deterministic_order=True)
+        )
+        self.columns = OrderedDict((k, self.columns[k]) for k in sorted_)
+        self.column_transfers = OrderedDict(
+            (k, self.column_transfers[k]) for k in sorted_
+        )
+
+    def _transfer_elements_to_new_table(self) -> None:
+        assert self.new_table is None, "Can only create new table once"
+
+        m = MetaData()
+        schema = self.table.schema
+
+        if self.partial_reordering or self.add_col_ordering:
+            self._adjust_self_columns_for_partial_reordering()
+
+        self.new_table = new_table = Table(
+            self.temp_table_name,
+            m,
+            *(list(self.columns.values()) + list(self.table_args)),
+            schema=schema,
+            **self.table_kwargs,
+        )
+
+        for const in (
+            list(self.named_constraints.values()) + self.unnamed_constraints
+        ):
+            const_columns = {c.key for c in _columns_for_constraint(const)}
+
+            if not const_columns.issubset(self.column_transfers):
+                continue
+
+            const_copy: Constraint
+            if isinstance(const, ForeignKeyConstraint):
+                if _fk_is_self_referential(const):
+                    # for self-referential constraint, refer to the
+                    # *original* table name, and not _alembic_batch_temp.
+                    # This is consistent with how we're handling
+                    # FK constraints from other tables; we assume SQLite
+                    # no foreign keys just keeps the names unchanged, so
+                    # when we rename back, they match again.
+                    const_copy = _copy(
+                        const, schema=schema, target_table=self.table
+                    )
+                else:
+                    # "target_table" for ForeignKeyConstraint.copy() is
+                    # only used if the FK is detected as being
+                    # self-referential, which we are handling above.
+                    const_copy = _copy(const, schema=schema)
+            else:
+                const_copy = _copy(
+                    const, schema=schema, target_table=new_table
+                )
+            if isinstance(const, ForeignKeyConstraint):
+                self._setup_referent(m, const)
+            new_table.append_constraint(const_copy)
+
+    def _gather_indexes_from_both_tables(self) -> List[Index]:
+        assert self.new_table is not None
+        idx: List[Index] = []
+
+        for idx_existing in self.indexes.values():
+            # this is a lift-and-move from Table.to_metadata
+
+            if idx_existing._column_flag:
+                continue
+
+            idx_copy = Index(
+                idx_existing.name,
+                unique=idx_existing.unique,
+                *[
+                    _copy_expression(expr, self.new_table)
+                    for expr in _idx_table_bound_expressions(idx_existing)
+                ],
+                _table=self.new_table,
+                **idx_existing.kwargs,
+            )
+            idx.append(idx_copy)
+
+        for index in self.new_indexes.values():
+            idx.append(
+                Index(
+                    index.name,
+                    unique=index.unique,
+                    *[self.new_table.c[col] for col in index.columns.keys()],
+                    **index.kwargs,
+                )
+            )
+        return idx
+
+    def _setup_referent(
+        self, metadata: MetaData, constraint: ForeignKeyConstraint
+    ) -> None:
+        spec = constraint.elements[0]._get_colspec()
+        parts = spec.split(".")
+        tname = parts[-2]
+        if len(parts) == 3:
+            referent_schema = parts[0]
+        else:
+            referent_schema = None
+
+        if tname != self.temp_table_name:
+            key = sql_schema._get_table_key(tname, referent_schema)
+
+            def colspec(elem: Any):
+                return elem._get_colspec()
+
+            if key in metadata.tables:
+                t = metadata.tables[key]
+                for elem in constraint.elements:
+                    colname = colspec(elem).split(".")[-1]
+                    if colname not in t.c:
+                        t.append_column(Column(colname, sqltypes.NULLTYPE))
+            else:
+                Table(
+                    tname,
+                    metadata,
+                    *[
+                        Column(n, sqltypes.NULLTYPE)
+                        for n in [
+                            colspec(elem).split(".")[-1]
+                            for elem in constraint.elements
+                        ]
+                    ],
+                    schema=referent_schema,
+                )
+
+    def _create(self, op_impl: DefaultImpl) -> None:
+        self._transfer_elements_to_new_table()
+
+        op_impl.prep_table_for_batch(self, self.table)
+        assert self.new_table is not None
+        op_impl.create_table(self.new_table)
+
+        try:
+            op_impl._exec(
+                _insert_inline(self.new_table).from_select(
+                    list(
+                        k
+                        for k, transfer in self.column_transfers.items()
+                        if "expr" in transfer
+                    ),
+                    _select(
+                        *[
+                            transfer["expr"]
+                            for transfer in self.column_transfers.values()
+                            if "expr" in transfer
+                        ]
+                    ),
+                )
+            )
+            op_impl.drop_table(self.table)
+        except:
+            op_impl.drop_table(self.new_table)
+            raise
+        else:
+            op_impl.rename_table(
+                self.temp_table_name, self.table.name, schema=self.table.schema
+            )
+            self.new_table.name = self.table.name
+            try:
+                for idx in self._gather_indexes_from_both_tables():
+                    op_impl.create_index(idx)
+            finally:
+                self.new_table.name = self.temp_table_name
+
+    def alter_column(
+        self,
+        table_name: str,
+        column_name: str,
+        nullable: Optional[bool] = None,
+        server_default: Optional[Union[Function[Any], str, bool]] = False,
+        name: Optional[str] = None,
+        type_: Optional[TypeEngine] = None,
+        autoincrement: Optional[Union[bool, Literal["auto"]]] = None,
+        comment: Union[str, Literal[False]] = False,
+        **kw,
+    ) -> None:
+        existing = self.columns[column_name]
+        existing_transfer: Dict[str, Any] = self.column_transfers[column_name]
+        if name is not None and name != column_name:
+            # note that we don't change '.key' - we keep referring
+            # to the renamed column by its old key in _create().  neat!
+            existing.name = name
+            existing_transfer["name"] = name
+
+            existing_type = kw.get("existing_type", None)
+            if existing_type:
+                resolved_existing_type = _resolve_for_variant(
+                    kw["existing_type"], self.impl.dialect
+                )
+
+                # pop named constraints for Boolean/Enum for rename
+                if (
+                    isinstance(resolved_existing_type, SchemaEventTarget)
+                    and resolved_existing_type.name  # type:ignore[attr-defined]  # noqa E501
+                ):
+                    self.named_constraints.pop(
+                        resolved_existing_type.name,  # type:ignore[attr-defined]  # noqa E501
+                        None,
+                    )
+
+        if type_ is not None:
+            type_ = sqltypes.to_instance(type_)
+            # old type is being discarded so turn off eventing
+            # rules. Alternatively we can
+            # erase the events set up by this type, but this is simpler.
+            # we also ignore the drop_constraint that will come here from
+            # Operations.implementation_for(alter_column)
+
+            if isinstance(existing.type, SchemaEventTarget):
+                existing.type._create_events = (  # type:ignore[attr-defined]
+                    existing.type.create_constraint  # type:ignore[attr-defined] # noqa
+                ) = False
+
+            self.impl.cast_for_batch_migrate(
+                existing, existing_transfer, type_
+            )
+
+            existing.type = type_
+
+            # we *dont* however set events for the new type, because
+            # alter_column is invoked from
+            # Operations.implementation_for(alter_column) which already
+            # will emit an add_constraint()
+
+        if nullable is not None:
+            existing.nullable = nullable
+        if server_default is not False:
+            if server_default is None:
+                existing.server_default = None
+            else:
+                sql_schema.DefaultClause(
+                    server_default  # type: ignore[arg-type]
+                )._set_parent(existing)
+        if autoincrement is not None:
+            existing.autoincrement = bool(autoincrement)
+
+        if comment is not False:
+            existing.comment = comment
+
+    def _setup_dependencies_for_add_column(
+        self,
+        colname: str,
+        insert_before: Optional[str],
+        insert_after: Optional[str],
+    ) -> None:
+        index_cols = self.existing_ordering
+        col_indexes = {name: i for i, name in enumerate(index_cols)}
+
+        if not self.partial_reordering:
+            if insert_after:
+                if not insert_before:
+                    if insert_after in col_indexes:
+                        # insert after an existing column
+                        idx = col_indexes[insert_after] + 1
+                        if idx < len(index_cols):
+                            insert_before = index_cols[idx]
+                    else:
+                        # insert after a column that is also new
+                        insert_before = dict(self.add_col_ordering)[
+                            insert_after
+                        ]
+            if insert_before:
+                if not insert_after:
+                    if insert_before in col_indexes:
+                        # insert before an existing column
+                        idx = col_indexes[insert_before] - 1
+                        if idx >= 0:
+                            insert_after = index_cols[idx]
+                    else:
+                        # insert before a column that is also new
+                        insert_after = {
+                            b: a for a, b in self.add_col_ordering
+                        }[insert_before]
+
+        if insert_before:
+            self.add_col_ordering += ((colname, insert_before),)
+        if insert_after:
+            self.add_col_ordering += ((insert_after, colname),)
+
+        if (
+            not self.partial_reordering
+            and not insert_before
+            and not insert_after
+            and col_indexes
+        ):
+            self.add_col_ordering += ((index_cols[-1], colname),)
+
+    def add_column(
+        self,
+        table_name: str,
+        column: Column[Any],
+        insert_before: Optional[str] = None,
+        insert_after: Optional[str] = None,
+        **kw,
+    ) -> None:
+        self._setup_dependencies_for_add_column(
+            column.name, insert_before, insert_after
+        )
+        # we copy the column because operations.add_column()
+        # gives us a Column that is part of a Table already.
+        self.columns[column.name] = _copy(column, schema=self.table.schema)
+        self.column_transfers[column.name] = {}
+
+    def drop_column(
+        self,
+        table_name: str,
+        column: Union[ColumnClause[Any], Column[Any]],
+        **kw,
+    ) -> None:
+        if column.name in self.table.primary_key.columns:
+            _remove_column_from_collection(
+                self.table.primary_key.columns, column
+            )
+        del self.columns[column.name]
+        del self.column_transfers[column.name]
+        self.existing_ordering.remove(column.name)
+
+        # pop named constraints for Boolean/Enum for rename
+        if (
+            "existing_type" in kw
+            and isinstance(kw["existing_type"], SchemaEventTarget)
+            and kw["existing_type"].name  # type:ignore[attr-defined]
+        ):
+            self.named_constraints.pop(
+                kw["existing_type"].name, None  # type:ignore[attr-defined]
+            )
+
+    def create_column_comment(self, column):
+        """the batch table creation function will issue create_column_comment
+        on the real "impl" as part of the create table process.
+
+        That is, the Column object will have the comment on it already,
+        so when it is received by add_column() it will be a normal part of
+        the CREATE TABLE and doesn't need an extra step here.
+
+        """
+
+    def create_table_comment(self, table):
+        """the batch table creation function will issue create_table_comment
+        on the real "impl" as part of the create table process.
+
+        """
+
+    def drop_table_comment(self, table):
+        """the batch table creation function will issue drop_table_comment
+        on the real "impl" as part of the create table process.
+
+        """
+
+    def add_constraint(self, const: Constraint) -> None:
+        if not constraint_name_defined(const.name):
+            raise ValueError("Constraint must have a name")
+        if isinstance(const, sql_schema.PrimaryKeyConstraint):
+            if self.table.primary_key in self.unnamed_constraints:
+                self.unnamed_constraints.remove(self.table.primary_key)
+
+        if constraint_name_string(const.name):
+            self.named_constraints[const.name] = const
+        else:
+            self.unnamed_constraints.append(const)
+
+    def drop_constraint(self, const: Constraint) -> None:
+        if not const.name:
+            raise ValueError("Constraint must have a name")
+        try:
+            if const.name in self.col_named_constraints:
+                col, const = self.col_named_constraints.pop(const.name)
+
+                for col_const in list(self.columns[col.name].constraints):
+                    if col_const.name == const.name:
+                        self.columns[col.name].constraints.remove(col_const)
+            elif constraint_name_string(const.name):
+                const = self.named_constraints.pop(const.name)
+            elif const in self.unnamed_constraints:
+                self.unnamed_constraints.remove(const)
+
+        except KeyError:
+            if _is_type_bound(const):
+                # type-bound constraints are only included in the new
+                # table via their type object in any case, so ignore the
+                # drop_constraint() that comes here via the
+                # Operations.implementation_for(alter_column)
+                return
+            raise ValueError("No such constraint: '%s'" % const.name)
+        else:
+            if isinstance(const, PrimaryKeyConstraint):
+                for col in const.columns:
+                    self.columns[col.name].primary_key = False
+
+    def create_index(self, idx: Index) -> None:
+        self.new_indexes[idx.name] = idx  # type: ignore[index]
+
+    def drop_index(self, idx: Index) -> None:
+        try:
+            del self.indexes[idx.name]  # type: ignore[arg-type]
+        except KeyError:
+            raise ValueError("No such index: '%s'" % idx.name)
+
+    def rename_table(self, *arg, **kw):
+        raise NotImplementedError("TODO")

.venv2/Lib/site-packages/alembic/operations/schemaobj.py

@@ -0,0 +1,288 @@
+# mypy: allow-untyped-defs, allow-incomplete-defs, allow-untyped-calls
+# mypy: no-warn-return-any, allow-any-generics
+
+from __future__ import annotations
+
+from typing import Any
+from typing import Dict
+from typing import List
+from typing import Optional
+from typing import Sequence
+from typing import Tuple
+from typing import TYPE_CHECKING
+from typing import Union
+
+from sqlalchemy import schema as sa_schema
+from sqlalchemy.sql.schema import Column
+from sqlalchemy.sql.schema import Constraint
+from sqlalchemy.sql.schema import Index
+from sqlalchemy.types import Integer
+from sqlalchemy.types import NULLTYPE
+
+from .. import util
+from ..util import sqla_compat
+
+if TYPE_CHECKING:
+    from sqlalchemy.sql.elements import ColumnElement
+    from sqlalchemy.sql.elements import TextClause
+    from sqlalchemy.sql.schema import CheckConstraint
+    from sqlalchemy.sql.schema import ForeignKey
+    from sqlalchemy.sql.schema import ForeignKeyConstraint
+    from sqlalchemy.sql.schema import MetaData
+    from sqlalchemy.sql.schema import PrimaryKeyConstraint
+    from sqlalchemy.sql.schema import Table
+    from sqlalchemy.sql.schema import UniqueConstraint
+    from sqlalchemy.sql.type_api import TypeEngine
+
+    from ..runtime.migration import MigrationContext
+
+
+class SchemaObjects:
+    def __init__(
+        self, migration_context: Optional[MigrationContext] = None
+    ) -> None:
+        self.migration_context = migration_context
+
+    def primary_key_constraint(
+        self,
+        name: Optional[sqla_compat._ConstraintNameDefined],
+        table_name: str,
+        cols: Sequence[str],
+        schema: Optional[str] = None,
+        **dialect_kw,
+    ) -> PrimaryKeyConstraint:
+        m = self.metadata()
+        columns = [sa_schema.Column(n, NULLTYPE) for n in cols]
+        t = sa_schema.Table(table_name, m, *columns, schema=schema)
+        # SQLAlchemy primary key constraint name arg is wrongly typed on
+        # the SQLAlchemy side through 2.0.5 at least
+        p = sa_schema.PrimaryKeyConstraint(
+            *[t.c[n] for n in cols], name=name, **dialect_kw  # type: ignore
+        )
+        return p
+
+    def foreign_key_constraint(
+        self,
+        name: Optional[sqla_compat._ConstraintNameDefined],
+        source: str,
+        referent: str,
+        local_cols: List[str],
+        remote_cols: List[str],
+        onupdate: Optional[str] = None,
+        ondelete: Optional[str] = None,
+        deferrable: Optional[bool] = None,
+        source_schema: Optional[str] = None,
+        referent_schema: Optional[str] = None,
+        initially: Optional[str] = None,
+        match: Optional[str] = None,
+        **dialect_kw,
+    ) -> ForeignKeyConstraint:
+        m = self.metadata()
+        if source == referent and source_schema == referent_schema:
+            t1_cols = local_cols + remote_cols
+        else:
+            t1_cols = local_cols
+            sa_schema.Table(
+                referent,
+                m,
+                *[sa_schema.Column(n, NULLTYPE) for n in remote_cols],
+                schema=referent_schema,
+            )
+
+        t1 = sa_schema.Table(
+            source,
+            m,
+            *[
+                sa_schema.Column(n, NULLTYPE)
+                for n in util.unique_list(t1_cols)
+            ],
+            schema=source_schema,
+        )
+
+        tname = (
+            "%s.%s" % (referent_schema, referent)
+            if referent_schema
+            else referent
+        )
+
+        dialect_kw["match"] = match
+
+        f = sa_schema.ForeignKeyConstraint(
+            local_cols,
+            ["%s.%s" % (tname, n) for n in remote_cols],
+            name=name,
+            onupdate=onupdate,
+            ondelete=ondelete,
+            deferrable=deferrable,
+            initially=initially,
+            **dialect_kw,
+        )
+        t1.append_constraint(f)
+
+        return f
+
+    def unique_constraint(
+        self,
+        name: Optional[sqla_compat._ConstraintNameDefined],
+        source: str,
+        local_cols: Sequence[str],
+        schema: Optional[str] = None,
+        **kw,
+    ) -> UniqueConstraint:
+        t = sa_schema.Table(
+            source,
+            self.metadata(),
+            *[sa_schema.Column(n, NULLTYPE) for n in local_cols],
+            schema=schema,
+        )
+        kw["name"] = name
+        uq = sa_schema.UniqueConstraint(*[t.c[n] for n in local_cols], **kw)
+        # TODO: need event tests to ensure the event
+        # is fired off here
+        t.append_constraint(uq)
+        return uq
+
+    def check_constraint(
+        self,
+        name: Optional[sqla_compat._ConstraintNameDefined],
+        source: str,
+        condition: Union[str, TextClause, ColumnElement[Any]],
+        schema: Optional[str] = None,
+        **kw,
+    ) -> Union[CheckConstraint]:
+        t = sa_schema.Table(
+            source,
+            self.metadata(),
+            sa_schema.Column("x", Integer),
+            schema=schema,
+        )
+        ck = sa_schema.CheckConstraint(condition, name=name, **kw)
+        t.append_constraint(ck)
+        return ck
+
+    def generic_constraint(
+        self,
+        name: Optional[sqla_compat._ConstraintNameDefined],
+        table_name: str,
+        type_: Optional[str],
+        schema: Optional[str] = None,
+        **kw,
+    ) -> Any:
+        t = self.table(table_name, schema=schema)
+        types: Dict[Optional[str], Any] = {
+            "foreignkey": lambda name: sa_schema.ForeignKeyConstraint(
+                [], [], name=name
+            ),
+            "primary": sa_schema.PrimaryKeyConstraint,
+            "unique": sa_schema.UniqueConstraint,
+            "check": lambda name: sa_schema.CheckConstraint("", name=name),
+            None: sa_schema.Constraint,
+        }
+        try:
+            const = types[type_]
+        except KeyError as ke:
+            raise TypeError(
+                "'type' can be one of %s"
+                % ", ".join(sorted(repr(x) for x in types))
+            ) from ke
+        else:
+            const = const(name=name)
+            t.append_constraint(const)
+            return const
+
+    def metadata(self) -> MetaData:
+        kw = {}
+        if (
+            self.migration_context is not None
+            and "target_metadata" in self.migration_context.opts
+        ):
+            mt = self.migration_context.opts["target_metadata"]
+            if hasattr(mt, "naming_convention"):
+                kw["naming_convention"] = mt.naming_convention
+        return sa_schema.MetaData(**kw)
+
+    def table(self, name: str, *columns, **kw) -> Table:
+        m = self.metadata()
+
+        cols = [
+            sqla_compat._copy(c) if c.table is not None else c
+            for c in columns
+            if isinstance(c, Column)
+        ]
+        # these flags have already added their UniqueConstraint /
+        # Index objects to the table, so flip them off here.
+        # SQLAlchemy tometadata() avoids this instead by preserving the
+        # flags and skipping the constraints that have _type_bound on them,
+        # but for a migration we'd rather list out the constraints
+        # explicitly.
+        _constraints_included = kw.pop("_constraints_included", False)
+        if _constraints_included:
+            for c in cols:
+                c.unique = c.index = False
+
+        t = sa_schema.Table(name, m, *cols, **kw)
+
+        constraints = [
+            sqla_compat._copy(elem, target_table=t)
+            if getattr(elem, "parent", None) is not t
+            and getattr(elem, "parent", None) is not None
+            else elem
+            for elem in columns
+            if isinstance(elem, (Constraint, Index))
+        ]
+
+        for const in constraints:
+            t.append_constraint(const)
+
+        for f in t.foreign_keys:
+            self._ensure_table_for_fk(m, f)
+        return t
+
+    def column(self, name: str, type_: TypeEngine, **kw) -> Column:
+        return sa_schema.Column(name, type_, **kw)
+
+    def index(
+        self,
+        name: Optional[str],
+        tablename: Optional[str],
+        columns: Sequence[Union[str, TextClause, ColumnElement[Any]]],
+        schema: Optional[str] = None,
+        **kw,
+    ) -> Index:
+        t = sa_schema.Table(
+            tablename or "no_table",
+            self.metadata(),
+            schema=schema,
+        )
+        kw["_table"] = t
+        idx = sa_schema.Index(
+            name,
+            *[util.sqla_compat._textual_index_column(t, n) for n in columns],
+            **kw,
+        )
+        return idx
+
+    def _parse_table_key(self, table_key: str) -> Tuple[Optional[str], str]:
+        if "." in table_key:
+            tokens = table_key.split(".")
+            sname: Optional[str] = ".".join(tokens[0:-1])
+            tname = tokens[-1]
+        else:
+            tname = table_key
+            sname = None
+        return (sname, tname)
+
+    def _ensure_table_for_fk(self, metadata: MetaData, fk: ForeignKey) -> None:
+        """create a placeholder Table object for the referent of a
+        ForeignKey.
+
+        """
+        if isinstance(fk._colspec, str):
+            table_key, cname = fk._colspec.rsplit(".", 1)
+            sname, tname = self._parse_table_key(table_key)
+            if table_key not in metadata.tables:
+                rel_t = sa_schema.Table(tname, metadata, schema=sname)
+            else:
+                rel_t = metadata.tables[table_key]
+            if cname not in rel_t.c:
+                rel_t.append_column(sa_schema.Column(cname, NULLTYPE))

.venv2/Lib/site-packages/alembic/operations/toimpl.py

@@ -0,0 +1,226 @@
+# mypy: allow-untyped-defs, allow-incomplete-defs, allow-untyped-calls
+# mypy: no-warn-return-any, allow-any-generics
+
+from typing import TYPE_CHECKING
+
+from sqlalchemy import schema as sa_schema
+
+from . import ops
+from .base import Operations
+from ..util.sqla_compat import _copy
+from ..util.sqla_compat import sqla_14
+
+if TYPE_CHECKING:
+    from sqlalchemy.sql.schema import Table
+
+
+@Operations.implementation_for(ops.AlterColumnOp)
+def alter_column(
+    operations: "Operations", operation: "ops.AlterColumnOp"
+) -> None:
+    compiler = operations.impl.dialect.statement_compiler(
+        operations.impl.dialect, None
+    )
+
+    existing_type = operation.existing_type
+    existing_nullable = operation.existing_nullable
+    existing_server_default = operation.existing_server_default
+    type_ = operation.modify_type
+    column_name = operation.column_name
+    table_name = operation.table_name
+    schema = operation.schema
+    server_default = operation.modify_server_default
+    new_column_name = operation.modify_name
+    nullable = operation.modify_nullable
+    comment = operation.modify_comment
+    existing_comment = operation.existing_comment
+
+    def _count_constraint(constraint):
+        return not isinstance(constraint, sa_schema.PrimaryKeyConstraint) and (
+            not constraint._create_rule or constraint._create_rule(compiler)
+        )
+
+    if existing_type and type_:
+        t = operations.schema_obj.table(
+            table_name,
+            sa_schema.Column(column_name, existing_type),
+            schema=schema,
+        )
+        for constraint in t.constraints:
+            if _count_constraint(constraint):
+                operations.impl.drop_constraint(constraint)
+
+    operations.impl.alter_column(
+        table_name,
+        column_name,
+        nullable=nullable,
+        server_default=server_default,
+        name=new_column_name,
+        type_=type_,
+        schema=schema,
+        existing_type=existing_type,
+        existing_server_default=existing_server_default,
+        existing_nullable=existing_nullable,
+        comment=comment,
+        existing_comment=existing_comment,
+        **operation.kw,
+    )
+
+    if type_:
+        t = operations.schema_obj.table(
+            table_name,
+            operations.schema_obj.column(column_name, type_),
+            schema=schema,
+        )
+        for constraint in t.constraints:
+            if _count_constraint(constraint):
+                operations.impl.add_constraint(constraint)
+
+
+@Operations.implementation_for(ops.DropTableOp)
+def drop_table(operations: "Operations", operation: "ops.DropTableOp") -> None:
+    operations.impl.drop_table(
+        operation.to_table(operations.migration_context)
+    )
+
+
+@Operations.implementation_for(ops.DropColumnOp)
+def drop_column(
+    operations: "Operations", operation: "ops.DropColumnOp"
+) -> None:
+    column = operation.to_column(operations.migration_context)
+    operations.impl.drop_column(
+        operation.table_name, column, schema=operation.schema, **operation.kw
+    )
+
+
+@Operations.implementation_for(ops.CreateIndexOp)
+def create_index(
+    operations: "Operations", operation: "ops.CreateIndexOp"
+) -> None:
+    idx = operation.to_index(operations.migration_context)
+    kw = {}
+    if operation.if_not_exists is not None:
+        if not sqla_14:
+            raise NotImplementedError("SQLAlchemy 1.4+ required")
+
+        kw["if_not_exists"] = operation.if_not_exists
+    operations.impl.create_index(idx, **kw)
+
+
+@Operations.implementation_for(ops.DropIndexOp)
+def drop_index(operations: "Operations", operation: "ops.DropIndexOp") -> None:
+    kw = {}
+    if operation.if_exists is not None:
+        if not sqla_14:
+            raise NotImplementedError("SQLAlchemy 1.4+ required")
+
+        kw["if_exists"] = operation.if_exists
+
+    operations.impl.drop_index(
+        operation.to_index(operations.migration_context),
+        **kw,
+    )
+
+
+@Operations.implementation_for(ops.CreateTableOp)
+def create_table(
+    operations: "Operations", operation: "ops.CreateTableOp"
+) -> "Table":
+    table = operation.to_table(operations.migration_context)
+    operations.impl.create_table(table)
+    return table
+
+
+@Operations.implementation_for(ops.RenameTableOp)
+def rename_table(
+    operations: "Operations", operation: "ops.RenameTableOp"
+) -> None:
+    operations.impl.rename_table(
+        operation.table_name, operation.new_table_name, schema=operation.schema
+    )
+
+
+@Operations.implementation_for(ops.CreateTableCommentOp)
+def create_table_comment(
+    operations: "Operations", operation: "ops.CreateTableCommentOp"
+) -> None:
+    table = operation.to_table(operations.migration_context)
+    operations.impl.create_table_comment(table)
+
+
+@Operations.implementation_for(ops.DropTableCommentOp)
+def drop_table_comment(
+    operations: "Operations", operation: "ops.DropTableCommentOp"
+) -> None:
+    table = operation.to_table(operations.migration_context)
+    operations.impl.drop_table_comment(table)
+
+
+@Operations.implementation_for(ops.AddColumnOp)
+def add_column(operations: "Operations", operation: "ops.AddColumnOp") -> None:
+    table_name = operation.table_name
+    column = operation.column
+    schema = operation.schema
+    kw = operation.kw
+
+    if column.table is not None:
+        column = _copy(column)
+
+    t = operations.schema_obj.table(table_name, column, schema=schema)
+    operations.impl.add_column(table_name, column, schema=schema, **kw)
+
+    for constraint in t.constraints:
+        if not isinstance(constraint, sa_schema.PrimaryKeyConstraint):
+            operations.impl.add_constraint(constraint)
+    for index in t.indexes:
+        operations.impl.create_index(index)
+
+    with_comment = (
+        operations.impl.dialect.supports_comments
+        and not operations.impl.dialect.inline_comments
+    )
+    comment = column.comment
+    if comment and with_comment:
+        operations.impl.create_column_comment(column)
+
+
+@Operations.implementation_for(ops.AddConstraintOp)
+def create_constraint(
+    operations: "Operations", operation: "ops.AddConstraintOp"
+) -> None:
+    operations.impl.add_constraint(
+        operation.to_constraint(operations.migration_context)
+    )
+
+
+@Operations.implementation_for(ops.DropConstraintOp)
+def drop_constraint(
+    operations: "Operations", operation: "ops.DropConstraintOp"
+) -> None:
+    operations.impl.drop_constraint(
+        operations.schema_obj.generic_constraint(
+            operation.constraint_name,
+            operation.table_name,
+            operation.constraint_type,
+            schema=operation.schema,
+        )
+    )
+
+
+@Operations.implementation_for(ops.BulkInsertOp)
+def bulk_insert(
+    operations: "Operations", operation: "ops.BulkInsertOp"
+) -> None:
+    operations.impl.bulk_insert(  # type: ignore[union-attr]
+        operation.table, operation.rows, multiinsert=operation.multiinsert
+    )
+
+
+@Operations.implementation_for(ops.ExecuteSQLOp)
+def execute_sql(
+    operations: "Operations", operation: "ops.ExecuteSQLOp"
+) -> None:
+    operations.migration_context.impl.execute(
+        operation.sqltext, execution_options=operation.execution_options
+    )

.venv2/Lib/site-packages/alembic/script/__init__.py

@@ -0,0 +1,4 @@
+from .base import Script
+from .base import ScriptDirectory
+
+__all__ = ["ScriptDirectory", "Script"]

.venv2/Lib/site-packages/alembic/script/write_hooks.py

@@ -0,0 +1,179 @@
+# mypy: allow-untyped-defs, allow-incomplete-defs, allow-untyped-calls
+# mypy: no-warn-return-any, allow-any-generics
+
+from __future__ import annotations
+
+import shlex
+import subprocess
+import sys
+from typing import Any
+from typing import Callable
+from typing import Dict
+from typing import List
+from typing import Mapping
+from typing import Optional
+from typing import Union
+
+from .. import util
+from ..util import compat
+
+
+REVISION_SCRIPT_TOKEN = "REVISION_SCRIPT_FILENAME"
+
+_registry: dict = {}
+
+
+def register(name: str) -> Callable:
+    """A function decorator that will register that function as a write hook.
+
+    See the documentation linked below for an example.
+
+    .. seealso::
+
+        :ref:`post_write_hooks_custom`
+
+
+    """
+
+    def decorate(fn):
+        _registry[name] = fn
+        return fn
+
+    return decorate
+
+
+def _invoke(
+    name: str, revision: str, options: Mapping[str, Union[str, int]]
+) -> Any:
+    """Invokes the formatter registered for the given name.
+
+    :param name: The name of a formatter in the registry
+    :param revision: A :class:`.MigrationRevision` instance
+    :param options: A dict containing kwargs passed to the
+        specified formatter.
+    :raises: :class:`alembic.util.CommandError`
+    """
+    try:
+        hook = _registry[name]
+    except KeyError as ke:
+        raise util.CommandError(
+            f"No formatter with name '{name}' registered"
+        ) from ke
+    else:
+        return hook(revision, options)
+
+
+def _run_hooks(path: str, hook_config: Mapping[str, str]) -> None:
+    """Invoke hooks for a generated revision."""
+
+    from .base import _split_on_space_comma
+
+    names = _split_on_space_comma.split(hook_config.get("hooks", ""))
+
+    for name in names:
+        if not name:
+            continue
+        opts = {
+            key[len(name) + 1 :]: hook_config[key]
+            for key in hook_config
+            if key.startswith(name + ".")
+        }
+        opts["_hook_name"] = name
+        try:
+            type_ = opts["type"]
+        except KeyError as ke:
+            raise util.CommandError(
+                f"Key {name}.type is required for post write hook {name!r}"
+            ) from ke
+        else:
+            with util.status(
+                f"Running post write hook {name!r}", newline=True
+            ):
+                _invoke(type_, path, opts)
+
+
+def _parse_cmdline_options(cmdline_options_str: str, path: str) -> List[str]:
+    """Parse options from a string into a list.
+
+    Also substitutes the revision script token with the actual filename of
+    the revision script.
+
+    If the revision script token doesn't occur in the options string, it is
+    automatically prepended.
+    """
+    if REVISION_SCRIPT_TOKEN not in cmdline_options_str:
+        cmdline_options_str = REVISION_SCRIPT_TOKEN + " " + cmdline_options_str
+    cmdline_options_list = shlex.split(
+        cmdline_options_str, posix=compat.is_posix
+    )
+    cmdline_options_list = [
+        option.replace(REVISION_SCRIPT_TOKEN, path)
+        for option in cmdline_options_list
+    ]
+    return cmdline_options_list
+
+
+@register("console_scripts")
+def console_scripts(
+    path: str, options: dict, ignore_output: bool = False
+) -> None:
+    try:
+        entrypoint_name = options["entrypoint"]
+    except KeyError as ke:
+        raise util.CommandError(
+            f"Key {options['_hook_name']}.entrypoint is required for post "
+            f"write hook {options['_hook_name']!r}"
+        ) from ke
+    for entry in compat.importlib_metadata_get("console_scripts"):
+        if entry.name == entrypoint_name:
+            impl: Any = entry
+            break
+    else:
+        raise util.CommandError(
+            f"Could not find entrypoint console_scripts.{entrypoint_name}"
+        )
+    cwd: Optional[str] = options.get("cwd", None)
+    cmdline_options_str = options.get("options", "")
+    cmdline_options_list = _parse_cmdline_options(cmdline_options_str, path)
+
+    kw: Dict[str, Any] = {}
+    if ignore_output:
+        kw["stdout"] = kw["stderr"] = subprocess.DEVNULL
+
+    subprocess.run(
+        [
+            sys.executable,
+            "-c",
+            f"import {impl.module}; {impl.module}.{impl.attr}()",
+        ]
+        + cmdline_options_list,
+        cwd=cwd,
+        **kw,
+    )
+
+
+@register("exec")
+def exec_(path: str, options: dict, ignore_output: bool = False) -> None:
+    try:
+        executable = options["executable"]
+    except KeyError as ke:
+        raise util.CommandError(
+            f"Key {options['_hook_name']}.executable is required for post "
+            f"write hook {options['_hook_name']!r}"
+        ) from ke
+    cwd: Optional[str] = options.get("cwd", None)
+    cmdline_options_str = options.get("options", "")
+    cmdline_options_list = _parse_cmdline_options(cmdline_options_str, path)
+
+    kw: Dict[str, Any] = {}
+    if ignore_output:
+        kw["stdout"] = kw["stderr"] = subprocess.DEVNULL
+
+    subprocess.run(
+        [
+            executable,
+            *cmdline_options_list,
+        ],
+        cwd=cwd,
+        **kw,
+    )

.venv2/Lib/site-packages/alembic/templates/async/README

@@ -0,0 +1 @@
+Generic single-database configuration with an async dbapi.

.venv2/Lib/site-packages/alembic/templates/async/alembic.ini.mako

@@ -0,0 +1,114 @@
+# A generic, single database configuration.
+
+[alembic]
+# path to migration scripts
+script_location = ${script_location}
+
+# template used to generate migration file names; The default value is %%(rev)s_%%(slug)s
+# Uncomment the line below if you want the files to be prepended with date and time
+# file_template = %%(year)d_%%(month).2d_%%(day).2d_%%(hour).2d%%(minute).2d-%%(rev)s_%%(slug)s
+
+# sys.path path, will be prepended to sys.path if present.
+# defaults to the current working directory.
+prepend_sys_path = .
+
+# timezone to use when rendering the date within the migration file
+# as well as the filename.
+# If specified, requires the python>=3.9 or backports.zoneinfo library.
+# Any required deps can installed by adding `alembic[tz]` to the pip requirements
+# string value is passed to ZoneInfo()
+# leave blank for localtime
+# timezone =
+
+# max length of characters to apply to the
+# "slug" field
+# truncate_slug_length = 40
+
+# set to 'true' to run the environment during
+# the 'revision' command, regardless of autogenerate
+# revision_environment = false
+
+# set to 'true' to allow .pyc and .pyo files without
+# a source .py file to be detected as revisions in the
+# versions/ directory
+# sourceless = false
+
+# version location specification; This defaults
+# to ${script_location}/versions.  When using multiple version
+# directories, initial revisions must be specified with --version-path.
+# The path separator used here should be the separator specified by "version_path_separator" below.
+# version_locations = %(here)s/bar:%(here)s/bat:${script_location}/versions
+
+# version path separator; As mentioned above, this is the character used to split
+# version_locations. The default within new alembic.ini files is "os", which uses os.pathsep.
+# If this key is omitted entirely, it falls back to the legacy behavior of splitting on spaces and/or commas.
+# Valid values for version_path_separator are:
+#
+# version_path_separator = :
+# version_path_separator = ;
+# version_path_separator = space
+version_path_separator = os  # Use os.pathsep. Default configuration used for new projects.
+
+# set to 'true' to search source files recursively
+# in each "version_locations" directory
+# new in Alembic version 1.10
+# recursive_version_locations = false
+
+# the output encoding used when revision files
+# are written from script.py.mako
+# output_encoding = utf-8
+
+sqlalchemy.url = driver://user:pass@localhost/dbname
+
+
+[post_write_hooks]
+# post_write_hooks defines scripts or Python functions that are run
+# on newly generated revision scripts.  See the documentation for further
+# detail and examples
+
+# format using "black" - use the console_scripts runner, against the "black" entrypoint
+# hooks = black
+# black.type = console_scripts
+# black.entrypoint = black
+# black.options = -l 79 REVISION_SCRIPT_FILENAME
+
+# lint with attempts to fix using "ruff" - use the exec runner, execute a binary
+# hooks = ruff
+# ruff.type = exec
+# ruff.executable = %(here)s/.venv/bin/ruff
+# ruff.options = --fix REVISION_SCRIPT_FILENAME
+
+# Logging configuration
+[loggers]
+keys = root,sqlalchemy,alembic
+
+[handlers]
+keys = console
+
+[formatters]
+keys = generic
+
+[logger_root]
+level = WARN
+handlers = console
+qualname =
+
+[logger_sqlalchemy]
+level = WARN
+handlers =
+qualname = sqlalchemy.engine
+
+[logger_alembic]
+level = INFO
+handlers =
+qualname = alembic
+
+[handler_console]
+class = StreamHandler
+args = (sys.stderr,)
+level = NOTSET
+formatter = generic
+
+[formatter_generic]
+format = %(levelname)-5.5s [%(name)s] %(message)s
+datefmt = %H:%M:%S

.venv2/Lib/site-packages/alembic/templates/async/env.py

@@ -0,0 +1,89 @@
+import asyncio
+from logging.config import fileConfig
+
+from sqlalchemy import pool
+from sqlalchemy.engine import Connection
+from sqlalchemy.ext.asyncio import async_engine_from_config
+
+from alembic import context
+
+# this is the Alembic Config object, which provides
+# access to the values within the .ini file in use.
+config = context.config
+
+# Interpret the config file for Python logging.
+# This line sets up loggers basically.
+if config.config_file_name is not None:
+    fileConfig(config.config_file_name)
+
+# add your model's MetaData object here
+# for 'autogenerate' support
+# from myapp import mymodel
+# target_metadata = mymodel.Base.metadata
+target_metadata = None
+
+# other values from the config, defined by the needs of env.py,
+# can be acquired:
+# my_important_option = config.get_main_option("my_important_option")
+# ... etc.
+
+
+def run_migrations_offline() -> None:
+    """Run migrations in 'offline' mode.
+
+    This configures the context with just a URL
+    and not an Engine, though an Engine is acceptable
+    here as well.  By skipping the Engine creation
+    we don't even need a DBAPI to be available.
+
+    Calls to context.execute() here emit the given string to the
+    script output.
+
+    """
+    url = config.get_main_option("sqlalchemy.url")
+    context.configure(
+        url=url,
+        target_metadata=target_metadata,
+        literal_binds=True,
+        dialect_opts={"paramstyle": "named"},
+    )
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def do_run_migrations(connection: Connection) -> None:
+    context.configure(connection=connection, target_metadata=target_metadata)
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+async def run_async_migrations() -> None:
+    """In this scenario we need to create an Engine
+    and associate a connection with the context.
+
+    """
+
+    connectable = async_engine_from_config(
+        config.get_section(config.config_ini_section, {}),
+        prefix="sqlalchemy.",
+        poolclass=pool.NullPool,
+    )
+
+    async with connectable.connect() as connection:
+        await connection.run_sync(do_run_migrations)
+
+    await connectable.dispose()
+
+
+def run_migrations_online() -> None:
+    """Run migrations in 'online' mode."""
+
+    asyncio.run(run_async_migrations())
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()

.venv2/Lib/site-packages/alembic/templates/async/script.py.mako

@@ -0,0 +1,26 @@
+"""${message}
+
+Revision ID: ${up_revision}
+Revises: ${down_revision | comma,n}
+Create Date: ${create_date}
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+${imports if imports else ""}
+
+# revision identifiers, used by Alembic.
+revision: str = ${repr(up_revision)}
+down_revision: Union[str, None] = ${repr(down_revision)}
+branch_labels: Union[str, Sequence[str], None] = ${repr(branch_labels)}
+depends_on: Union[str, Sequence[str], None] = ${repr(depends_on)}
+
+
+def upgrade() -> None:
+    ${upgrades if upgrades else "pass"}
+
+
+def downgrade() -> None:
+    ${downgrades if downgrades else "pass"}

.venv2/Lib/site-packages/alembic/templates/generic/README

@@ -0,0 +1 @@
+Generic single-database configuration.

.venv2/Lib/site-packages/alembic/templates/generic/alembic.ini.mako

@@ -0,0 +1,116 @@
+# A generic, single database configuration.
+
+[alembic]
+# path to migration scripts
+script_location = ${script_location}
+
+# template used to generate migration file names; The default value is %%(rev)s_%%(slug)s
+# Uncomment the line below if you want the files to be prepended with date and time
+# see https://alembic.sqlalchemy.org/en/latest/tutorial.html#editing-the-ini-file
+# for all available tokens
+# file_template = %%(year)d_%%(month).2d_%%(day).2d_%%(hour).2d%%(minute).2d-%%(rev)s_%%(slug)s
+
+# sys.path path, will be prepended to sys.path if present.
+# defaults to the current working directory.
+prepend_sys_path = .
+
+# timezone to use when rendering the date within the migration file
+# as well as the filename.
+# If specified, requires the python>=3.9 or backports.zoneinfo library.
+# Any required deps can installed by adding `alembic[tz]` to the pip requirements
+# string value is passed to ZoneInfo()
+# leave blank for localtime
+# timezone =
+
+# max length of characters to apply to the
+# "slug" field
+# truncate_slug_length = 40
+
+# set to 'true' to run the environment during
+# the 'revision' command, regardless of autogenerate
+# revision_environment = false
+
+# set to 'true' to allow .pyc and .pyo files without
+# a source .py file to be detected as revisions in the
+# versions/ directory
+# sourceless = false
+
+# version location specification; This defaults
+# to ${script_location}/versions.  When using multiple version
+# directories, initial revisions must be specified with --version-path.
+# The path separator used here should be the separator specified by "version_path_separator" below.
+# version_locations = %(here)s/bar:%(here)s/bat:${script_location}/versions
+
+# version path separator; As mentioned above, this is the character used to split
+# version_locations. The default within new alembic.ini files is "os", which uses os.pathsep.
+# If this key is omitted entirely, it falls back to the legacy behavior of splitting on spaces and/or commas.
+# Valid values for version_path_separator are:
+#
+# version_path_separator = :
+# version_path_separator = ;
+# version_path_separator = space
+version_path_separator = os  # Use os.pathsep. Default configuration used for new projects.
+
+# set to 'true' to search source files recursively
+# in each "version_locations" directory
+# new in Alembic version 1.10
+# recursive_version_locations = false
+
+# the output encoding used when revision files
+# are written from script.py.mako
+# output_encoding = utf-8
+
+sqlalchemy.url = driver://user:pass@localhost/dbname
+
+
+[post_write_hooks]
+# post_write_hooks defines scripts or Python functions that are run
+# on newly generated revision scripts.  See the documentation for further
+# detail and examples
+
+# format using "black" - use the console_scripts runner, against the "black" entrypoint
+# hooks = black
+# black.type = console_scripts
+# black.entrypoint = black
+# black.options = -l 79 REVISION_SCRIPT_FILENAME
+
+# lint with attempts to fix using "ruff" - use the exec runner, execute a binary
+# hooks = ruff
+# ruff.type = exec
+# ruff.executable = %(here)s/.venv/bin/ruff
+# ruff.options = --fix REVISION_SCRIPT_FILENAME
+
+# Logging configuration
+[loggers]
+keys = root,sqlalchemy,alembic
+
+[handlers]
+keys = console
+
+[formatters]
+keys = generic
+
+[logger_root]
+level = WARN
+handlers = console
+qualname =
+
+[logger_sqlalchemy]
+level = WARN
+handlers =
+qualname = sqlalchemy.engine
+
+[logger_alembic]
+level = INFO
+handlers =
+qualname = alembic
+
+[handler_console]
+class = StreamHandler
+args = (sys.stderr,)
+level = NOTSET
+formatter = generic
+
+[formatter_generic]
+format = %(levelname)-5.5s [%(name)s] %(message)s
+datefmt = %H:%M:%S

.venv2/Lib/site-packages/alembic/templates/generic/env.py

@@ -0,0 +1,78 @@
+from logging.config import fileConfig
+
+from sqlalchemy import engine_from_config
+from sqlalchemy import pool
+
+from alembic import context
+
+# this is the Alembic Config object, which provides
+# access to the values within the .ini file in use.
+config = context.config
+
+# Interpret the config file for Python logging.
+# This line sets up loggers basically.
+if config.config_file_name is not None:
+    fileConfig(config.config_file_name)
+
+# add your model's MetaData object here
+# for 'autogenerate' support
+# from myapp import mymodel
+# target_metadata = mymodel.Base.metadata
+target_metadata = None
+
+# other values from the config, defined by the needs of env.py,
+# can be acquired:
+# my_important_option = config.get_main_option("my_important_option")
+# ... etc.
+
+
+def run_migrations_offline() -> None:
+    """Run migrations in 'offline' mode.
+
+    This configures the context with just a URL
+    and not an Engine, though an Engine is acceptable
+    here as well.  By skipping the Engine creation
+    we don't even need a DBAPI to be available.
+
+    Calls to context.execute() here emit the given string to the
+    script output.
+
+    """
+    url = config.get_main_option("sqlalchemy.url")
+    context.configure(
+        url=url,
+        target_metadata=target_metadata,
+        literal_binds=True,
+        dialect_opts={"paramstyle": "named"},
+    )
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def run_migrations_online() -> None:
+    """Run migrations in 'online' mode.
+
+    In this scenario we need to create an Engine
+    and associate a connection with the context.
+
+    """
+    connectable = engine_from_config(
+        config.get_section(config.config_ini_section, {}),
+        prefix="sqlalchemy.",
+        poolclass=pool.NullPool,
+    )
+
+    with connectable.connect() as connection:
+        context.configure(
+            connection=connection, target_metadata=target_metadata
+        )
+
+        with context.begin_transaction():
+            context.run_migrations()
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()

.venv2/Lib/site-packages/alembic/templates/generic/script.py.mako

@@ -0,0 +1,26 @@
+"""${message}
+
+Revision ID: ${up_revision}
+Revises: ${down_revision | comma,n}
+Create Date: ${create_date}
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+${imports if imports else ""}
+
+# revision identifiers, used by Alembic.
+revision: str = ${repr(up_revision)}
+down_revision: Union[str, None] = ${repr(down_revision)}
+branch_labels: Union[str, Sequence[str], None] = ${repr(branch_labels)}
+depends_on: Union[str, Sequence[str], None] = ${repr(depends_on)}
+
+
+def upgrade() -> None:
+    ${upgrades if upgrades else "pass"}
+
+
+def downgrade() -> None:
+    ${downgrades if downgrades else "pass"}

.venv2/Lib/site-packages/alembic/templates/multidb/README

@@ -0,0 +1,12 @@
+Rudimentary multi-database configuration.
+
+Multi-DB isn't vastly different from generic. The primary difference is that it
+will run the migrations N times (depending on how many databases you have
+configured), providing one engine name and associated context for each run.
+
+That engine name will then allow the migration to restrict what runs within it to
+just the appropriate migrations for that engine. You can see this behavior within
+the mako template.
+
+In the provided configuration, you'll need to have `databases` provided in
+alembic's config, and an `sqlalchemy.url` provided for each engine name.

.venv2/Lib/site-packages/alembic/templates/multidb/alembic.ini.mako

@@ -0,0 +1,121 @@
+# a multi-database configuration.
+
+[alembic]
+# path to migration scripts
+script_location = ${script_location}
+
+# template used to generate migration file names; The default value is %%(rev)s_%%(slug)s
+# Uncomment the line below if you want the files to be prepended with date and time
+# see https://alembic.sqlalchemy.org/en/latest/tutorial.html#editing-the-ini-file
+# for all available tokens
+# file_template = %%(year)d_%%(month).2d_%%(day).2d_%%(hour).2d%%(minute).2d-%%(rev)s_%%(slug)s
+
+# sys.path path, will be prepended to sys.path if present.
+# defaults to the current working directory.
+prepend_sys_path = .
+
+# timezone to use when rendering the date within the migration file
+# as well as the filename.
+# If specified, requires the python>=3.9 or backports.zoneinfo library.
+# Any required deps can installed by adding `alembic[tz]` to the pip requirements
+# string value is passed to ZoneInfo()
+# leave blank for localtime
+# timezone =
+
+# max length of characters to apply to the
+# "slug" field
+# truncate_slug_length = 40
+
+# set to 'true' to run the environment during
+# the 'revision' command, regardless of autogenerate
+# revision_environment = false
+
+# set to 'true' to allow .pyc and .pyo files without
+# a source .py file to be detected as revisions in the
+# versions/ directory
+# sourceless = false
+
+# version location specification; This defaults
+# to ${script_location}/versions.  When using multiple version
+# directories, initial revisions must be specified with --version-path.
+# The path separator used here should be the separator specified by "version_path_separator" below.
+# version_locations = %(here)s/bar:%(here)s/bat:${script_location}/versions
+
+# version path separator; As mentioned above, this is the character used to split
+# version_locations. The default within new alembic.ini files is "os", which uses os.pathsep.
+# If this key is omitted entirely, it falls back to the legacy behavior of splitting on spaces and/or commas.
+# Valid values for version_path_separator are:
+#
+# version_path_separator = :
+# version_path_separator = ;
+# version_path_separator = space
+version_path_separator = os  # Use os.pathsep. Default configuration used for new projects.
+
+# set to 'true' to search source files recursively
+# in each "version_locations" directory
+# new in Alembic version 1.10
+# recursive_version_locations = false
+
+# the output encoding used when revision files
+# are written from script.py.mako
+# output_encoding = utf-8
+
+databases = engine1, engine2
+
+[engine1]
+sqlalchemy.url = driver://user:pass@localhost/dbname
+
+[engine2]
+sqlalchemy.url = driver://user:pass@localhost/dbname2
+
+[post_write_hooks]
+# post_write_hooks defines scripts or Python functions that are run
+# on newly generated revision scripts.  See the documentation for further
+# detail and examples
+
+# format using "black" - use the console_scripts runner, against the "black" entrypoint
+# hooks = black
+# black.type = console_scripts
+# black.entrypoint = black
+# black.options = -l 79 REVISION_SCRIPT_FILENAME
+
+# lint with attempts to fix using "ruff" - use the exec runner, execute a binary
+# hooks = ruff
+# ruff.type = exec
+# ruff.executable = %(here)s/.venv/bin/ruff
+# ruff.options = --fix REVISION_SCRIPT_FILENAME
+
+# Logging configuration
+[loggers]
+keys = root,sqlalchemy,alembic
+
+[handlers]
+keys = console
+
+[formatters]
+keys = generic
+
+[logger_root]
+level = WARN
+handlers = console
+qualname =
+
+[logger_sqlalchemy]
+level = WARN
+handlers =
+qualname = sqlalchemy.engine
+
+[logger_alembic]
+level = INFO
+handlers =
+qualname = alembic
+
+[handler_console]
+class = StreamHandler
+args = (sys.stderr,)
+level = NOTSET
+formatter = generic
+
+[formatter_generic]
+format = %(levelname)-5.5s [%(name)s] %(message)s
+datefmt = %H:%M:%S

.venv2/Lib/site-packages/alembic/templates/multidb/env.py

@@ -0,0 +1,140 @@
+import logging
+from logging.config import fileConfig
+import re
+
+from sqlalchemy import engine_from_config
+from sqlalchemy import pool
+
+from alembic import context
+
+USE_TWOPHASE = False
+
+# this is the Alembic Config object, which provides
+# access to the values within the .ini file in use.
+config = context.config
+
+# Interpret the config file for Python logging.
+# This line sets up loggers basically.
+if config.config_file_name is not None:
+    fileConfig(config.config_file_name)
+logger = logging.getLogger("alembic.env")
+
+# gather section names referring to different
+# databases.  These are named "engine1", "engine2"
+# in the sample .ini file.
+db_names = config.get_main_option("databases", "")
+
+# add your model's MetaData objects here
+# for 'autogenerate' support.  These must be set
+# up to hold just those tables targeting a
+# particular database. table.tometadata() may be
+# helpful here in case a "copy" of
+# a MetaData is needed.
+# from myapp import mymodel
+# target_metadata = {
+#       'engine1':mymodel.metadata1,
+#       'engine2':mymodel.metadata2
+# }
+target_metadata = {}
+
+# other values from the config, defined by the needs of env.py,
+# can be acquired:
+# my_important_option = config.get_main_option("my_important_option")
+# ... etc.
+
+
+def run_migrations_offline() -> None:
+    """Run migrations in 'offline' mode.
+
+    This configures the context with just a URL
+    and not an Engine, though an Engine is acceptable
+    here as well.  By skipping the Engine creation
+    we don't even need a DBAPI to be available.
+
+    Calls to context.execute() here emit the given string to the
+    script output.
+
+    """
+    # for the --sql use case, run migrations for each URL into
+    # individual files.
+
+    engines = {}
+    for name in re.split(r",\s*", db_names):
+        engines[name] = rec = {}
+        rec["url"] = context.config.get_section_option(name, "sqlalchemy.url")
+
+    for name, rec in engines.items():
+        logger.info("Migrating database %s" % name)
+        file_ = "%s.sql" % name
+        logger.info("Writing output to %s" % file_)
+        with open(file_, "w") as buffer:
+            context.configure(
+                url=rec["url"],
+                output_buffer=buffer,
+                target_metadata=target_metadata.get(name),
+                literal_binds=True,
+                dialect_opts={"paramstyle": "named"},
+            )
+            with context.begin_transaction():
+                context.run_migrations(engine_name=name)
+
+
+def run_migrations_online() -> None:
+    """Run migrations in 'online' mode.
+
+    In this scenario we need to create an Engine
+    and associate a connection with the context.
+
+    """
+
+    # for the direct-to-DB use case, start a transaction on all
+    # engines, then run all migrations, then commit all transactions.
+
+    engines = {}
+    for name in re.split(r",\s*", db_names):
+        engines[name] = rec = {}
+        rec["engine"] = engine_from_config(
+            context.config.get_section(name, {}),
+            prefix="sqlalchemy.",
+            poolclass=pool.NullPool,
+        )
+
+    for name, rec in engines.items():
+        engine = rec["engine"]
+        rec["connection"] = conn = engine.connect()
+
+        if USE_TWOPHASE:
+            rec["transaction"] = conn.begin_twophase()
+        else:
+            rec["transaction"] = conn.begin()
+
+    try:
+        for name, rec in engines.items():
+            logger.info("Migrating database %s" % name)
+            context.configure(
+                connection=rec["connection"],
+                upgrade_token="%s_upgrades" % name,
+                downgrade_token="%s_downgrades" % name,
+                target_metadata=target_metadata.get(name),
+            )
+            context.run_migrations(engine_name=name)
+
+        if USE_TWOPHASE:
+            for rec in engines.values():
+                rec["transaction"].prepare()
+
+        for rec in engines.values():
+            rec["transaction"].commit()
+    except:
+        for rec in engines.values():
+            rec["transaction"].rollback()
+        raise
+    finally:
+        for rec in engines.values():
+            rec["connection"].close()
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()

.venv2/Lib/site-packages/alembic/templates/multidb/script.py.mako

@@ -0,0 +1,47 @@
+<%!
+import re
+
+%>"""${message}
+
+Revision ID: ${up_revision}
+Revises: ${down_revision | comma,n}
+Create Date: ${create_date}
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+${imports if imports else ""}
+
+# revision identifiers, used by Alembic.
+revision: str = ${repr(up_revision)}
+down_revision: Union[str, None] = ${repr(down_revision)}
+branch_labels: Union[str, Sequence[str], None] = ${repr(branch_labels)}
+depends_on: Union[str, Sequence[str], None] = ${repr(depends_on)}
+
+
+def upgrade(engine_name: str) -> None:
+    globals()["upgrade_%s" % engine_name]()
+
+
+def downgrade(engine_name: str) -> None:
+    globals()["downgrade_%s" % engine_name]()
+
+<%
+    db_names = config.get_main_option("databases")
+%>
+
+## generate an "upgrade_<xyz>() / downgrade_<xyz>()" function
+## for each database name in the ini file.
+
+% for db_name in re.split(r',\s*', db_names):
+
+def upgrade_${db_name}() -> None:
+    ${context.get("%s_upgrades" % db_name, "pass")}
+
+
+def downgrade_${db_name}() -> None:
+    ${context.get("%s_downgrades" % db_name, "pass")}
+
+% endfor

.venv2/Lib/site-packages/alembic/testing/__init__.py

@@ -0,0 +1,29 @@
+from sqlalchemy.testing import config
+from sqlalchemy.testing import emits_warning
+from sqlalchemy.testing import engines
+from sqlalchemy.testing import exclusions
+from sqlalchemy.testing import mock
+from sqlalchemy.testing import provide_metadata
+from sqlalchemy.testing import skip_if
+from sqlalchemy.testing import uses_deprecated
+from sqlalchemy.testing.config import combinations
+from sqlalchemy.testing.config import fixture
+from sqlalchemy.testing.config import requirements as requires
+
+from .assertions import assert_raises
+from .assertions import assert_raises_message
+from .assertions import emits_python_deprecation_warning
+from .assertions import eq_
+from .assertions import eq_ignore_whitespace
+from .assertions import expect_raises
+from .assertions import expect_raises_message
+from .assertions import expect_sqlalchemy_deprecated
+from .assertions import expect_sqlalchemy_deprecated_20
+from .assertions import expect_warnings
+from .assertions import is_
+from .assertions import is_false
+from .assertions import is_not_
+from .assertions import is_true
+from .assertions import ne_
+from .fixtures import TestBase
+from .util import resolve_lambda

.venv2/Lib/site-packages/alembic/testing/assertions.py

@@ -0,0 +1,167 @@
+from __future__ import annotations
+
+import contextlib
+import re
+import sys
+from typing import Any
+from typing import Dict
+
+from sqlalchemy import exc as sa_exc
+from sqlalchemy.engine import default
+from sqlalchemy.testing.assertions import _expect_warnings
+from sqlalchemy.testing.assertions import eq_  # noqa
+from sqlalchemy.testing.assertions import is_  # noqa
+from sqlalchemy.testing.assertions import is_false  # noqa
+from sqlalchemy.testing.assertions import is_not_  # noqa
+from sqlalchemy.testing.assertions import is_true  # noqa
+from sqlalchemy.testing.assertions import ne_  # noqa
+from sqlalchemy.util import decorator
+
+from ..util import sqla_compat
+
+
+def _assert_proper_exception_context(exception):
+    """assert that any exception we're catching does not have a __context__
+    without a __cause__, and that __suppress_context__ is never set.
+
+    Python 3 will report nested as exceptions as "during the handling of
+    error X, error Y occurred". That's not what we want to do.  we want
+    these exceptions in a cause chain.
+
+    """
+
+    if (
+        exception.__context__ is not exception.__cause__
+        and not exception.__suppress_context__
+    ):
+        assert False, (
+            "Exception %r was correctly raised but did not set a cause, "
+            "within context %r as its cause."
+            % (exception, exception.__context__)
+        )
+
+
+def assert_raises(except_cls, callable_, *args, **kw):
+    return _assert_raises(except_cls, callable_, args, kw, check_context=True)
+
+
+def assert_raises_context_ok(except_cls, callable_, *args, **kw):
+    return _assert_raises(except_cls, callable_, args, kw)
+
+
+def assert_raises_message(except_cls, msg, callable_, *args, **kwargs):
+    return _assert_raises(
+        except_cls, callable_, args, kwargs, msg=msg, check_context=True
+    )
+
+
+def assert_raises_message_context_ok(
+    except_cls, msg, callable_, *args, **kwargs
+):
+    return _assert_raises(except_cls, callable_, args, kwargs, msg=msg)
+
+
+def _assert_raises(
+    except_cls, callable_, args, kwargs, msg=None, check_context=False
+):
+    with _expect_raises(except_cls, msg, check_context) as ec:
+        callable_(*args, **kwargs)
+    return ec.error
+
+
+class _ErrorContainer:
+    error: Any = None
+
+
+@contextlib.contextmanager
+def _expect_raises(except_cls, msg=None, check_context=False):
+    ec = _ErrorContainer()
+    if check_context:
+        are_we_already_in_a_traceback = sys.exc_info()[0]
+    try:
+        yield ec
+        success = False
+    except except_cls as err:
+        ec.error = err
+        success = True
+        if msg is not None:
+            assert re.search(msg, str(err), re.UNICODE), f"{msg} !~ {err}"
+        if check_context and not are_we_already_in_a_traceback:
+            _assert_proper_exception_context(err)
+        print(str(err).encode("utf-8"))
+
+    # assert outside the block so it works for AssertionError too !
+    assert success, "Callable did not raise an exception"
+
+
+def expect_raises(except_cls, check_context=True):
+    return _expect_raises(except_cls, check_context=check_context)
+
+
+def expect_raises_message(except_cls, msg, check_context=True):
+    return _expect_raises(except_cls, msg=msg, check_context=check_context)
+
+
+def eq_ignore_whitespace(a, b, msg=None):
+    a = re.sub(r"^\s+?|\n", "", a)
+    a = re.sub(r" {2,}", " ", a)
+    b = re.sub(r"^\s+?|\n", "", b)
+    b = re.sub(r" {2,}", " ", b)
+
+    assert a == b, msg or "%r != %r" % (a, b)
+
+
+_dialect_mods: Dict[Any, Any] = {}
+
+
+def _get_dialect(name):
+    if name is None or name == "default":
+        return default.DefaultDialect()
+    else:
+        d = sqla_compat._create_url(name).get_dialect()()
+
+        if name == "postgresql":
+            d.implicit_returning = True
+        elif name == "mssql":
+            d.legacy_schema_aliasing = False
+        return d
+
+
+def expect_warnings(*messages, **kw):
+    """Context manager which expects one or more warnings.
+
+    With no arguments, squelches all SAWarnings emitted via
+    sqlalchemy.util.warn and sqlalchemy.util.warn_limited.   Otherwise
+    pass string expressions that will match selected warnings via regex;
+    all non-matching warnings are sent through.
+
+    The expect version **asserts** that the warnings were in fact seen.
+
+    Note that the test suite sets SAWarning warnings to raise exceptions.
+
+    """
+    return _expect_warnings(Warning, messages, **kw)
+
+
+def emits_python_deprecation_warning(*messages):
+    """Decorator form of expect_warnings().
+
+    Note that emits_warning does **not** assert that the warnings
+    were in fact seen.
+
+    """
+
+    @decorator
+    def decorate(fn, *args, **kw):
+        with _expect_warnings(DeprecationWarning, assert_=False, *messages):
+            return fn(*args, **kw)
+
+    return decorate
+
+
+def expect_sqlalchemy_deprecated(*messages, **kw):
+    return _expect_warnings(sa_exc.SADeprecationWarning, messages, **kw)
+
+
+def expect_sqlalchemy_deprecated_20(*messages, **kw):
+    return _expect_warnings(sa_exc.RemovedIn20Warning, messages, **kw)

.venv2/Lib/site-packages/alembic/testing/env.py

@@ -0,0 +1,518 @@
+import importlib.machinery
+import os
+import shutil
+import textwrap
+
+from sqlalchemy.testing import config
+from sqlalchemy.testing import provision
+
+from . import util as testing_util
+from .. import command
+from .. import script
+from .. import util
+from ..script import Script
+from ..script import ScriptDirectory
+
+
+def _get_staging_directory():
+    if provision.FOLLOWER_IDENT:
+        return "scratch_%s" % provision.FOLLOWER_IDENT
+    else:
+        return "scratch"
+
+
+def staging_env(create=True, template="generic", sourceless=False):
+    cfg = _testing_config()
+    if create:
+        path = os.path.join(_get_staging_directory(), "scripts")
+        assert not os.path.exists(path), (
+            "staging directory %s already exists; poor cleanup?" % path
+        )
+
+        command.init(cfg, path, template=template)
+        if sourceless:
+            try:
+                # do an import so that a .pyc/.pyo is generated.
+                util.load_python_file(path, "env.py")
+            except AttributeError:
+                # we don't have the migration context set up yet
+                # so running the .env py throws this exception.
+                # theoretically we could be using py_compiler here to
+                # generate .pyc/.pyo without importing but not really
+                # worth it.
+                pass
+            assert sourceless in (
+                "pep3147_envonly",
+                "simple",
+                "pep3147_everything",
+            ), sourceless
+            make_sourceless(
+                os.path.join(path, "env.py"),
+                "pep3147" if "pep3147" in sourceless else "simple",
+            )
+
+    sc = script.ScriptDirectory.from_config(cfg)
+    return sc
+
+
+def clear_staging_env():
+    from sqlalchemy.testing import engines
+
+    engines.testing_reaper.close_all()
+    shutil.rmtree(_get_staging_directory(), True)
+
+
+def script_file_fixture(txt):
+    dir_ = os.path.join(_get_staging_directory(), "scripts")
+    path = os.path.join(dir_, "script.py.mako")
+    with open(path, "w") as f:
+        f.write(txt)
+
+
+def env_file_fixture(txt):
+    dir_ = os.path.join(_get_staging_directory(), "scripts")
+    txt = (
+        """
+from alembic import context
+
+config = context.config
+"""
+        + txt
+    )
+
+    path = os.path.join(dir_, "env.py")
+    pyc_path = util.pyc_file_from_path(path)
+    if pyc_path:
+        os.unlink(pyc_path)
+
+    with open(path, "w") as f:
+        f.write(txt)
+
+
+def _sqlite_file_db(tempname="foo.db", future=False, scope=None, **options):
+    dir_ = os.path.join(_get_staging_directory(), "scripts")
+    url = "sqlite:///%s/%s" % (dir_, tempname)
+    if scope and util.sqla_14:
+        options["scope"] = scope
+    return testing_util.testing_engine(url=url, future=future, options=options)
+
+
+def _sqlite_testing_config(sourceless=False, future=False):
+    dir_ = os.path.join(_get_staging_directory(), "scripts")
+    url = "sqlite:///%s/foo.db" % dir_
+
+    sqlalchemy_future = future or ("future" in config.db.__class__.__module__)
+
+    return _write_config_file(
+        """
+[alembic]
+script_location = %s
+sqlalchemy.url = %s
+sourceless = %s
+%s
+
+[loggers]
+keys = root,sqlalchemy
+
+[handlers]
+keys = console
+
+[logger_root]
+level = WARN
+handlers = console
+qualname =
+
+[logger_sqlalchemy]
+level = DEBUG
+handlers =
+qualname = sqlalchemy.engine
+
+[handler_console]
+class = StreamHandler
+args = (sys.stderr,)
+level = NOTSET
+formatter = generic
+
+[formatters]
+keys = generic
+
+[formatter_generic]
+format = %%(levelname)-5.5s [%%(name)s] %%(message)s
+datefmt = %%H:%%M:%%S
+    """
+        % (
+            dir_,
+            url,
+            "true" if sourceless else "false",
+            "sqlalchemy.future = true" if sqlalchemy_future else "",
+        )
+    )
+
+
+def _multi_dir_testing_config(sourceless=False, extra_version_location=""):
+    dir_ = os.path.join(_get_staging_directory(), "scripts")
+    sqlalchemy_future = "future" in config.db.__class__.__module__
+
+    url = "sqlite:///%s/foo.db" % dir_
+
+    return _write_config_file(
+        """
+[alembic]
+script_location = %s
+sqlalchemy.url = %s
+sqlalchemy.future = %s
+sourceless = %s
+version_locations = %%(here)s/model1/ %%(here)s/model2/ %%(here)s/model3/ %s
+
+[loggers]
+keys = root
+
+[handlers]
+keys = console
+
+[logger_root]
+level = WARN
+handlers = console
+qualname =
+
+[handler_console]
+class = StreamHandler
+args = (sys.stderr,)
+level = NOTSET
+formatter = generic
+
+[formatters]
+keys = generic
+
+[formatter_generic]
+format = %%(levelname)-5.5s [%%(name)s] %%(message)s
+datefmt = %%H:%%M:%%S
+    """
+        % (
+            dir_,
+            url,
+            "true" if sqlalchemy_future else "false",
+            "true" if sourceless else "false",
+            extra_version_location,
+        )
+    )
+
+
+def _no_sql_testing_config(dialect="postgresql", directives=""):
+    """use a postgresql url with no host so that
+    connections guaranteed to fail"""
+    dir_ = os.path.join(_get_staging_directory(), "scripts")
+    return _write_config_file(
+        """
+[alembic]
+script_location = %s
+sqlalchemy.url = %s://
+%s
+
+[loggers]
+keys = root
+
+[handlers]
+keys = console
+
+[logger_root]
+level = WARN
+handlers = console
+qualname =
+
+[handler_console]
+class = StreamHandler
+args = (sys.stderr,)
+level = NOTSET
+formatter = generic
+
+[formatters]
+keys = generic
+
+[formatter_generic]
+format = %%(levelname)-5.5s [%%(name)s] %%(message)s
+datefmt = %%H:%%M:%%S
+
+"""
+        % (dir_, dialect, directives)
+    )
+
+
+def _write_config_file(text):
+    cfg = _testing_config()
+    with open(cfg.config_file_name, "w") as f:
+        f.write(text)
+    return cfg
+
+
+def _testing_config():
+    from alembic.config import Config
+
+    if not os.access(_get_staging_directory(), os.F_OK):
+        os.mkdir(_get_staging_directory())
+    return Config(os.path.join(_get_staging_directory(), "test_alembic.ini"))
+
+
+def write_script(
+    scriptdir, rev_id, content, encoding="ascii", sourceless=False
+):
+    old = scriptdir.revision_map.get_revision(rev_id)
+    path = old.path
+
+    content = textwrap.dedent(content)
+    if encoding:
+        content = content.encode(encoding)
+    with open(path, "wb") as fp:
+        fp.write(content)
+    pyc_path = util.pyc_file_from_path(path)
+    if pyc_path:
+        os.unlink(pyc_path)
+    script = Script._from_path(scriptdir, path)
+    old = scriptdir.revision_map.get_revision(script.revision)
+    if old.down_revision != script.down_revision:
+        raise Exception(
+            "Can't change down_revision " "on a refresh operation."
+        )
+    scriptdir.revision_map.add_revision(script, _replace=True)
+
+    if sourceless:
+        make_sourceless(
+            path, "pep3147" if sourceless == "pep3147_everything" else "simple"
+        )
+
+
+def make_sourceless(path, style):
+    import py_compile
+
+    py_compile.compile(path)
+
+    if style == "simple":
+        pyc_path = util.pyc_file_from_path(path)
+        suffix = importlib.machinery.BYTECODE_SUFFIXES[0]
+        filepath, ext = os.path.splitext(path)
+        simple_pyc_path = filepath + suffix
+        shutil.move(pyc_path, simple_pyc_path)
+        pyc_path = simple_pyc_path
+    else:
+        assert style in ("pep3147", "simple")
+        pyc_path = util.pyc_file_from_path(path)
+
+    assert os.access(pyc_path, os.F_OK)
+
+    os.unlink(path)
+
+
+def three_rev_fixture(cfg):
+    a = util.rev_id()
+    b = util.rev_id()
+    c = util.rev_id()
+
+    script = ScriptDirectory.from_config(cfg)
+    script.generate_revision(a, "revision a", refresh=True, head="base")
+    write_script(
+        script,
+        a,
+        """\
+"Rev A"
+revision = '%s'
+down_revision = None
+
+from alembic import op
+
+
+def upgrade():
+    op.execute("CREATE STEP 1")
+
+
+def downgrade():
+    op.execute("DROP STEP 1")
+
+"""
+        % a,
+    )
+
+    script.generate_revision(b, "revision b", refresh=True, head=a)
+    write_script(
+        script,
+        b,
+        f"""# coding: utf-8
+"Rev B, méil, %3"
+revision = '{b}'
+down_revision = '{a}'
+
+from alembic import op
+
+
+def upgrade():
+    op.execute("CREATE STEP 2")
+
+
+def downgrade():
+    op.execute("DROP STEP 2")
+
+""",
+        encoding="utf-8",
+    )
+
+    script.generate_revision(c, "revision c", refresh=True, head=b)
+    write_script(
+        script,
+        c,
+        """\
+"Rev C"
+revision = '%s'
+down_revision = '%s'
+
+from alembic import op
+
+
+def upgrade():
+    op.execute("CREATE STEP 3")
+
+
+def downgrade():
+    op.execute("DROP STEP 3")
+
+"""
+        % (c, b),
+    )
+    return a, b, c
+
+
+def multi_heads_fixture(cfg, a, b, c):
+    """Create a multiple head fixture from the three-revs fixture"""
+
+    # a->b->c
+    #     -> d -> e
+    #     -> f
+    d = util.rev_id()
+    e = util.rev_id()
+    f = util.rev_id()
+
+    script = ScriptDirectory.from_config(cfg)
+    script.generate_revision(
+        d, "revision d from b", head=b, splice=True, refresh=True
+    )
+    write_script(
+        script,
+        d,
+        """\
+"Rev D"
+revision = '%s'
+down_revision = '%s'
+
+from alembic import op
+
+
+def upgrade():
+    op.execute("CREATE STEP 4")
+
+
+def downgrade():
+    op.execute("DROP STEP 4")
+
+"""
+        % (d, b),
+    )
+
+    script.generate_revision(
+        e, "revision e from d", head=d, splice=True, refresh=True
+    )
+    write_script(
+        script,
+        e,
+        """\
+"Rev E"
+revision = '%s'
+down_revision = '%s'
+
+from alembic import op
+
+
+def upgrade():
+    op.execute("CREATE STEP 5")
+
+
+def downgrade():
+    op.execute("DROP STEP 5")
+
+"""
+        % (e, d),
+    )
+
+    script.generate_revision(
+        f, "revision f from b", head=b, splice=True, refresh=True
+    )
+    write_script(
+        script,
+        f,
+        """\
+"Rev F"
+revision = '%s'
+down_revision = '%s'
+
+from alembic import op
+
+
+def upgrade():
+    op.execute("CREATE STEP 6")
+
+
+def downgrade():
+    op.execute("DROP STEP 6")
+
+"""
+        % (f, b),
+    )
+
+    return d, e, f
+
+
+def _multidb_testing_config(engines):
+    """alembic.ini fixture to work exactly with the 'multidb' template"""
+
+    dir_ = os.path.join(_get_staging_directory(), "scripts")
+
+    sqlalchemy_future = "future" in config.db.__class__.__module__
+
+    databases = ", ".join(engines.keys())
+    engines = "\n\n".join(
+        "[%s]\n" "sqlalchemy.url = %s" % (key, value.url)
+        for key, value in engines.items()
+    )
+
+    return _write_config_file(
+        """
+[alembic]
+script_location = %s
+sourceless = false
+sqlalchemy.future = %s
+databases = %s
+
+%s
+[loggers]
+keys = root
+
+[handlers]
+keys = console
+
+[logger_root]
+level = WARN
+handlers = console
+qualname =
+
+[handler_console]
+class = StreamHandler
+args = (sys.stderr,)
+level = NOTSET
+formatter = generic
+
+[formatters]
+keys = generic
+
+[formatter_generic]
+format = %%(levelname)-5.5s [%%(name)s] %%(message)s
+datefmt = %%H:%%M:%%S
+    """
+        % (dir_, "true" if sqlalchemy_future else "false", databases, engines)
+    )

.venv2/Lib/site-packages/alembic/testing/fixtures.py

@@ -0,0 +1,306 @@
+from __future__ import annotations
+
+import configparser
+from contextlib import contextmanager
+import io
+import re
+from typing import Any
+from typing import Dict
+
+from sqlalchemy import Column
+from sqlalchemy import inspect
+from sqlalchemy import MetaData
+from sqlalchemy import String
+from sqlalchemy import Table
+from sqlalchemy import testing
+from sqlalchemy import text
+from sqlalchemy.testing import config
+from sqlalchemy.testing import mock
+from sqlalchemy.testing.assertions import eq_
+from sqlalchemy.testing.fixtures import TablesTest as SQLAlchemyTablesTest
+from sqlalchemy.testing.fixtures import TestBase as SQLAlchemyTestBase
+
+import alembic
+from .assertions import _get_dialect
+from ..environment import EnvironmentContext
+from ..migration import MigrationContext
+from ..operations import Operations
+from ..util import sqla_compat
+from ..util.sqla_compat import create_mock_engine
+from ..util.sqla_compat import sqla_14
+from ..util.sqla_compat import sqla_2
+
+
+testing_config = configparser.ConfigParser()
+testing_config.read(["test.cfg"])
+
+
+class TestBase(SQLAlchemyTestBase):
+    is_sqlalchemy_future = sqla_2
+
+    @testing.fixture()
+    def ops_context(self, migration_context):
+        with migration_context.begin_transaction(_per_migration=True):
+            yield Operations(migration_context)
+
+    @testing.fixture
+    def migration_context(self, connection):
+        return MigrationContext.configure(
+            connection, opts=dict(transaction_per_migration=True)
+        )
+
+    @testing.fixture
+    def connection(self):
+        with config.db.connect() as conn:
+            yield conn
+
+
+class TablesTest(TestBase, SQLAlchemyTablesTest):
+    pass
+
+
+if sqla_14:
+    from sqlalchemy.testing.fixtures import FutureEngineMixin
+else:
+
+    class FutureEngineMixin:  # type:ignore[no-redef]
+        __requires__ = ("sqlalchemy_14",)
+
+
+FutureEngineMixin.is_sqlalchemy_future = True
+
+
+def capture_db(dialect="postgresql://"):
+    buf = []
+
+    def dump(sql, *multiparams, **params):
+        buf.append(str(sql.compile(dialect=engine.dialect)))
+
+    engine = create_mock_engine(dialect, dump)
+    return engine, buf
+
+
+_engs: Dict[Any, Any] = {}
+
+
+@contextmanager
+def capture_context_buffer(**kw):
+    if kw.pop("bytes_io", False):
+        buf = io.BytesIO()
+    else:
+        buf = io.StringIO()
+
+    kw.update({"dialect_name": "sqlite", "output_buffer": buf})
+    conf = EnvironmentContext.configure
+
+    def configure(*arg, **opt):
+        opt.update(**kw)
+        return conf(*arg, **opt)
+
+    with mock.patch.object(EnvironmentContext, "configure", configure):
+        yield buf
+
+
+@contextmanager
+def capture_engine_context_buffer(**kw):
+    from .env import _sqlite_file_db
+    from sqlalchemy import event
+
+    buf = io.StringIO()
+
+    eng = _sqlite_file_db()
+
+    conn = eng.connect()
+
+    @event.listens_for(conn, "before_cursor_execute")
+    def bce(conn, cursor, statement, parameters, context, executemany):
+        buf.write(statement + "\n")
+
+    kw.update({"connection": conn})
+    conf = EnvironmentContext.configure
+
+    def configure(*arg, **opt):
+        opt.update(**kw)
+        return conf(*arg, **opt)
+
+    with mock.patch.object(EnvironmentContext, "configure", configure):
+        yield buf
+
+
+def op_fixture(
+    dialect="default",
+    as_sql=False,
+    naming_convention=None,
+    literal_binds=False,
+    native_boolean=None,
+):
+    opts = {}
+    if naming_convention:
+        opts["target_metadata"] = MetaData(naming_convention=naming_convention)
+
+    class buffer_:
+        def __init__(self):
+            self.lines = []
+
+        def write(self, msg):
+            msg = msg.strip()
+            msg = re.sub(r"[\n\t]", "", msg)
+            if as_sql:
+                # the impl produces soft tabs,
+                # so search for blocks of 4 spaces
+                msg = re.sub(r"    ", "", msg)
+                msg = re.sub(r"\;\n*$", "", msg)
+
+            self.lines.append(msg)
+
+        def flush(self):
+            pass
+
+    buf = buffer_()
+
+    class ctx(MigrationContext):
+        def get_buf(self):
+            return buf
+
+        def clear_assertions(self):
+            buf.lines[:] = []
+
+        def assert_(self, *sql):
+            # TODO: make this more flexible about
+            # whitespace and such
+            eq_(buf.lines, [re.sub(r"[\n\t]", "", s) for s in sql])
+
+        def assert_contains(self, sql):
+            for stmt in buf.lines:
+                if re.sub(r"[\n\t]", "", sql) in stmt:
+                    return
+            else:
+                assert False, "Could not locate fragment %r in %r" % (
+                    sql,
+                    buf.lines,
+                )
+
+    if as_sql:
+        opts["as_sql"] = as_sql
+    if literal_binds:
+        opts["literal_binds"] = literal_binds
+    if not sqla_14 and dialect == "mariadb":
+        ctx_dialect = _get_dialect("mysql")
+        ctx_dialect.server_version_info = (10, 4, 0, "MariaDB")
+
+    else:
+        ctx_dialect = _get_dialect(dialect)
+    if native_boolean is not None:
+        ctx_dialect.supports_native_boolean = native_boolean
+        # this is new as of SQLAlchemy 1.2.7 and is used by SQL Server,
+        # which breaks assumptions in the alembic test suite
+        ctx_dialect.non_native_boolean_check_constraint = True
+    if not as_sql:
+
+        def execute(stmt, *multiparam, **param):
+            if isinstance(stmt, str):
+                stmt = text(stmt)
+            assert stmt.supports_execution
+            sql = str(stmt.compile(dialect=ctx_dialect))
+
+            buf.write(sql)
+
+        connection = mock.Mock(dialect=ctx_dialect, execute=execute)
+    else:
+        opts["output_buffer"] = buf
+        connection = None
+    context = ctx(ctx_dialect, connection, opts)
+
+    alembic.op._proxy = Operations(context)
+    return context
+
+
+class AlterColRoundTripFixture:
+    # since these tests are about syntax, use more recent SQLAlchemy as some of
+    # the type / server default compare logic might not work on older
+    # SQLAlchemy versions as seems to be the case for SQLAlchemy 1.1 on Oracle
+
+    __requires__ = ("alter_column",)
+
+    def setUp(self):
+        self.conn = config.db.connect()
+        self.ctx = MigrationContext.configure(self.conn)
+        self.op = Operations(self.ctx)
+        self.metadata = MetaData()
+
+    def _compare_type(self, t1, t2):
+        c1 = Column("q", t1)
+        c2 = Column("q", t2)
+        assert not self.ctx.impl.compare_type(
+            c1, c2
+        ), "Type objects %r and %r didn't compare as equivalent" % (t1, t2)
+
+    def _compare_server_default(self, t1, s1, t2, s2):
+        c1 = Column("q", t1, server_default=s1)
+        c2 = Column("q", t2, server_default=s2)
+        assert not self.ctx.impl.compare_server_default(
+            c1, c2, s2, s1
+        ), "server defaults %r and %r didn't compare as equivalent" % (s1, s2)
+
+    def tearDown(self):
+        sqla_compat._safe_rollback_connection_transaction(self.conn)
+        with self.conn.begin():
+            self.metadata.drop_all(self.conn)
+        self.conn.close()
+
+    def _run_alter_col(self, from_, to_, compare=None):
+        column = Column(
+            from_.get("name", "colname"),
+            from_.get("type", String(10)),
+            nullable=from_.get("nullable", True),
+            server_default=from_.get("server_default", None),
+            # comment=from_.get("comment", None)
+        )
+        t = Table("x", self.metadata, column)
+
+        with sqla_compat._ensure_scope_for_ddl(self.conn):
+            t.create(self.conn)
+            insp = inspect(self.conn)
+            old_col = insp.get_columns("x")[0]
+
+            # TODO: conditional comment support
+            self.op.alter_column(
+                "x",
+                column.name,
+                existing_type=column.type,
+                existing_server_default=column.server_default
+                if column.server_default is not None
+                else False,
+                existing_nullable=True if column.nullable else False,
+                # existing_comment=column.comment,
+                nullable=to_.get("nullable", None),
+                # modify_comment=False,
+                server_default=to_.get("server_default", False),
+                new_column_name=to_.get("name", None),
+                type_=to_.get("type", None),
+            )
+
+        insp = inspect(self.conn)
+        new_col = insp.get_columns("x")[0]
+
+        if compare is None:
+            compare = to_
+
+        eq_(
+            new_col["name"],
+            compare["name"] if "name" in compare else column.name,
+        )
+        self._compare_type(
+            new_col["type"], compare.get("type", old_col["type"])
+        )
+        eq_(new_col["nullable"], compare.get("nullable", column.nullable))
+        self._compare_server_default(
+            new_col["type"],
+            new_col.get("default", None),
+            compare.get("type", old_col["type"]),
+            compare["server_default"].text
+            if "server_default" in compare
+            else column.server_default.arg.text
+            if column.server_default is not None
+            else None,
+        )

.venv2/Lib/site-packages/alembic/testing/plugin/bootstrap.py

@@ -0,0 +1,4 @@
+"""
+Bootstrapper for test framework plugins.
+
+"""

.venv2/Lib/site-packages/alembic/testing/requirements.py

@@ -0,0 +1,210 @@
+from sqlalchemy.testing.requirements import Requirements
+
+from alembic import util
+from alembic.util import sqla_compat
+from ..testing import exclusions
+
+
+class SuiteRequirements(Requirements):
+    @property
+    def schemas(self):
+        """Target database must support external schemas, and have one
+        named 'test_schema'."""
+
+        return exclusions.open()
+
+    @property
+    def autocommit_isolation(self):
+        """target database should support 'AUTOCOMMIT' isolation level"""
+
+        return exclusions.closed()
+
+    @property
+    def materialized_views(self):
+        """needed for sqlalchemy compat"""
+        return exclusions.closed()
+
+    @property
+    def unique_constraint_reflection(self):
+        def doesnt_have_check_uq_constraints(config):
+            from sqlalchemy import inspect
+
+            insp = inspect(config.db)
+            try:
+                insp.get_unique_constraints("x")
+            except NotImplementedError:
+                return True
+            except TypeError:
+                return True
+            except Exception:
+                pass
+            return False
+
+        return exclusions.skip_if(doesnt_have_check_uq_constraints)
+
+    @property
+    def sequences(self):
+        """Target database must support SEQUENCEs."""
+
+        return exclusions.only_if(
+            [lambda config: config.db.dialect.supports_sequences],
+            "no sequence support",
+        )
+
+    @property
+    def foreign_key_match(self):
+        return exclusions.open()
+
+    @property
+    def foreign_key_constraint_reflection(self):
+        return exclusions.open()
+
+    @property
+    def check_constraints_w_enforcement(self):
+        """Target database must support check constraints
+        and also enforce them."""
+
+        return exclusions.open()
+
+    @property
+    def reflects_pk_names(self):
+        return exclusions.closed()
+
+    @property
+    def reflects_fk_options(self):
+        return exclusions.closed()
+
+    @property
+    def sqlalchemy_14(self):
+        return exclusions.skip_if(
+            lambda config: not util.sqla_14,
+            "SQLAlchemy 1.4 or greater required",
+        )
+
+    @property
+    def sqlalchemy_1x(self):
+        return exclusions.skip_if(
+            lambda config: util.sqla_2,
+            "SQLAlchemy 1.x test",
+        )
+
+    @property
+    def sqlalchemy_2(self):
+        return exclusions.skip_if(
+            lambda config: not util.sqla_2,
+            "SQLAlchemy 2.x test",
+        )
+
+    @property
+    def asyncio(self):
+        def go(config):
+            try:
+                import greenlet  # noqa: F401
+            except ImportError:
+                return False
+            else:
+                return True
+
+        return self.sqlalchemy_14 + exclusions.only_if(go)
+
+    @property
+    def comments(self):
+        return exclusions.only_if(
+            lambda config: config.db.dialect.supports_comments
+        )
+
+    @property
+    def alter_column(self):
+        return exclusions.open()
+
+    @property
+    def computed_columns(self):
+        return exclusions.closed()
+
+    @property
+    def computed_columns_api(self):
+        return exclusions.only_if(
+            exclusions.BooleanPredicate(sqla_compat.has_computed)
+        )
+
+    @property
+    def computed_reflects_normally(self):
+        return exclusions.only_if(
+            exclusions.BooleanPredicate(sqla_compat.has_computed_reflection)
+        )
+
+    @property
+    def computed_reflects_as_server_default(self):
+        return exclusions.closed()
+
+    @property
+    def computed_doesnt_reflect_as_server_default(self):
+        return exclusions.closed()
+
+    @property
+    def autoincrement_on_composite_pk(self):
+        return exclusions.closed()
+
+    @property
+    def fk_ondelete_is_reflected(self):
+        return exclusions.closed()
+
+    @property
+    def fk_onupdate_is_reflected(self):
+        return exclusions.closed()
+
+    @property
+    def fk_onupdate(self):
+        return exclusions.open()
+
+    @property
+    def fk_ondelete_restrict(self):
+        return exclusions.open()
+
+    @property
+    def fk_onupdate_restrict(self):
+        return exclusions.open()
+
+    @property
+    def fk_ondelete_noaction(self):
+        return exclusions.open()
+
+    @property
+    def fk_initially(self):
+        return exclusions.closed()
+
+    @property
+    def fk_deferrable(self):
+        return exclusions.closed()
+
+    @property
+    def fk_deferrable_is_reflected(self):
+        return exclusions.closed()
+
+    @property
+    def fk_names(self):
+        return exclusions.open()
+
+    @property
+    def integer_subtype_comparisons(self):
+        return exclusions.open()
+
+    @property
+    def no_name_normalize(self):
+        return exclusions.skip_if(
+            lambda config: config.db.dialect.requires_name_normalize
+        )
+
+    @property
+    def identity_columns(self):
+        return exclusions.closed()
+
+    @property
+    def identity_columns_alter(self):
+        return exclusions.closed()
+
+    @property
+    def identity_columns_api(self):
+        return exclusions.only_if(
+            exclusions.BooleanPredicate(sqla_compat.has_identity)
+        )

.venv2/Lib/site-packages/alembic/testing/schemacompare.py

@@ -0,0 +1,169 @@
+from itertools import zip_longest
+
+from sqlalchemy import schema
+from sqlalchemy.sql.elements import ClauseList
+
+
+class CompareTable:
+    def __init__(self, table):
+        self.table = table
+
+    def __eq__(self, other):
+        if self.table.name != other.name or self.table.schema != other.schema:
+            return False
+
+        for c1, c2 in zip_longest(self.table.c, other.c):
+            if (c1 is None and c2 is not None) or (
+                c2 is None and c1 is not None
+            ):
+                return False
+            if CompareColumn(c1) != c2:
+                return False
+
+        return True
+
+        # TODO: compare constraints, indexes
+
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
+
+class CompareColumn:
+    def __init__(self, column):
+        self.column = column
+
+    def __eq__(self, other):
+        return (
+            self.column.name == other.name
+            and self.column.nullable == other.nullable
+        )
+        # TODO: datatypes etc
+
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
+
+class CompareIndex:
+    def __init__(self, index, name_only=False):
+        self.index = index
+        self.name_only = name_only
+
+    def __eq__(self, other):
+        if self.name_only:
+            return self.index.name == other.name
+        else:
+            return (
+                str(schema.CreateIndex(self.index))
+                == str(schema.CreateIndex(other))
+                and self.index.dialect_kwargs == other.dialect_kwargs
+            )
+
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
+    def __repr__(self):
+        expr = ClauseList(*self.index.expressions)
+        try:
+            expr_str = expr.compile().string
+        except Exception:
+            expr_str = str(expr)
+        return f"<CompareIndex {self.index.name}({expr_str})>"
+
+
+class CompareCheckConstraint:
+    def __init__(self, constraint):
+        self.constraint = constraint
+
+    def __eq__(self, other):
+        return (
+            isinstance(other, schema.CheckConstraint)
+            and self.constraint.name == other.name
+            and (str(self.constraint.sqltext) == str(other.sqltext))
+            and (other.table.name == self.constraint.table.name)
+            and other.table.schema == self.constraint.table.schema
+        )
+
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
+
+class CompareForeignKey:
+    def __init__(self, constraint):
+        self.constraint = constraint
+
+    def __eq__(self, other):
+        r1 = (
+            isinstance(other, schema.ForeignKeyConstraint)
+            and self.constraint.name == other.name
+            and (other.table.name == self.constraint.table.name)
+            and other.table.schema == self.constraint.table.schema
+        )
+        if not r1:
+            return False
+        for c1, c2 in zip_longest(self.constraint.columns, other.columns):
+            if (c1 is None and c2 is not None) or (
+                c2 is None and c1 is not None
+            ):
+                return False
+            if CompareColumn(c1) != c2:
+                return False
+        return True
+
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
+
+class ComparePrimaryKey:
+    def __init__(self, constraint):
+        self.constraint = constraint
+
+    def __eq__(self, other):
+        r1 = (
+            isinstance(other, schema.PrimaryKeyConstraint)
+            and self.constraint.name == other.name
+            and (other.table.name == self.constraint.table.name)
+            and other.table.schema == self.constraint.table.schema
+        )
+        if not r1:
+            return False
+
+        for c1, c2 in zip_longest(self.constraint.columns, other.columns):
+            if (c1 is None and c2 is not None) or (
+                c2 is None and c1 is not None
+            ):
+                return False
+            if CompareColumn(c1) != c2:
+                return False
+
+        return True
+
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
+
+class CompareUniqueConstraint:
+    def __init__(self, constraint):
+        self.constraint = constraint
+
+    def __eq__(self, other):
+        r1 = (
+            isinstance(other, schema.UniqueConstraint)
+            and self.constraint.name == other.name
+            and (other.table.name == self.constraint.table.name)
+            and other.table.schema == self.constraint.table.schema
+        )
+        if not r1:
+            return False
+
+        for c1, c2 in zip_longest(self.constraint.columns, other.columns):
+            if (c1 is None and c2 is not None) or (
+                c2 is None and c1 is not None
+            ):
+                return False
+            if CompareColumn(c1) != c2:
+                return False
+
+        return True
+
+    def __ne__(self, other):
+        return not self.__eq__(other)

.venv2/Lib/site-packages/alembic/testing/suite/__init__.py

@@ -0,0 +1,7 @@
+from .test_autogen_comments import *  # noqa
+from .test_autogen_computed import *  # noqa
+from .test_autogen_diffs import *  # noqa
+from .test_autogen_fks import *  # noqa
+from .test_autogen_identity import *  # noqa
+from .test_environment import *  # noqa
+from .test_op import *  # noqa

.venv2/Lib/site-packages/alembic/testing/suite/_autogen_fixtures.py

@@ -0,0 +1,335 @@
+from __future__ import annotations
+
+from typing import Any
+from typing import Dict
+from typing import Set
+
+from sqlalchemy import CHAR
+from sqlalchemy import CheckConstraint
+from sqlalchemy import Column
+from sqlalchemy import event
+from sqlalchemy import ForeignKey
+from sqlalchemy import Index
+from sqlalchemy import inspect
+from sqlalchemy import Integer
+from sqlalchemy import MetaData
+from sqlalchemy import Numeric
+from sqlalchemy import String
+from sqlalchemy import Table
+from sqlalchemy import Text
+from sqlalchemy import text
+from sqlalchemy import UniqueConstraint
+
+from ... import autogenerate
+from ... import util
+from ...autogenerate import api
+from ...ddl.base import _fk_spec
+from ...migration import MigrationContext
+from ...operations import ops
+from ...testing import config
+from ...testing import eq_
+from ...testing.env import clear_staging_env
+from ...testing.env import staging_env
+
+names_in_this_test: Set[Any] = set()
+
+
+@event.listens_for(Table, "after_parent_attach")
+def new_table(table, parent):
+    names_in_this_test.add(table.name)
+
+
+def _default_include_object(obj, name, type_, reflected, compare_to):
+    if type_ == "table":
+        return name in names_in_this_test
+    else:
+        return True
+
+
+_default_object_filters: Any = _default_include_object
+
+_default_name_filters: Any = None
+
+
+class ModelOne:
+    __requires__ = ("unique_constraint_reflection",)
+
+    schema: Any = None
+
+    @classmethod
+    def _get_db_schema(cls):
+        schema = cls.schema
+
+        m = MetaData(schema=schema)
+
+        Table(
+            "user",
+            m,
+            Column("id", Integer, primary_key=True),
+            Column("name", String(50)),
+            Column("a1", Text),
+            Column("pw", String(50)),
+            Index("pw_idx", "pw"),
+        )
+
+        Table(
+            "address",
+            m,
+            Column("id", Integer, primary_key=True),
+            Column("email_address", String(100), nullable=False),
+        )
+
+        Table(
+            "order",
+            m,
+            Column("order_id", Integer, primary_key=True),
+            Column(
+                "amount",
+                Numeric(8, 2),
+                nullable=False,
+                server_default=text("0"),
+            ),
+            CheckConstraint("amount >= 0", name="ck_order_amount"),
+        )
+
+        Table(
+            "extra",
+            m,
+            Column("x", CHAR),
+            Column("uid", Integer, ForeignKey("user.id")),
+        )
+
+        return m
+
+    @classmethod
+    def _get_model_schema(cls):
+        schema = cls.schema
+
+        m = MetaData(schema=schema)
+
+        Table(
+            "user",
+            m,
+            Column("id", Integer, primary_key=True),
+            Column("name", String(50), nullable=False),
+            Column("a1", Text, server_default="x"),
+        )
+
+        Table(
+            "address",
+            m,
+            Column("id", Integer, primary_key=True),
+            Column("email_address", String(100), nullable=False),
+            Column("street", String(50)),
+            UniqueConstraint("email_address", name="uq_email"),
+        )
+
+        Table(
+            "order",
+            m,
+            Column("order_id", Integer, primary_key=True),
+            Column(
+                "amount",
+                Numeric(10, 2),
+                nullable=True,
+                server_default=text("0"),
+            ),
+            Column("user_id", Integer, ForeignKey("user.id")),
+            CheckConstraint("amount > -1", name="ck_order_amount"),
+        )
+
+        Table(
+            "item",
+            m,
+            Column("id", Integer, primary_key=True),
+            Column("description", String(100)),
+            Column("order_id", Integer, ForeignKey("order.order_id")),
+            CheckConstraint("len(description) > 5"),
+        )
+        return m
+
+
+class _ComparesFKs:
+    def _assert_fk_diff(
+        self,
+        diff,
+        type_,
+        source_table,
+        source_columns,
+        target_table,
+        target_columns,
+        name=None,
+        conditional_name=None,
+        source_schema=None,
+        onupdate=None,
+        ondelete=None,
+        initially=None,
+        deferrable=None,
+    ):
+        # the public API for ForeignKeyConstraint was not very rich
+        # in 0.7, 0.8, so here we use the well-known but slightly
+        # private API to get at its elements
+        (
+            fk_source_schema,
+            fk_source_table,
+            fk_source_columns,
+            fk_target_schema,
+            fk_target_table,
+            fk_target_columns,
+            fk_onupdate,
+            fk_ondelete,
+            fk_deferrable,
+            fk_initially,
+        ) = _fk_spec(diff[1])
+
+        eq_(diff[0], type_)
+        eq_(fk_source_table, source_table)
+        eq_(fk_source_columns, source_columns)
+        eq_(fk_target_table, target_table)
+        eq_(fk_source_schema, source_schema)
+        eq_(fk_onupdate, onupdate)
+        eq_(fk_ondelete, ondelete)
+        eq_(fk_initially, initially)
+        eq_(fk_deferrable, deferrable)
+
+        eq_([elem.column.name for elem in diff[1].elements], target_columns)
+        if conditional_name is not None:
+            if conditional_name == "servergenerated":
+                fks = inspect(self.bind).get_foreign_keys(source_table)
+                server_fk_name = fks[0]["name"]
+                eq_(diff[1].name, server_fk_name)
+            else:
+                eq_(diff[1].name, conditional_name)
+        else:
+            eq_(diff[1].name, name)
+
+
+class AutogenTest(_ComparesFKs):
+    def _flatten_diffs(self, diffs):
+        for d in diffs:
+            if isinstance(d, list):
+                yield from self._flatten_diffs(d)
+            else:
+                yield d
+
+    @classmethod
+    def _get_bind(cls):
+        return config.db
+
+    configure_opts: Dict[Any, Any] = {}
+
+    @classmethod
+    def setup_class(cls):
+        staging_env()
+        cls.bind = cls._get_bind()
+        cls.m1 = cls._get_db_schema()
+        cls.m1.create_all(cls.bind)
+        cls.m2 = cls._get_model_schema()
+
+    @classmethod
+    def teardown_class(cls):
+        cls.m1.drop_all(cls.bind)
+        clear_staging_env()
+
+    def setUp(self):
+        self.conn = conn = self.bind.connect()
+        ctx_opts = {
+            "compare_type": True,
+            "compare_server_default": True,
+            "target_metadata": self.m2,
+            "upgrade_token": "upgrades",
+            "downgrade_token": "downgrades",
+            "alembic_module_prefix": "op.",
+            "sqlalchemy_module_prefix": "sa.",
+            "include_object": _default_object_filters,
+            "include_name": _default_name_filters,
+        }
+        if self.configure_opts:
+            ctx_opts.update(self.configure_opts)
+        self.context = context = MigrationContext.configure(
+            connection=conn, opts=ctx_opts
+        )
+
+        self.autogen_context = api.AutogenContext(context, self.m2)
+
+    def tearDown(self):
+        self.conn.close()
+
+    def _update_context(
+        self, object_filters=None, name_filters=None, include_schemas=None
+    ):
+        if include_schemas is not None:
+            self.autogen_context.opts["include_schemas"] = include_schemas
+        if object_filters is not None:
+            self.autogen_context._object_filters = [object_filters]
+        if name_filters is not None:
+            self.autogen_context._name_filters = [name_filters]
+        return self.autogen_context
+
+
+class AutogenFixtureTest(_ComparesFKs):
+    def _fixture(
+        self,
+        m1,
+        m2,
+        include_schemas=False,
+        opts=None,
+        object_filters=_default_object_filters,
+        name_filters=_default_name_filters,
+        return_ops=False,
+        max_identifier_length=None,
+    ):
+        if max_identifier_length:
+            dialect = self.bind.dialect
+            existing_length = dialect.max_identifier_length
+            dialect.max_identifier_length = (
+                dialect._user_defined_max_identifier_length
+            ) = max_identifier_length
+        try:
+            self._alembic_metadata, model_metadata = m1, m2
+            for m in util.to_list(self._alembic_metadata):
+                m.create_all(self.bind)
+
+            with self.bind.connect() as conn:
+                ctx_opts = {
+                    "compare_type": True,
+                    "compare_server_default": True,
+                    "target_metadata": model_metadata,
+                    "upgrade_token": "upgrades",
+                    "downgrade_token": "downgrades",
+                    "alembic_module_prefix": "op.",
+                    "sqlalchemy_module_prefix": "sa.",
+                    "include_object": object_filters,
+                    "include_name": name_filters,
+                    "include_schemas": include_schemas,
+                }
+                if opts:
+                    ctx_opts.update(opts)
+                self.context = context = MigrationContext.configure(
+                    connection=conn, opts=ctx_opts
+                )
+
+                autogen_context = api.AutogenContext(context, model_metadata)
+                uo = ops.UpgradeOps(ops=[])
+                autogenerate._produce_net_changes(autogen_context, uo)
+
+                if return_ops:
+                    return uo
+                else:
+                    return uo.as_diffs()
+        finally:
+            if max_identifier_length:
+                dialect = self.bind.dialect
+                dialect.max_identifier_length = (
+                    dialect._user_defined_max_identifier_length
+                ) = existing_length
+
+    def setUp(self):
+        staging_env()
+        self.bind = config.db
+
+    def tearDown(self):
+        if hasattr(self, "_alembic_metadata"):
+            for m in util.to_list(self._alembic_metadata):
+                m.drop_all(self.bind)
+        clear_staging_env()

.venv2/Lib/site-packages/alembic/testing/suite/test_autogen_comments.py

@@ -0,0 +1,242 @@
+from sqlalchemy import Column
+from sqlalchemy import Float
+from sqlalchemy import MetaData
+from sqlalchemy import String
+from sqlalchemy import Table
+
+from ._autogen_fixtures import AutogenFixtureTest
+from ...testing import eq_
+from ...testing import mock
+from ...testing import TestBase
+
+
+class AutogenerateCommentsTest(AutogenFixtureTest, TestBase):
+    __backend__ = True
+
+    __requires__ = ("comments",)
+
+    def test_existing_table_comment_no_change(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "some_table",
+            m1,
+            Column("test", String(10), primary_key=True),
+            comment="this is some table",
+        )
+
+        Table(
+            "some_table",
+            m2,
+            Column("test", String(10), primary_key=True),
+            comment="this is some table",
+        )
+
+        diffs = self._fixture(m1, m2)
+
+        eq_(diffs, [])
+
+    def test_add_table_comment(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table("some_table", m1, Column("test", String(10), primary_key=True))
+
+        Table(
+            "some_table",
+            m2,
+            Column("test", String(10), primary_key=True),
+            comment="this is some table",
+        )
+
+        diffs = self._fixture(m1, m2)
+
+        eq_(diffs[0][0], "add_table_comment")
+        eq_(diffs[0][1].comment, "this is some table")
+        eq_(diffs[0][2], None)
+
+    def test_remove_table_comment(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "some_table",
+            m1,
+            Column("test", String(10), primary_key=True),
+            comment="this is some table",
+        )
+
+        Table("some_table", m2, Column("test", String(10), primary_key=True))
+
+        diffs = self._fixture(m1, m2)
+
+        eq_(diffs[0][0], "remove_table_comment")
+        eq_(diffs[0][1].comment, None)
+
+    def test_alter_table_comment(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "some_table",
+            m1,
+            Column("test", String(10), primary_key=True),
+            comment="this is some table",
+        )
+
+        Table(
+            "some_table",
+            m2,
+            Column("test", String(10), primary_key=True),
+            comment="this is also some table",
+        )
+
+        diffs = self._fixture(m1, m2)
+
+        eq_(diffs[0][0], "add_table_comment")
+        eq_(diffs[0][1].comment, "this is also some table")
+        eq_(diffs[0][2], "this is some table")
+
+    def test_existing_column_comment_no_change(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "some_table",
+            m1,
+            Column("test", String(10), primary_key=True),
+            Column("amount", Float, comment="the amount"),
+        )
+
+        Table(
+            "some_table",
+            m2,
+            Column("test", String(10), primary_key=True),
+            Column("amount", Float, comment="the amount"),
+        )
+
+        diffs = self._fixture(m1, m2)
+
+        eq_(diffs, [])
+
+    def test_add_column_comment(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "some_table",
+            m1,
+            Column("test", String(10), primary_key=True),
+            Column("amount", Float),
+        )
+
+        Table(
+            "some_table",
+            m2,
+            Column("test", String(10), primary_key=True),
+            Column("amount", Float, comment="the amount"),
+        )
+
+        diffs = self._fixture(m1, m2)
+        eq_(
+            diffs,
+            [
+                [
+                    (
+                        "modify_comment",
+                        None,
+                        "some_table",
+                        "amount",
+                        {
+                            "existing_nullable": True,
+                            "existing_type": mock.ANY,
+                            "existing_server_default": False,
+                        },
+                        None,
+                        "the amount",
+                    )
+                ]
+            ],
+        )
+
+    def test_remove_column_comment(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "some_table",
+            m1,
+            Column("test", String(10), primary_key=True),
+            Column("amount", Float, comment="the amount"),
+        )
+
+        Table(
+            "some_table",
+            m2,
+            Column("test", String(10), primary_key=True),
+            Column("amount", Float),
+        )
+
+        diffs = self._fixture(m1, m2)
+        eq_(
+            diffs,
+            [
+                [
+                    (
+                        "modify_comment",
+                        None,
+                        "some_table",
+                        "amount",
+                        {
+                            "existing_nullable": True,
+                            "existing_type": mock.ANY,
+                            "existing_server_default": False,
+                        },
+                        "the amount",
+                        None,
+                    )
+                ]
+            ],
+        )
+
+    def test_alter_column_comment(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "some_table",
+            m1,
+            Column("test", String(10), primary_key=True),
+            Column("amount", Float, comment="the amount"),
+        )
+
+        Table(
+            "some_table",
+            m2,
+            Column("test", String(10), primary_key=True),
+            Column("amount", Float, comment="the adjusted amount"),
+        )
+
+        diffs = self._fixture(m1, m2)
+
+        eq_(
+            diffs,
+            [
+                [
+                    (
+                        "modify_comment",
+                        None,
+                        "some_table",
+                        "amount",
+                        {
+                            "existing_nullable": True,
+                            "existing_type": mock.ANY,
+                            "existing_server_default": False,
+                        },
+                        "the amount",
+                        "the adjusted amount",
+                    )
+                ]
+            ],
+        )

.venv2/Lib/site-packages/alembic/testing/suite/test_autogen_computed.py

@@ -0,0 +1,203 @@
+import sqlalchemy as sa
+from sqlalchemy import Column
+from sqlalchemy import Integer
+from sqlalchemy import MetaData
+from sqlalchemy import Table
+
+from ._autogen_fixtures import AutogenFixtureTest
+from ... import testing
+from ...testing import config
+from ...testing import eq_
+from ...testing import exclusions
+from ...testing import is_
+from ...testing import is_true
+from ...testing import mock
+from ...testing import TestBase
+
+
+class AutogenerateComputedTest(AutogenFixtureTest, TestBase):
+    __requires__ = ("computed_columns",)
+    __backend__ = True
+
+    def test_add_computed_column(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table("user", m1, Column("id", Integer, primary_key=True))
+
+        Table(
+            "user",
+            m2,
+            Column("id", Integer, primary_key=True),
+            Column("foo", Integer, sa.Computed("5")),
+        )
+
+        diffs = self._fixture(m1, m2)
+
+        eq_(diffs[0][0], "add_column")
+        eq_(diffs[0][2], "user")
+        eq_(diffs[0][3].name, "foo")
+        c = diffs[0][3].computed
+
+        is_true(isinstance(c, sa.Computed))
+        is_(c.persisted, None)
+        eq_(str(c.sqltext), "5")
+
+    def test_remove_computed_column(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "user",
+            m1,
+            Column("id", Integer, primary_key=True),
+            Column("foo", Integer, sa.Computed("5")),
+        )
+
+        Table("user", m2, Column("id", Integer, primary_key=True))
+
+        diffs = self._fixture(m1, m2)
+
+        eq_(diffs[0][0], "remove_column")
+        eq_(diffs[0][2], "user")
+        c = diffs[0][3]
+        eq_(c.name, "foo")
+
+        if config.requirements.computed_reflects_normally.enabled:
+            is_true(isinstance(c.computed, sa.Computed))
+        else:
+            is_(c.computed, None)
+
+        if config.requirements.computed_reflects_as_server_default.enabled:
+            is_true(isinstance(c.server_default, sa.DefaultClause))
+            eq_(str(c.server_default.arg.text), "5")
+        elif config.requirements.computed_reflects_normally.enabled:
+            is_true(isinstance(c.computed, sa.Computed))
+        else:
+            is_(c.computed, None)
+
+    @testing.combinations(
+        lambda: (None, sa.Computed("bar*5")),
+        (lambda: (sa.Computed("bar*5"), None)),
+        lambda: (
+            sa.Computed("bar*5"),
+            sa.Computed("bar * 42", persisted=True),
+        ),
+        lambda: (sa.Computed("bar*5"), sa.Computed("bar * 42")),
+    )
+    @config.requirements.computed_reflects_normally
+    def test_cant_change_computed_warning(self, test_case):
+        arg_before, arg_after = testing.resolve_lambda(test_case, **locals())
+        m1 = MetaData()
+        m2 = MetaData()
+
+        arg_before = [] if arg_before is None else [arg_before]
+        arg_after = [] if arg_after is None else [arg_after]
+
+        Table(
+            "user",
+            m1,
+            Column("id", Integer, primary_key=True),
+            Column("bar", Integer),
+            Column("foo", Integer, *arg_before),
+        )
+
+        Table(
+            "user",
+            m2,
+            Column("id", Integer, primary_key=True),
+            Column("bar", Integer),
+            Column("foo", Integer, *arg_after),
+        )
+
+        with mock.patch("alembic.util.warn") as mock_warn:
+            diffs = self._fixture(m1, m2)
+
+        eq_(
+            mock_warn.mock_calls,
+            [mock.call("Computed default on user.foo cannot be modified")],
+        )
+
+        eq_(list(diffs), [])
+
+    @testing.combinations(
+        lambda: (None, None),
+        lambda: (sa.Computed("5"), sa.Computed("5")),
+        lambda: (sa.Computed("bar*5"), sa.Computed("bar*5")),
+        (
+            lambda: (sa.Computed("bar*5"), None),
+            config.requirements.computed_doesnt_reflect_as_server_default,
+        ),
+    )
+    def test_computed_unchanged(self, test_case):
+        arg_before, arg_after = testing.resolve_lambda(test_case, **locals())
+        m1 = MetaData()
+        m2 = MetaData()
+
+        arg_before = [] if arg_before is None else [arg_before]
+        arg_after = [] if arg_after is None else [arg_after]
+
+        Table(
+            "user",
+            m1,
+            Column("id", Integer, primary_key=True),
+            Column("bar", Integer),
+            Column("foo", Integer, *arg_before),
+        )
+
+        Table(
+            "user",
+            m2,
+            Column("id", Integer, primary_key=True),
+            Column("bar", Integer),
+            Column("foo", Integer, *arg_after),
+        )
+
+        with mock.patch("alembic.util.warn") as mock_warn:
+            diffs = self._fixture(m1, m2)
+        eq_(mock_warn.mock_calls, [])
+
+        eq_(list(diffs), [])
+
+    @config.requirements.computed_reflects_as_server_default
+    def test_remove_computed_default_on_computed(self):
+        """Asserts the current behavior which is that on PG and Oracle,
+        the GENERATED ALWAYS AS is reflected as a server default which we can't
+        tell is actually "computed", so these come out as a modification to
+        the server default.
+
+        """
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "user",
+            m1,
+            Column("id", Integer, primary_key=True),
+            Column("bar", Integer),
+            Column("foo", Integer, sa.Computed("bar + 42")),
+        )
+
+        Table(
+            "user",
+            m2,
+            Column("id", Integer, primary_key=True),
+            Column("bar", Integer),
+            Column("foo", Integer),
+        )
+
+        diffs = self._fixture(m1, m2)
+
+        eq_(diffs[0][0][0], "modify_default")
+        eq_(diffs[0][0][2], "user")
+        eq_(diffs[0][0][3], "foo")
+        old = diffs[0][0][-2]
+        new = diffs[0][0][-1]
+
+        is_(new, None)
+        is_true(isinstance(old, sa.DefaultClause))
+
+        if exclusions.against(config, "postgresql"):
+            eq_(str(old.arg.text), "(bar + 42)")
+        elif exclusions.against(config, "oracle"):
+            eq_(str(old.arg.text), '"BAR"+42')

.venv2/Lib/site-packages/alembic/testing/suite/test_autogen_diffs.py

@@ -0,0 +1,273 @@
+from sqlalchemy import BigInteger
+from sqlalchemy import Column
+from sqlalchemy import Integer
+from sqlalchemy import MetaData
+from sqlalchemy import Table
+from sqlalchemy.testing import in_
+
+from ._autogen_fixtures import AutogenFixtureTest
+from ... import testing
+from ...testing import config
+from ...testing import eq_
+from ...testing import is_
+from ...testing import TestBase
+
+
+class AlterColumnTest(AutogenFixtureTest, TestBase):
+    __backend__ = True
+
+    @testing.combinations((True,), (False,))
+    @config.requirements.comments
+    def test_all_existings_filled(self, pk):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table("a", m1, Column("x", Integer, primary_key=pk))
+        Table("a", m2, Column("x", Integer, comment="x", primary_key=pk))
+
+        alter_col = self._assert_alter_col(m1, m2, pk)
+        eq_(alter_col.modify_comment, "x")
+
+    @testing.combinations((True,), (False,))
+    @config.requirements.comments
+    def test_all_existings_filled_in_notnull(self, pk):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table("a", m1, Column("x", Integer, nullable=False, primary_key=pk))
+        Table(
+            "a",
+            m2,
+            Column("x", Integer, nullable=False, comment="x", primary_key=pk),
+        )
+
+        self._assert_alter_col(m1, m2, pk, nullable=False)
+
+    @testing.combinations((True,), (False,))
+    @config.requirements.comments
+    def test_all_existings_filled_in_comment(self, pk):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table("a", m1, Column("x", Integer, comment="old", primary_key=pk))
+        Table("a", m2, Column("x", Integer, comment="new", primary_key=pk))
+
+        alter_col = self._assert_alter_col(m1, m2, pk)
+        eq_(alter_col.existing_comment, "old")
+
+    @testing.combinations((True,), (False,))
+    @config.requirements.comments
+    def test_all_existings_filled_in_server_default(self, pk):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "a", m1, Column("x", Integer, server_default="5", primary_key=pk)
+        )
+        Table(
+            "a",
+            m2,
+            Column(
+                "x", Integer, server_default="5", comment="new", primary_key=pk
+            ),
+        )
+
+        alter_col = self._assert_alter_col(m1, m2, pk)
+        in_("5", alter_col.existing_server_default.arg.text)
+
+    def _assert_alter_col(self, m1, m2, pk, nullable=None):
+        ops = self._fixture(m1, m2, return_ops=True)
+        modify_table = ops.ops[-1]
+        alter_col = modify_table.ops[0]
+
+        if nullable is None:
+            eq_(alter_col.existing_nullable, not pk)
+        else:
+            eq_(alter_col.existing_nullable, nullable)
+        assert alter_col.existing_type._compare_type_affinity(Integer())
+        return alter_col
+
+
+class AutoincrementTest(AutogenFixtureTest, TestBase):
+    __backend__ = True
+    __requires__ = ("integer_subtype_comparisons",)
+
+    def test_alter_column_autoincrement_none(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table("a", m1, Column("x", Integer, nullable=False))
+        Table("a", m2, Column("x", Integer, nullable=True))
+
+        ops = self._fixture(m1, m2, return_ops=True)
+        assert "autoincrement" not in ops.ops[0].ops[0].kw
+
+    def test_alter_column_autoincrement_pk_false(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "a",
+            m1,
+            Column("x", Integer, primary_key=True, autoincrement=False),
+        )
+        Table(
+            "a",
+            m2,
+            Column("x", BigInteger, primary_key=True, autoincrement=False),
+        )
+
+        ops = self._fixture(m1, m2, return_ops=True)
+        is_(ops.ops[0].ops[0].kw["autoincrement"], False)
+
+    def test_alter_column_autoincrement_pk_implicit_true(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table("a", m1, Column("x", Integer, primary_key=True))
+        Table("a", m2, Column("x", BigInteger, primary_key=True))
+
+        ops = self._fixture(m1, m2, return_ops=True)
+        is_(ops.ops[0].ops[0].kw["autoincrement"], True)
+
+    def test_alter_column_autoincrement_pk_explicit_true(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "a", m1, Column("x", Integer, primary_key=True, autoincrement=True)
+        )
+        Table(
+            "a",
+            m2,
+            Column("x", BigInteger, primary_key=True, autoincrement=True),
+        )
+
+        ops = self._fixture(m1, m2, return_ops=True)
+        is_(ops.ops[0].ops[0].kw["autoincrement"], True)
+
+    def test_alter_column_autoincrement_nonpk_false(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "a",
+            m1,
+            Column("id", Integer, primary_key=True),
+            Column("x", Integer, autoincrement=False),
+        )
+        Table(
+            "a",
+            m2,
+            Column("id", Integer, primary_key=True),
+            Column("x", BigInteger, autoincrement=False),
+        )
+
+        ops = self._fixture(m1, m2, return_ops=True)
+        is_(ops.ops[0].ops[0].kw["autoincrement"], False)
+
+    def test_alter_column_autoincrement_nonpk_implicit_false(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "a",
+            m1,
+            Column("id", Integer, primary_key=True),
+            Column("x", Integer),
+        )
+        Table(
+            "a",
+            m2,
+            Column("id", Integer, primary_key=True),
+            Column("x", BigInteger),
+        )
+
+        ops = self._fixture(m1, m2, return_ops=True)
+        assert "autoincrement" not in ops.ops[0].ops[0].kw
+
+    def test_alter_column_autoincrement_nonpk_explicit_true(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "a",
+            m1,
+            Column("id", Integer, primary_key=True, autoincrement=False),
+            Column("x", Integer, autoincrement=True),
+        )
+        Table(
+            "a",
+            m2,
+            Column("id", Integer, primary_key=True, autoincrement=False),
+            Column("x", BigInteger, autoincrement=True),
+        )
+
+        ops = self._fixture(m1, m2, return_ops=True)
+        is_(ops.ops[0].ops[0].kw["autoincrement"], True)
+
+    def test_alter_column_autoincrement_compositepk_false(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "a",
+            m1,
+            Column("id", Integer, primary_key=True),
+            Column("x", Integer, primary_key=True, autoincrement=False),
+        )
+        Table(
+            "a",
+            m2,
+            Column("id", Integer, primary_key=True),
+            Column("x", BigInteger, primary_key=True, autoincrement=False),
+        )
+
+        ops = self._fixture(m1, m2, return_ops=True)
+        is_(ops.ops[0].ops[0].kw["autoincrement"], False)
+
+    def test_alter_column_autoincrement_compositepk_implicit_false(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "a",
+            m1,
+            Column("id", Integer, primary_key=True),
+            Column("x", Integer, primary_key=True),
+        )
+        Table(
+            "a",
+            m2,
+            Column("id", Integer, primary_key=True),
+            Column("x", BigInteger, primary_key=True),
+        )
+
+        ops = self._fixture(m1, m2, return_ops=True)
+        assert "autoincrement" not in ops.ops[0].ops[0].kw
+
+    @config.requirements.autoincrement_on_composite_pk
+    def test_alter_column_autoincrement_compositepk_explicit_true(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "a",
+            m1,
+            Column("id", Integer, primary_key=True, autoincrement=False),
+            Column("x", Integer, primary_key=True, autoincrement=True),
+            # on SQLA 1.0 and earlier, this being present
+            # trips the "add KEY for the primary key" so that the
+            # AUTO_INCREMENT keyword is accepted by MySQL.  SQLA 1.1 and
+            # greater the columns are just reorganized.
+            mysql_engine="InnoDB",
+        )
+        Table(
+            "a",
+            m2,
+            Column("id", Integer, primary_key=True, autoincrement=False),
+            Column("x", BigInteger, primary_key=True, autoincrement=True),
+        )
+
+        ops = self._fixture(m1, m2, return_ops=True)
+        is_(ops.ops[0].ops[0].kw["autoincrement"], True)

.venv2/Lib/site-packages/alembic/testing/suite/test_autogen_identity.py

@@ -0,0 +1,226 @@
+import sqlalchemy as sa
+from sqlalchemy import Column
+from sqlalchemy import Integer
+from sqlalchemy import MetaData
+from sqlalchemy import Table
+
+from alembic.util import sqla_compat
+from ._autogen_fixtures import AutogenFixtureTest
+from ... import testing
+from ...testing import config
+from ...testing import eq_
+from ...testing import is_true
+from ...testing import TestBase
+
+
+class AutogenerateIdentityTest(AutogenFixtureTest, TestBase):
+    __requires__ = ("identity_columns",)
+    __backend__ = True
+
+    def test_add_identity_column(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table("user", m1, Column("other", sa.Text))
+
+        Table(
+            "user",
+            m2,
+            Column("other", sa.Text),
+            Column(
+                "id",
+                Integer,
+                sa.Identity(start=5, increment=7),
+                primary_key=True,
+            ),
+        )
+
+        diffs = self._fixture(m1, m2)
+
+        eq_(diffs[0][0], "add_column")
+        eq_(diffs[0][2], "user")
+        eq_(diffs[0][3].name, "id")
+        i = diffs[0][3].identity
+
+        is_true(isinstance(i, sa.Identity))
+        eq_(i.start, 5)
+        eq_(i.increment, 7)
+
+    def test_remove_identity_column(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "user",
+            m1,
+            Column(
+                "id",
+                Integer,
+                sa.Identity(start=2, increment=3),
+                primary_key=True,
+            ),
+        )
+
+        Table("user", m2)
+
+        diffs = self._fixture(m1, m2)
+
+        eq_(diffs[0][0], "remove_column")
+        eq_(diffs[0][2], "user")
+        c = diffs[0][3]
+        eq_(c.name, "id")
+
+        is_true(isinstance(c.identity, sa.Identity))
+        eq_(c.identity.start, 2)
+        eq_(c.identity.increment, 3)
+
+    def test_no_change_identity_column(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        for m in (m1, m2):
+            id_ = sa.Identity(start=2)
+            Table("user", m, Column("id", Integer, id_))
+
+        diffs = self._fixture(m1, m2)
+
+        eq_(diffs, [])
+
+    def test_dialect_kwargs_changes(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        if sqla_compat.identity_has_dialect_kwargs:
+            args = {"oracle_on_null": True, "oracle_order": True}
+        else:
+            args = {"on_null": True, "order": True}
+
+        Table("user", m1, Column("id", Integer, sa.Identity(start=2)))
+        id_ = sa.Identity(start=2, **args)
+        Table("user", m2, Column("id", Integer, id_))
+
+        diffs = self._fixture(m1, m2)
+        if config.db.name == "oracle":
+            is_true(len(diffs), 1)
+            eq_(diffs[0][0][0], "modify_default")
+        else:
+            eq_(diffs, [])
+
+    @testing.combinations(
+        (None, dict(start=2)),
+        (dict(start=2), None),
+        (dict(start=2), dict(start=2, increment=7)),
+        (dict(always=False), dict(always=True)),
+        (
+            dict(start=1, minvalue=0, maxvalue=100, cycle=True),
+            dict(start=1, minvalue=0, maxvalue=100, cycle=False),
+        ),
+        (
+            dict(start=10, increment=3, maxvalue=9999),
+            dict(start=10, increment=1, maxvalue=3333),
+        ),
+    )
+    @config.requirements.identity_columns_alter
+    def test_change_identity(self, before, after):
+        arg_before = (sa.Identity(**before),) if before else ()
+        arg_after = (sa.Identity(**after),) if after else ()
+
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "user",
+            m1,
+            Column("id", Integer, *arg_before),
+            Column("other", sa.Text),
+        )
+
+        Table(
+            "user",
+            m2,
+            Column("id", Integer, *arg_after),
+            Column("other", sa.Text),
+        )
+
+        diffs = self._fixture(m1, m2)
+
+        eq_(len(diffs[0]), 1)
+        diffs = diffs[0][0]
+        eq_(diffs[0], "modify_default")
+        eq_(diffs[2], "user")
+        eq_(diffs[3], "id")
+        old = diffs[5]
+        new = diffs[6]
+
+        def check(kw, idt):
+            if kw:
+                is_true(isinstance(idt, sa.Identity))
+                for k, v in kw.items():
+                    eq_(getattr(idt, k), v)
+            else:
+                is_true(idt in (None, False))
+
+        check(before, old)
+        check(after, new)
+
+    def test_add_identity_to_column(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "user",
+            m1,
+            Column("id", Integer),
+            Column("other", sa.Text),
+        )
+
+        Table(
+            "user",
+            m2,
+            Column("id", Integer, sa.Identity(start=2, maxvalue=1000)),
+            Column("other", sa.Text),
+        )
+
+        diffs = self._fixture(m1, m2)
+
+        eq_(len(diffs[0]), 1)
+        diffs = diffs[0][0]
+        eq_(diffs[0], "modify_default")
+        eq_(diffs[2], "user")
+        eq_(diffs[3], "id")
+        eq_(diffs[5], None)
+        added = diffs[6]
+
+        is_true(isinstance(added, sa.Identity))
+        eq_(added.start, 2)
+        eq_(added.maxvalue, 1000)
+
+    def test_remove_identity_from_column(self):
+        m1 = MetaData()
+        m2 = MetaData()
+
+        Table(
+            "user",
+            m1,
+            Column("id", Integer, sa.Identity(start=2, maxvalue=1000)),
+            Column("other", sa.Text),
+        )
+
+        Table(
+            "user",
+            m2,
+            Column("id", Integer),
+            Column("other", sa.Text),
+        )
+
+        diffs = self._fixture(m1, m2)
+
+        eq_(len(diffs[0]), 1)
+        diffs = diffs[0][0]
+        eq_(diffs[0], "modify_default")
+        eq_(diffs[2], "user")
+        eq_(diffs[3], "id")
+        eq_(diffs[6], None)
+        removed = diffs[5]
+
+        is_true(isinstance(removed, sa.Identity))

.venv2/Lib/site-packages/alembic/testing/suite/test_environment.py

@@ -0,0 +1,364 @@
+import io
+
+from ...migration import MigrationContext
+from ...testing import assert_raises
+from ...testing import config
+from ...testing import eq_
+from ...testing import is_
+from ...testing import is_false
+from ...testing import is_not_
+from ...testing import is_true
+from ...testing import ne_
+from ...testing.fixtures import TestBase
+
+
+class MigrationTransactionTest(TestBase):
+    __backend__ = True
+
+    conn = None
+
+    def _fixture(self, opts):
+        self.conn = conn = config.db.connect()
+
+        if opts.get("as_sql", False):
+            self.context = MigrationContext.configure(
+                dialect=conn.dialect, opts=opts
+            )
+            self.context.output_buffer = (
+                self.context.impl.output_buffer
+            ) = io.StringIO()
+        else:
+            self.context = MigrationContext.configure(
+                connection=conn, opts=opts
+            )
+        return self.context
+
+    def teardown_method(self):
+        if self.conn:
+            self.conn.close()
+
+    def test_proxy_transaction_rollback(self):
+        context = self._fixture(
+            {"transaction_per_migration": True, "transactional_ddl": True}
+        )
+
+        is_false(self.conn.in_transaction())
+        proxy = context.begin_transaction(_per_migration=True)
+        is_true(self.conn.in_transaction())
+        proxy.rollback()
+        is_false(self.conn.in_transaction())
+
+    def test_proxy_transaction_commit(self):
+        context = self._fixture(
+            {"transaction_per_migration": True, "transactional_ddl": True}
+        )
+        proxy = context.begin_transaction(_per_migration=True)
+        is_true(self.conn.in_transaction())
+        proxy.commit()
+        is_false(self.conn.in_transaction())
+
+    def test_proxy_transaction_contextmanager_commit(self):
+        context = self._fixture(
+            {"transaction_per_migration": True, "transactional_ddl": True}
+        )
+        proxy = context.begin_transaction(_per_migration=True)
+        is_true(self.conn.in_transaction())
+        with proxy:
+            pass
+        is_false(self.conn.in_transaction())
+
+    def test_proxy_transaction_contextmanager_rollback(self):
+        context = self._fixture(
+            {"transaction_per_migration": True, "transactional_ddl": True}
+        )
+        proxy = context.begin_transaction(_per_migration=True)
+        is_true(self.conn.in_transaction())
+
+        def go():
+            with proxy:
+                raise Exception("hi")
+
+        assert_raises(Exception, go)
+        is_false(self.conn.in_transaction())
+
+    def test_proxy_transaction_contextmanager_explicit_rollback(self):
+        context = self._fixture(
+            {"transaction_per_migration": True, "transactional_ddl": True}
+        )
+        proxy = context.begin_transaction(_per_migration=True)
+        is_true(self.conn.in_transaction())
+
+        with proxy:
+            is_true(self.conn.in_transaction())
+            proxy.rollback()
+            is_false(self.conn.in_transaction())
+
+        is_false(self.conn.in_transaction())
+
+    def test_proxy_transaction_contextmanager_explicit_commit(self):
+        context = self._fixture(
+            {"transaction_per_migration": True, "transactional_ddl": True}
+        )
+        proxy = context.begin_transaction(_per_migration=True)
+        is_true(self.conn.in_transaction())
+
+        with proxy:
+            is_true(self.conn.in_transaction())
+            proxy.commit()
+            is_false(self.conn.in_transaction())
+
+        is_false(self.conn.in_transaction())
+
+    def test_transaction_per_migration_transactional_ddl(self):
+        context = self._fixture(
+            {"transaction_per_migration": True, "transactional_ddl": True}
+        )
+
+        is_false(self.conn.in_transaction())
+
+        with context.begin_transaction():
+            is_false(self.conn.in_transaction())
+            with context.begin_transaction(_per_migration=True):
+                is_true(self.conn.in_transaction())
+
+            is_false(self.conn.in_transaction())
+        is_false(self.conn.in_transaction())
+
+    def test_transaction_per_migration_non_transactional_ddl(self):
+        context = self._fixture(
+            {"transaction_per_migration": True, "transactional_ddl": False}
+        )
+
+        is_false(self.conn.in_transaction())
+
+        with context.begin_transaction():
+            is_false(self.conn.in_transaction())
+            with context.begin_transaction(_per_migration=True):
+                is_true(self.conn.in_transaction())
+
+            is_false(self.conn.in_transaction())
+        is_false(self.conn.in_transaction())
+
+    def test_transaction_per_all_transactional_ddl(self):
+        context = self._fixture({"transactional_ddl": True})
+
+        is_false(self.conn.in_transaction())
+
+        with context.begin_transaction():
+            is_true(self.conn.in_transaction())
+            with context.begin_transaction(_per_migration=True):
+                is_true(self.conn.in_transaction())
+
+            is_true(self.conn.in_transaction())
+        is_false(self.conn.in_transaction())
+
+    def test_transaction_per_all_non_transactional_ddl(self):
+        context = self._fixture({"transactional_ddl": False})
+
+        is_false(self.conn.in_transaction())
+
+        with context.begin_transaction():
+            is_false(self.conn.in_transaction())
+            with context.begin_transaction(_per_migration=True):
+                is_true(self.conn.in_transaction())
+
+            is_false(self.conn.in_transaction())
+        is_false(self.conn.in_transaction())
+
+    def test_transaction_per_all_sqlmode(self):
+        context = self._fixture({"as_sql": True})
+
+        context.execute("step 1")
+        with context.begin_transaction():
+            context.execute("step 2")
+            with context.begin_transaction(_per_migration=True):
+                context.execute("step 3")
+
+            context.execute("step 4")
+        context.execute("step 5")
+
+        if context.impl.transactional_ddl:
+            self._assert_impl_steps(
+                "step 1",
+                "BEGIN",
+                "step 2",
+                "step 3",
+                "step 4",
+                "COMMIT",
+                "step 5",
+            )
+        else:
+            self._assert_impl_steps(
+                "step 1", "step 2", "step 3", "step 4", "step 5"
+            )
+
+    def test_transaction_per_migration_sqlmode(self):
+        context = self._fixture(
+            {"as_sql": True, "transaction_per_migration": True}
+        )
+
+        context.execute("step 1")
+        with context.begin_transaction():
+            context.execute("step 2")
+            with context.begin_transaction(_per_migration=True):
+                context.execute("step 3")
+
+            context.execute("step 4")
+        context.execute("step 5")
+
+        if context.impl.transactional_ddl:
+            self._assert_impl_steps(
+                "step 1",
+                "step 2",
+                "BEGIN",
+                "step 3",
+                "COMMIT",
+                "step 4",
+                "step 5",
+            )
+        else:
+            self._assert_impl_steps(
+                "step 1", "step 2", "step 3", "step 4", "step 5"
+            )
+
+    @config.requirements.autocommit_isolation
+    def test_autocommit_block(self):
+        context = self._fixture({"transaction_per_migration": True})
+
+        is_false(self.conn.in_transaction())
+
+        with context.begin_transaction():
+            is_false(self.conn.in_transaction())
+            with context.begin_transaction(_per_migration=True):
+                is_true(self.conn.in_transaction())
+
+                with context.autocommit_block():
+                    # in 1.x, self.conn is separate due to the
+                    # execution_options call.  however for future they are the
+                    # same connection and there is a "transaction" block
+                    # despite autocommit
+                    if self.is_sqlalchemy_future:
+                        is_(context.connection, self.conn)
+                    else:
+                        is_not_(context.connection, self.conn)
+                        is_false(self.conn.in_transaction())
+
+                    eq_(
+                        context.connection._execution_options[
+                            "isolation_level"
+                        ],
+                        "AUTOCOMMIT",
+                    )
+
+                ne_(
+                    context.connection._execution_options.get(
+                        "isolation_level", None
+                    ),
+                    "AUTOCOMMIT",
+                )
+                is_true(self.conn.in_transaction())
+
+            is_false(self.conn.in_transaction())
+        is_false(self.conn.in_transaction())
+
+    @config.requirements.autocommit_isolation
+    def test_autocommit_block_no_transaction(self):
+        context = self._fixture({"transaction_per_migration": True})
+
+        is_false(self.conn.in_transaction())
+
+        with context.autocommit_block():
+            is_true(context.connection.in_transaction())
+
+            # in 1.x, self.conn is separate due to the execution_options
+            # call.  however for future they are the same connection and there
+            # is a "transaction" block despite autocommit
+            if self.is_sqlalchemy_future:
+                is_(context.connection, self.conn)
+            else:
+                is_not_(context.connection, self.conn)
+                is_false(self.conn.in_transaction())
+
+            eq_(
+                context.connection._execution_options["isolation_level"],
+                "AUTOCOMMIT",
+            )
+
+        ne_(
+            context.connection._execution_options.get("isolation_level", None),
+            "AUTOCOMMIT",
+        )
+
+        is_false(self.conn.in_transaction())
+
+    def test_autocommit_block_transactional_ddl_sqlmode(self):
+        context = self._fixture(
+            {
+                "transaction_per_migration": True,
+                "transactional_ddl": True,
+                "as_sql": True,
+            }
+        )
+
+        with context.begin_transaction():
+            context.execute("step 1")
+            with context.begin_transaction(_per_migration=True):
+                context.execute("step 2")
+
+                with context.autocommit_block():
+                    context.execute("step 3")
+
+                context.execute("step 4")
+
+            context.execute("step 5")
+
+        self._assert_impl_steps(
+            "step 1",
+            "BEGIN",
+            "step 2",
+            "COMMIT",
+            "step 3",
+            "BEGIN",
+            "step 4",
+            "COMMIT",
+            "step 5",
+        )
+
+    def test_autocommit_block_nontransactional_ddl_sqlmode(self):
+        context = self._fixture(
+            {
+                "transaction_per_migration": True,
+                "transactional_ddl": False,
+                "as_sql": True,
+            }
+        )
+
+        with context.begin_transaction():
+            context.execute("step 1")
+            with context.begin_transaction(_per_migration=True):
+                context.execute("step 2")
+
+                with context.autocommit_block():
+                    context.execute("step 3")
+
+                context.execute("step 4")
+
+            context.execute("step 5")
+
+        self._assert_impl_steps(
+            "step 1", "step 2", "step 3", "step 4", "step 5"
+        )
+
+    def _assert_impl_steps(self, *steps):
+        to_check = self.context.output_buffer.getvalue()
+
+        self.context.impl.output_buffer = buf = io.StringIO()
+        for step in steps:
+            if step == "BEGIN":
+                self.context.impl.emit_begin()
+            elif step == "COMMIT":
+                self.context.impl.emit_commit()
+            else:
+                self.context.impl._exec(step)
+
+        eq_(to_check, buf.getvalue())

.venv2/Lib/site-packages/alembic/testing/suite/test_op.py

@@ -0,0 +1,42 @@
+"""Test against the builders in the op.* module."""
+
+from sqlalchemy import Column
+from sqlalchemy import event
+from sqlalchemy import Integer
+from sqlalchemy import String
+from sqlalchemy import Table
+from sqlalchemy.sql import text
+
+from ...testing.fixtures import AlterColRoundTripFixture
+from ...testing.fixtures import TestBase
+
+
+@event.listens_for(Table, "after_parent_attach")
+def _add_cols(table, metadata):
+    if table.name == "tbl_with_auto_appended_column":
+        table.append_column(Column("bat", Integer))
+
+
+class BackendAlterColumnTest(AlterColRoundTripFixture, TestBase):
+    __backend__ = True
+
+    def test_rename_column(self):
+        self._run_alter_col({}, {"name": "newname"})
+
+    def test_modify_type_int_str(self):
+        self._run_alter_col({"type": Integer()}, {"type": String(50)})
+
+    def test_add_server_default_int(self):
+        self._run_alter_col({"type": Integer}, {"server_default": text("5")})
+
+    def test_modify_server_default_int(self):
+        self._run_alter_col(
+            {"type": Integer, "server_default": text("2")},
+            {"server_default": text("5")},
+        )
+
+    def test_modify_nullable_to_non(self):
+        self._run_alter_col({}, {"nullable": False})
+
+    def test_modify_non_nullable_to_nullable(self):
+        self._run_alter_col({"nullable": False}, {"nullable": True})

.venv2/Lib/site-packages/alembic/testing/util.py

@@ -0,0 +1,126 @@
+# testing/util.py
+# Copyright (C) 2005-2019 the SQLAlchemy authors and contributors
+# <see AUTHORS file>
+#
+# This module is part of SQLAlchemy and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+from __future__ import annotations
+
+import types
+from typing import Union
+
+from sqlalchemy.util import inspect_getfullargspec
+
+from ..util import sqla_2
+
+
+def flag_combinations(*combinations):
+    """A facade around @testing.combinations() oriented towards boolean
+    keyword-based arguments.
+
+    Basically generates a nice looking identifier based on the keywords
+    and also sets up the argument names.
+
+    E.g.::
+
+        @testing.flag_combinations(
+            dict(lazy=False, passive=False),
+            dict(lazy=True, passive=False),
+            dict(lazy=False, passive=True),
+            dict(lazy=False, passive=True, raiseload=True),
+        )
+
+
+    would result in::
+
+        @testing.combinations(
+            ('', False, False, False),
+            ('lazy', True, False, False),
+            ('lazy_passive', True, True, False),
+            ('lazy_passive', True, True, True),
+            id_='iaaa',
+            argnames='lazy,passive,raiseload'
+        )
+
+    """
+    from sqlalchemy.testing import config
+
+    keys = set()
+
+    for d in combinations:
+        keys.update(d)
+
+    keys = sorted(keys)
+
+    return config.combinations(
+        *[
+            ("_".join(k for k in keys if d.get(k, False)),)
+            + tuple(d.get(k, False) for k in keys)
+            for d in combinations
+        ],
+        id_="i" + ("a" * len(keys)),
+        argnames=",".join(keys),
+    )
+
+
+def resolve_lambda(__fn, **kw):
+    """Given a no-arg lambda and a namespace, return a new lambda that
+    has all the values filled in.
+
+    This is used so that we can have module-level fixtures that
+    refer to instance-level variables using lambdas.
+
+    """
+
+    pos_args = inspect_getfullargspec(__fn)[0]
+    pass_pos_args = {arg: kw.pop(arg) for arg in pos_args}
+    glb = dict(__fn.__globals__)
+    glb.update(kw)
+    new_fn = types.FunctionType(__fn.__code__, glb)
+    return new_fn(**pass_pos_args)
+
+
+def metadata_fixture(ddl="function"):
+    """Provide MetaData for a pytest fixture."""
+
+    from sqlalchemy.testing import config
+    from . import fixture_functions
+
+    def decorate(fn):
+        def run_ddl(self):
+            from sqlalchemy import schema
+
+            metadata = self.metadata = schema.MetaData()
+            try:
+                result = fn(self, metadata)
+                metadata.create_all(config.db)
+                # TODO:
+                # somehow get a per-function dml erase fixture here
+                yield result
+            finally:
+                metadata.drop_all(config.db)
+
+        return fixture_functions.fixture(scope=ddl)(run_ddl)
+
+    return decorate
+
+
+def _safe_int(value: str) -> Union[int, str]:
+    try:
+        return int(value)
+    except:
+        return value
+
+
+def testing_engine(url=None, options=None, future=False):
+    from sqlalchemy.testing import config
+    from sqlalchemy.testing.engines import testing_engine
+
+    if not future:
+        future = getattr(config._current.options, "future_engine", False)
+
+    if not sqla_2:
+        kw = {"future": future} if future else {}
+    else:
+        kw = {}
+    return testing_engine(url, options, **kw)

.venv2/Lib/site-packages/alembic/testing/warnings.py

@@ -0,0 +1,40 @@
+# testing/warnings.py
+# Copyright (C) 2005-2021 the SQLAlchemy authors and contributors
+# <see AUTHORS file>
+#
+# This module is part of SQLAlchemy and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+
+import warnings
+
+from sqlalchemy import exc as sa_exc
+
+from ..util import sqla_14
+
+
+def setup_filters():
+    """Set global warning behavior for the test suite."""
+
+    warnings.resetwarnings()
+
+    warnings.filterwarnings("error", category=sa_exc.SADeprecationWarning)
+    warnings.filterwarnings("error", category=sa_exc.SAWarning)
+
+    # some selected deprecations...
+    warnings.filterwarnings("error", category=DeprecationWarning)
+    if not sqla_14:
+        # 1.3 uses pkg_resources in PluginLoader
+        warnings.filterwarnings(
+            "ignore",
+            "pkg_resources is deprecated as an API",
+            DeprecationWarning,
+        )
+    try:
+        import pytest
+    except ImportError:
+        pass
+    else:
+        warnings.filterwarnings(
+            "once", category=pytest.PytestDeprecationWarning
+        )

.venv2/Lib/site-packages/alembic/util/__init__.py

@@ -0,0 +1,35 @@
+from .editor import open_in_editor as open_in_editor
+from .exc import AutogenerateDiffsDetected as AutogenerateDiffsDetected
+from .exc import CommandError as CommandError
+from .langhelpers import _with_legacy_names as _with_legacy_names
+from .langhelpers import asbool as asbool
+from .langhelpers import dedupe_tuple as dedupe_tuple
+from .langhelpers import Dispatcher as Dispatcher
+from .langhelpers import EMPTY_DICT as EMPTY_DICT
+from .langhelpers import immutabledict as immutabledict
+from .langhelpers import memoized_property as memoized_property
+from .langhelpers import ModuleClsProxy as ModuleClsProxy
+from .langhelpers import not_none as not_none
+from .langhelpers import rev_id as rev_id
+from .langhelpers import to_list as to_list
+from .langhelpers import to_tuple as to_tuple
+from .langhelpers import unique_list as unique_list
+from .messaging import err as err
+from .messaging import format_as_comma as format_as_comma
+from .messaging import msg as msg
+from .messaging import obfuscate_url_pw as obfuscate_url_pw
+from .messaging import status as status
+from .messaging import warn as warn
+from .messaging import write_outstream as write_outstream
+from .pyfiles import coerce_resource_to_filename as coerce_resource_to_filename
+from .pyfiles import load_python_file as load_python_file
+from .pyfiles import pyc_file_from_path as pyc_file_from_path
+from .pyfiles import template_to_file as template_to_file
+from .sqla_compat import has_computed as has_computed
+from .sqla_compat import sqla_13 as sqla_13
+from .sqla_compat import sqla_14 as sqla_14
+from .sqla_compat import sqla_2 as sqla_2
+
+
+if not sqla_13:
+    raise CommandError("SQLAlchemy 1.3.0 or greater is required.")

.venv2/Lib/site-packages/alembic/util/compat.py

@@ -0,0 +1,89 @@
+# mypy: no-warn-unused-ignores
+
+from __future__ import annotations
+
+from configparser import ConfigParser
+import io
+import os
+import sys
+import typing
+from typing import Any
+from typing import List
+from typing import Optional
+from typing import Sequence
+from typing import Union
+
+if True:
+    # zimports hack for too-long names
+    from sqlalchemy.util import (  # noqa: F401
+        inspect_getfullargspec as inspect_getfullargspec,
+    )
+    from sqlalchemy.util.compat import (  # noqa: F401
+        inspect_formatargspec as inspect_formatargspec,
+    )
+
+is_posix = os.name == "posix"
+
+py311 = sys.version_info >= (3, 11)
+py310 = sys.version_info >= (3, 10)
+py39 = sys.version_info >= (3, 9)
+
+
+# produce a wrapper that allows encoded text to stream
+# into a given buffer, but doesn't close it.
+# not sure of a more idiomatic approach to this.
+class EncodedIO(io.TextIOWrapper):
+    def close(self) -> None:
+        pass
+
+
+if py39:
+    from importlib import resources as _resources
+
+    importlib_resources = _resources
+    from importlib import metadata as _metadata
+
+    importlib_metadata = _metadata
+    from importlib.metadata import EntryPoint as EntryPoint
+else:
+    import importlib_resources  # type:ignore # noqa
+    import importlib_metadata  # type:ignore # noqa
+    from importlib_metadata import EntryPoint  # type:ignore # noqa
+
+
+def importlib_metadata_get(group: str) -> Sequence[EntryPoint]:
+    ep = importlib_metadata.entry_points()
+    if hasattr(ep, "select"):
+        return ep.select(group=group)
+    else:
+        return ep.get(group, ())  # type: ignore
+
+
+def formatannotation_fwdref(
+    annotation: Any, base_module: Optional[Any] = None
+) -> str:
+    """vendored from python 3.7"""
+    # copied over _formatannotation from sqlalchemy 2.0
+
+    if isinstance(annotation, str):
+        return annotation
+
+    if getattr(annotation, "__module__", None) == "typing":
+        return repr(annotation).replace("typing.", "").replace("~", "")
+    if isinstance(annotation, type):
+        if annotation.__module__ in ("builtins", base_module):
+            return repr(annotation.__qualname__)
+        return annotation.__module__ + "." + annotation.__qualname__
+    elif isinstance(annotation, typing.TypeVar):
+        return repr(annotation).replace("~", "")
+    return repr(annotation).replace("~", "")
+
+
+def read_config_parser(
+    file_config: ConfigParser,
+    file_argument: Sequence[Union[str, os.PathLike[str]]],
+) -> List[str]:
+    if py310:
+        return file_config.read(file_argument, encoding="locale")
+    else:
+        return file_config.read(file_argument)

.venv2/Lib/site-packages/alembic/util/editor.py

@@ -0,0 +1,81 @@
+from __future__ import annotations
+
+import os
+from os.path import exists
+from os.path import join
+from os.path import splitext
+from subprocess import check_call
+from typing import Dict
+from typing import List
+from typing import Mapping
+from typing import Optional
+
+from .compat import is_posix
+from .exc import CommandError
+
+
+def open_in_editor(
+    filename: str, environ: Optional[Dict[str, str]] = None
+) -> None:
+    """
+    Opens the given file in a text editor. If the environment variable
+    ``EDITOR`` is set, this is taken as preference.
+
+    Otherwise, a list of commonly installed editors is tried.
+
+    If no editor matches, an :py:exc:`OSError` is raised.
+
+    :param filename: The filename to open. Will be passed  verbatim to the
+        editor command.
+    :param environ: An optional drop-in replacement for ``os.environ``. Used
+        mainly for testing.
+    """
+    env = os.environ if environ is None else environ
+    try:
+        editor = _find_editor(env)
+        check_call([editor, filename])
+    except Exception as exc:
+        raise CommandError("Error executing editor (%s)" % (exc,)) from exc
+
+
+def _find_editor(environ: Mapping[str, str]) -> str:
+    candidates = _default_editors()
+    for i, var in enumerate(("EDITOR", "VISUAL")):
+        if var in environ:
+            user_choice = environ[var]
+            if exists(user_choice):
+                return user_choice
+            if os.sep not in user_choice:
+                candidates.insert(i, user_choice)
+
+    for candidate in candidates:
+        path = _find_executable(candidate, environ)
+        if path is not None:
+            return path
+    raise OSError(
+        "No suitable editor found. Please set the "
+        '"EDITOR" or "VISUAL" environment variables'
+    )
+
+
+def _find_executable(
+    candidate: str, environ: Mapping[str, str]
+) -> Optional[str]:
+    # Assuming this is on the PATH, we need to determine it's absolute
+    # location. Otherwise, ``check_call`` will fail
+    if not is_posix and splitext(candidate)[1] != ".exe":
+        candidate += ".exe"
+    for path in environ.get("PATH", "").split(os.pathsep):
+        value = join(path, candidate)
+        if exists(value):
+            return value
+    return None
+
+
+def _default_editors() -> List[str]:
+    # Look for an editor. Prefer the user's choice by env-var, fall back to
+    # most commonly installed editor (nano/vim)
+    if is_posix:
+        return ["sensible-editor", "editor", "nano", "vim", "code"]
+    else:
+        return ["code.exe", "notepad++.exe", "notepad.exe"]

.venv2/Lib/site-packages/alembic/util/exc.py

@@ -0,0 +1,6 @@
+class CommandError(Exception):
+    pass
+
+
+class AutogenerateDiffsDetected(CommandError):
+    pass

.venv2/Lib/site-packages/alembic/util/langhelpers.py

@@ -0,0 +1,335 @@
+from __future__ import annotations
+
+import collections
+from collections.abc import Iterable
+import textwrap
+from typing import Any
+from typing import Callable
+from typing import cast
+from typing import Dict
+from typing import List
+from typing import Mapping
+from typing import MutableMapping
+from typing import NoReturn
+from typing import Optional
+from typing import overload
+from typing import Sequence
+from typing import Set
+from typing import Tuple
+from typing import Type
+from typing import TYPE_CHECKING
+from typing import TypeVar
+from typing import Union
+import uuid
+import warnings
+
+from sqlalchemy.util import asbool as asbool  # noqa: F401
+from sqlalchemy.util import immutabledict as immutabledict  # noqa: F401
+from sqlalchemy.util import to_list as to_list  # noqa: F401
+from sqlalchemy.util import unique_list as unique_list
+
+from .compat import inspect_getfullargspec
+
+if True:
+    # zimports workaround :(
+    from sqlalchemy.util import (  # noqa: F401
+        memoized_property as memoized_property,
+    )
+
+
+EMPTY_DICT: Mapping[Any, Any] = immutabledict()
+_T = TypeVar("_T", bound=Any)
+
+_C = TypeVar("_C", bound=Callable[..., Any])
+
+
+class _ModuleClsMeta(type):
+    def __setattr__(cls, key: str, value: Callable[..., Any]) -> None:
+        super().__setattr__(key, value)
+        cls._update_module_proxies(key)  # type: ignore
+
+
+class ModuleClsProxy(metaclass=_ModuleClsMeta):
+    """Create module level proxy functions for the
+    methods on a given class.
+
+    The functions will have a compatible signature
+    as the methods.
+
+    """
+
+    _setups: Dict[
+        Type[Any],
+        Tuple[
+            Set[str],
+            List[Tuple[MutableMapping[str, Any], MutableMapping[str, Any]]],
+        ],
+    ] = collections.defaultdict(lambda: (set(), []))
+
+    @classmethod
+    def _update_module_proxies(cls, name: str) -> None:
+        attr_names, modules = cls._setups[cls]
+        for globals_, locals_ in modules:
+            cls._add_proxied_attribute(name, globals_, locals_, attr_names)
+
+    def _install_proxy(self) -> None:
+        attr_names, modules = self._setups[self.__class__]
+        for globals_, locals_ in modules:
+            globals_["_proxy"] = self
+            for attr_name in attr_names:
+                globals_[attr_name] = getattr(self, attr_name)
+
+    def _remove_proxy(self) -> None:
+        attr_names, modules = self._setups[self.__class__]
+        for globals_, locals_ in modules:
+            globals_["_proxy"] = None
+            for attr_name in attr_names:
+                del globals_[attr_name]
+
+    @classmethod
+    def create_module_class_proxy(
+        cls,
+        globals_: MutableMapping[str, Any],
+        locals_: MutableMapping[str, Any],
+    ) -> None:
+        attr_names, modules = cls._setups[cls]
+        modules.append((globals_, locals_))
+        cls._setup_proxy(globals_, locals_, attr_names)
+
+    @classmethod
+    def _setup_proxy(
+        cls,
+        globals_: MutableMapping[str, Any],
+        locals_: MutableMapping[str, Any],
+        attr_names: Set[str],
+    ) -> None:
+        for methname in dir(cls):
+            cls._add_proxied_attribute(methname, globals_, locals_, attr_names)
+
+    @classmethod
+    def _add_proxied_attribute(
+        cls,
+        methname: str,
+        globals_: MutableMapping[str, Any],
+        locals_: MutableMapping[str, Any],
+        attr_names: Set[str],
+    ) -> None:
+        if not methname.startswith("_"):
+            meth = getattr(cls, methname)
+            if callable(meth):
+                locals_[methname] = cls._create_method_proxy(
+                    methname, globals_, locals_
+                )
+            else:
+                attr_names.add(methname)
+
+    @classmethod
+    def _create_method_proxy(
+        cls,
+        name: str,
+        globals_: MutableMapping[str, Any],
+        locals_: MutableMapping[str, Any],
+    ) -> Callable[..., Any]:
+        fn = getattr(cls, name)
+
+        def _name_error(name: str, from_: Exception) -> NoReturn:
+            raise NameError(
+                "Can't invoke function '%s', as the proxy object has "
+                "not yet been "
+                "established for the Alembic '%s' class.  "
+                "Try placing this code inside a callable."
+                % (name, cls.__name__)
+            ) from from_
+
+        globals_["_name_error"] = _name_error
+
+        translations = getattr(fn, "_legacy_translations", [])
+        if translations:
+            spec = inspect_getfullargspec(fn)
+            if spec[0] and spec[0][0] == "self":
+                spec[0].pop(0)
+
+            outer_args = inner_args = "*args, **kw"
+            translate_str = "args, kw = _translate(%r, %r, %r, args, kw)" % (
+                fn.__name__,
+                tuple(spec),
+                translations,
+            )
+
+            def translate(
+                fn_name: str, spec: Any, translations: Any, args: Any, kw: Any
+            ) -> Any:
+                return_kw = {}
+                return_args = []
+
+                for oldname, newname in translations:
+                    if oldname in kw:
+                        warnings.warn(
+                            "Argument %r is now named %r "
+                            "for method %s()." % (oldname, newname, fn_name)
+                        )
+                        return_kw[newname] = kw.pop(oldname)
+                return_kw.update(kw)
+
+                args = list(args)
+                if spec[3]:
+                    pos_only = spec[0][: -len(spec[3])]
+                else:
+                    pos_only = spec[0]
+                for arg in pos_only:
+                    if arg not in return_kw:
+                        try:
+                            return_args.append(args.pop(0))
+                        except IndexError:
+                            raise TypeError(
+                                "missing required positional argument: %s"
+                                % arg
+                            )
+                return_args.extend(args)
+
+                return return_args, return_kw
+
+            globals_["_translate"] = translate
+        else:
+            outer_args = "*args, **kw"
+            inner_args = "*args, **kw"
+            translate_str = ""
+
+        func_text = textwrap.dedent(
+            """\
+        def %(name)s(%(args)s):
+            %(doc)r
+            %(translate)s
+            try:
+                p = _proxy
+            except NameError as ne:
+                _name_error('%(name)s', ne)
+            return _proxy.%(name)s(%(apply_kw)s)
+            e
+        """
+            % {
+                "name": name,
+                "translate": translate_str,
+                "args": outer_args,
+                "apply_kw": inner_args,
+                "doc": fn.__doc__,
+            }
+        )
+        lcl: MutableMapping[str, Any] = {}
+
+        exec(func_text, cast("Dict[str, Any]", globals_), lcl)
+        return cast("Callable[..., Any]", lcl[name])
+
+
+def _with_legacy_names(translations: Any) -> Any:
+    def decorate(fn: _C) -> _C:
+        fn._legacy_translations = translations  # type: ignore[attr-defined]
+        return fn
+
+    return decorate
+
+
+def rev_id() -> str:
+    return uuid.uuid4().hex[-12:]
+
+
+@overload
+def to_tuple(x: Any, default: Tuple[Any, ...]) -> Tuple[Any, ...]:
+    ...
+
+
+@overload
+def to_tuple(x: None, default: Optional[_T] = ...) -> _T:
+    ...
+
+
+@overload
+def to_tuple(
+    x: Any, default: Optional[Tuple[Any, ...]] = None
+) -> Tuple[Any, ...]:
+    ...
+
+
+def to_tuple(
+    x: Any, default: Optional[Tuple[Any, ...]] = None
+) -> Optional[Tuple[Any, ...]]:
+    if x is None:
+        return default
+    elif isinstance(x, str):
+        return (x,)
+    elif isinstance(x, Iterable):
+        return tuple(x)
+    else:
+        return (x,)
+
+
+def dedupe_tuple(tup: Tuple[str, ...]) -> Tuple[str, ...]:
+    return tuple(unique_list(tup))
+
+
+class Dispatcher:
+    def __init__(self, uselist: bool = False) -> None:
+        self._registry: Dict[Tuple[Any, ...], Any] = {}
+        self.uselist = uselist
+
+    def dispatch_for(
+        self, target: Any, qualifier: str = "default"
+    ) -> Callable[[_C], _C]:
+        def decorate(fn: _C) -> _C:
+            if self.uselist:
+                self._registry.setdefault((target, qualifier), []).append(fn)
+            else:
+                assert (target, qualifier) not in self._registry
+                self._registry[(target, qualifier)] = fn
+            return fn
+
+        return decorate
+
+    def dispatch(self, obj: Any, qualifier: str = "default") -> Any:
+        if isinstance(obj, str):
+            targets: Sequence[Any] = [obj]
+        elif isinstance(obj, type):
+            targets = obj.__mro__
+        else:
+            targets = type(obj).__mro__
+
+        for spcls in targets:
+            if qualifier != "default" and (spcls, qualifier) in self._registry:
+                return self._fn_or_list(self._registry[(spcls, qualifier)])
+            elif (spcls, "default") in self._registry:
+                return self._fn_or_list(self._registry[(spcls, "default")])
+        else:
+            raise ValueError("no dispatch function for object: %s" % obj)
+
+    def _fn_or_list(
+        self, fn_or_list: Union[List[Callable[..., Any]], Callable[..., Any]]
+    ) -> Callable[..., Any]:
+        if self.uselist:
+
+            def go(*arg: Any, **kw: Any) -> None:
+                if TYPE_CHECKING:
+                    assert isinstance(fn_or_list, Sequence)
+                for fn in fn_or_list:
+                    fn(*arg, **kw)
+
+            return go
+        else:
+            return fn_or_list  # type: ignore
+
+    def branch(self) -> Dispatcher:
+        """Return a copy of this dispatcher that is independently
+        writable."""
+
+        d = Dispatcher()
+        if self.uselist:
+            d._registry.update(
+                (k, [fn for fn in self._registry[k]]) for k in self._registry
+            )
+        else:
+            d._registry.update(self._registry)
+        return d
+
+
+def not_none(value: Optional[_T]) -> _T:
+    assert value is not None
+    return value

.venv2/Lib/site-packages/alembic/util/messaging.py

@@ -0,0 +1,115 @@
+from __future__ import annotations
+
+from collections.abc import Iterable
+from contextlib import contextmanager
+import logging
+import sys
+import textwrap
+from typing import Iterator
+from typing import Optional
+from typing import TextIO
+from typing import Union
+import warnings
+
+from sqlalchemy.engine import url
+
+from . import sqla_compat
+
+log = logging.getLogger(__name__)
+
+# disable "no handler found" errors
+logging.getLogger("alembic").addHandler(logging.NullHandler())
+
+
+try:
+    import fcntl
+    import termios
+    import struct
+
+    ioctl = fcntl.ioctl(0, termios.TIOCGWINSZ, struct.pack("HHHH", 0, 0, 0, 0))
+    _h, TERMWIDTH, _hp, _wp = struct.unpack("HHHH", ioctl)
+    if TERMWIDTH <= 0:  # can occur if running in emacs pseudo-tty
+        TERMWIDTH = None
+except (ImportError, OSError):
+    TERMWIDTH = None
+
+
+def write_outstream(
+    stream: TextIO, *text: Union[str, bytes], quiet: bool = False
+) -> None:
+    if quiet:
+        return
+    encoding = getattr(stream, "encoding", "ascii") or "ascii"
+    for t in text:
+        if not isinstance(t, bytes):
+            t = t.encode(encoding, "replace")
+        t = t.decode(encoding)
+        try:
+            stream.write(t)
+        except OSError:
+            # suppress "broken pipe" errors.
+            # no known way to handle this on Python 3 however
+            # as the exception is "ignored" (noisily) in TextIOWrapper.
+            break
+
+
+@contextmanager
+def status(
+    status_msg: str, newline: bool = False, quiet: bool = False
+) -> Iterator[None]:
+    msg(status_msg + " ...", newline, flush=True, quiet=quiet)
+    try:
+        yield
+    except:
+        if not quiet:
+            write_outstream(sys.stdout, "  FAILED\n")
+        raise
+    else:
+        if not quiet:
+            write_outstream(sys.stdout, "  done\n")
+
+
+def err(message: str, quiet: bool = False) -> None:
+    log.error(message)
+    msg(f"FAILED: {message}", quiet=quiet)
+    sys.exit(-1)
+
+
+def obfuscate_url_pw(input_url: str) -> str:
+    u = url.make_url(input_url)
+    return sqla_compat.url_render_as_string(u, hide_password=True)  # type: ignore  # noqa: E501
+
+
+def warn(msg: str, stacklevel: int = 2) -> None:
+    warnings.warn(msg, UserWarning, stacklevel=stacklevel)
+
+
+def msg(
+    msg: str, newline: bool = True, flush: bool = False, quiet: bool = False
+) -> None:
+    if quiet:
+        return
+    if TERMWIDTH is None:
+        write_outstream(sys.stdout, msg)
+        if newline:
+            write_outstream(sys.stdout, "\n")
+    else:
+        # left indent output lines
+        lines = textwrap.wrap(msg, TERMWIDTH)
+        if len(lines) > 1:
+            for line in lines[0:-1]:
+                write_outstream(sys.stdout, "  ", line, "\n")
+        write_outstream(sys.stdout, "  ", lines[-1], ("\n" if newline else ""))
+    if flush:
+        sys.stdout.flush()
+
+
+def format_as_comma(value: Optional[Union[str, Iterable[str]]]) -> str:
+    if value is None:
+        return ""
+    elif isinstance(value, str):
+        return value
+    elif isinstance(value, Iterable):
+        return ", ".join(value)
+    else:
+        raise ValueError("Don't know how to comma-format %r" % value)

.venv2/Lib/site-packages/alembic/util/pyfiles.py

@@ -0,0 +1,114 @@
+from __future__ import annotations
+
+import atexit
+from contextlib import ExitStack
+import importlib
+import importlib.machinery
+import importlib.util
+import os
+import re
+import tempfile
+from types import ModuleType
+from typing import Any
+from typing import Optional
+
+from mako import exceptions
+from mako.template import Template
+
+from . import compat
+from .exc import CommandError
+
+
+def template_to_file(
+    template_file: str, dest: str, output_encoding: str, **kw: Any
+) -> None:
+    template = Template(filename=template_file)
+    try:
+        output = template.render_unicode(**kw).encode(output_encoding)
+    except:
+        with tempfile.NamedTemporaryFile(suffix=".txt", delete=False) as ntf:
+            ntf.write(
+                exceptions.text_error_template()
+                .render_unicode()
+                .encode(output_encoding)
+            )
+            fname = ntf.name
+        raise CommandError(
+            "Template rendering failed; see %s for a "
+            "template-oriented traceback." % fname
+        )
+    else:
+        with open(dest, "wb") as f:
+            f.write(output)
+
+
+def coerce_resource_to_filename(fname: str) -> str:
+    """Interpret a filename as either a filesystem location or as a package
+    resource.
+
+    Names that are non absolute paths and contain a colon
+    are interpreted as resources and coerced to a file location.
+
+    """
+    if not os.path.isabs(fname) and ":" in fname:
+        tokens = fname.split(":")
+
+        # from https://importlib-resources.readthedocs.io/en/latest/migration.html#pkg-resources-resource-filename  # noqa E501
+
+        file_manager = ExitStack()
+        atexit.register(file_manager.close)
+
+        ref = compat.importlib_resources.files(tokens[0])
+        for tok in tokens[1:]:
+            ref = ref / tok
+        fname = file_manager.enter_context(  # type: ignore[assignment]
+            compat.importlib_resources.as_file(ref)
+        )
+    return fname
+
+
+def pyc_file_from_path(path: str) -> Optional[str]:
+    """Given a python source path, locate the .pyc."""
+
+    candidate = importlib.util.cache_from_source(path)
+    if os.path.exists(candidate):
+        return candidate
+
+    # even for pep3147, fall back to the old way of finding .pyc files,
+    # to support sourceless operation
+    filepath, ext = os.path.splitext(path)
+    for ext in importlib.machinery.BYTECODE_SUFFIXES:
+        if os.path.exists(filepath + ext):
+            return filepath + ext
+    else:
+        return None
+
+
+def load_python_file(dir_: str, filename: str) -> ModuleType:
+    """Load a file from the given path as a Python module."""
+
+    module_id = re.sub(r"\W", "_", filename)
+    path = os.path.join(dir_, filename)
+    _, ext = os.path.splitext(filename)
+    if ext == ".py":
+        if os.path.exists(path):
+            module = load_module_py(module_id, path)
+        else:
+            pyc_path = pyc_file_from_path(path)
+            if pyc_path is None:
+                raise ImportError("Can't find Python file %s" % path)
+            else:
+                module = load_module_py(module_id, pyc_path)
+    elif ext in (".pyc", ".pyo"):
+        module = load_module_py(module_id, path)
+    else:
+        assert False
+    return module
+
+
+def load_module_py(module_id: str, path: str) -> ModuleType:
+    spec = importlib.util.spec_from_file_location(module_id, path)
+    assert spec
+    module = importlib.util.module_from_spec(spec)
+    spec.loader.exec_module(module)  # type: ignore
+    return module

.venv2/Lib/site-packages/alembic/util/sqla_compat.py

@@ -0,0 +1,665 @@
+# mypy: allow-untyped-defs, allow-incomplete-defs, allow-untyped-calls
+# mypy: no-warn-return-any, allow-any-generics
+
+from __future__ import annotations
+
+import contextlib
+import re
+from typing import Any
+from typing import Callable
+from typing import Dict
+from typing import Iterable
+from typing import Iterator
+from typing import Mapping
+from typing import Optional
+from typing import Protocol
+from typing import Set
+from typing import Type
+from typing import TYPE_CHECKING
+from typing import TypeVar
+from typing import Union
+
+from sqlalchemy import __version__
+from sqlalchemy import inspect
+from sqlalchemy import schema
+from sqlalchemy import sql
+from sqlalchemy import types as sqltypes
+from sqlalchemy.engine import url
+from sqlalchemy.schema import CheckConstraint
+from sqlalchemy.schema import Column
+from sqlalchemy.schema import ForeignKeyConstraint
+from sqlalchemy.sql import visitors
+from sqlalchemy.sql.base import DialectKWArgs
+from sqlalchemy.sql.elements import BindParameter
+from sqlalchemy.sql.elements import ColumnClause
+from sqlalchemy.sql.elements import quoted_name
+from sqlalchemy.sql.elements import TextClause
+from sqlalchemy.sql.elements import UnaryExpression
+from sqlalchemy.sql.visitors import traverse
+from typing_extensions import TypeGuard
+
+if TYPE_CHECKING:
+    from sqlalchemy import ClauseElement
+    from sqlalchemy import Index
+    from sqlalchemy import Table
+    from sqlalchemy.engine import Connection
+    from sqlalchemy.engine import Dialect
+    from sqlalchemy.engine import Transaction
+    from sqlalchemy.engine.reflection import Inspector
+    from sqlalchemy.sql.base import ColumnCollection
+    from sqlalchemy.sql.compiler import SQLCompiler
+    from sqlalchemy.sql.dml import Insert
+    from sqlalchemy.sql.elements import ColumnElement
+    from sqlalchemy.sql.schema import Constraint
+    from sqlalchemy.sql.schema import SchemaItem
+    from sqlalchemy.sql.selectable import Select
+    from sqlalchemy.sql.selectable import TableClause
+
+_CE = TypeVar("_CE", bound=Union["ColumnElement[Any]", "SchemaItem"])
+
+
+class _CompilerProtocol(Protocol):
+    def __call__(self, element: Any, compiler: Any, **kw: Any) -> str:
+        ...
+
+
+def _safe_int(value: str) -> Union[int, str]:
+    try:
+        return int(value)
+    except:
+        return value
+
+
+_vers = tuple(
+    [_safe_int(x) for x in re.findall(r"(\d+|[abc]\d)", __version__)]
+)
+sqla_13 = _vers >= (1, 3)
+sqla_14 = _vers >= (1, 4)
+# https://docs.sqlalchemy.org/en/latest/changelog/changelog_14.html#change-0c6e0cc67dfe6fac5164720e57ef307d
+sqla_14_18 = _vers >= (1, 4, 18)
+sqla_14_26 = _vers >= (1, 4, 26)
+sqla_2 = _vers >= (2,)
+sqlalchemy_version = __version__
+
+try:
+    from sqlalchemy.sql.naming import _NONE_NAME as _NONE_NAME  # type: ignore[attr-defined]  # noqa: E501
+except ImportError:
+    from sqlalchemy.sql.elements import _NONE_NAME as _NONE_NAME  # type: ignore  # noqa: E501
+
+
+class _Unsupported:
+    "Placeholder for unsupported SQLAlchemy classes"
+
+
+if TYPE_CHECKING:
+
+    def compiles(
+        element: Type[ClauseElement], *dialects: str
+    ) -> Callable[[_CompilerProtocol], _CompilerProtocol]:
+        ...
+
+else:
+    from sqlalchemy.ext.compiler import compiles
+
+try:
+    from sqlalchemy import Computed as Computed
+except ImportError:
+    if not TYPE_CHECKING:
+
+        class Computed(_Unsupported):
+            pass
+
+    has_computed = False
+    has_computed_reflection = False
+else:
+    has_computed = True
+    has_computed_reflection = _vers >= (1, 3, 16)
+
+try:
+    from sqlalchemy import Identity as Identity
+except ImportError:
+    if not TYPE_CHECKING:
+
+        class Identity(_Unsupported):
+            pass
+
+    has_identity = False
+else:
+    identity_has_dialect_kwargs = issubclass(Identity, DialectKWArgs)
+
+    def _get_identity_options_dict(
+        identity: Union[Identity, schema.Sequence, None],
+        dialect_kwargs: bool = False,
+    ) -> Dict[str, Any]:
+        if identity is None:
+            return {}
+        elif identity_has_dialect_kwargs:
+            as_dict = identity._as_dict()  # type: ignore
+            if dialect_kwargs:
+                assert isinstance(identity, DialectKWArgs)
+                as_dict.update(identity.dialect_kwargs)
+        else:
+            as_dict = {}
+            if isinstance(identity, Identity):
+                # always=None means something different than always=False
+                as_dict["always"] = identity.always
+                if identity.on_null is not None:
+                    as_dict["on_null"] = identity.on_null
+            # attributes common to Identity and Sequence
+            attrs = (
+                "start",
+                "increment",
+                "minvalue",
+                "maxvalue",
+                "nominvalue",
+                "nomaxvalue",
+                "cycle",
+                "cache",
+                "order",
+            )
+            as_dict.update(
+                {
+                    key: getattr(identity, key, None)
+                    for key in attrs
+                    if getattr(identity, key, None) is not None
+                }
+            )
+        return as_dict
+
+    has_identity = True
+
+if sqla_2:
+    from sqlalchemy.sql.base import _NoneName
+else:
+    from sqlalchemy.util import symbol as _NoneName  # type: ignore[assignment]
+
+
+_ConstraintName = Union[None, str, _NoneName]
+
+_ConstraintNameDefined = Union[str, _NoneName]
+
+
+def constraint_name_defined(
+    name: _ConstraintName,
+) -> TypeGuard[_ConstraintNameDefined]:
+    return name is _NONE_NAME or isinstance(name, (str, _NoneName))
+
+
+def constraint_name_string(
+    name: _ConstraintName,
+) -> TypeGuard[str]:
+    return isinstance(name, str)
+
+
+def constraint_name_or_none(
+    name: _ConstraintName,
+) -> Optional[str]:
+    return name if constraint_name_string(name) else None
+
+
+AUTOINCREMENT_DEFAULT = "auto"
+
+
+@contextlib.contextmanager
+def _ensure_scope_for_ddl(
+    connection: Optional[Connection],
+) -> Iterator[None]:
+    try:
+        in_transaction = connection.in_transaction  # type: ignore[union-attr]
+    except AttributeError:
+        # catch for MockConnection, None
+        in_transaction = None
+        pass
+
+    # yield outside the catch
+    if in_transaction is None:
+        yield
+    else:
+        if not in_transaction():
+            assert connection is not None
+            with connection.begin():
+                yield
+        else:
+            yield
+
+
+def url_render_as_string(url, hide_password=True):
+    if sqla_14:
+        return url.render_as_string(hide_password=hide_password)
+    else:
+        return url.__to_string__(hide_password=hide_password)
+
+
+def _safe_begin_connection_transaction(
+    connection: Connection,
+) -> Transaction:
+    transaction = _get_connection_transaction(connection)
+    if transaction:
+        return transaction
+    else:
+        return connection.begin()
+
+
+def _safe_commit_connection_transaction(
+    connection: Connection,
+) -> None:
+    transaction = _get_connection_transaction(connection)
+    if transaction:
+        transaction.commit()
+
+
+def _safe_rollback_connection_transaction(
+    connection: Connection,
+) -> None:
+    transaction = _get_connection_transaction(connection)
+    if transaction:
+        transaction.rollback()
+
+
+def _get_connection_in_transaction(connection: Optional[Connection]) -> bool:
+    try:
+        in_transaction = connection.in_transaction  # type: ignore
+    except AttributeError:
+        # catch for MockConnection
+        return False
+    else:
+        return in_transaction()
+
+
+def _idx_table_bound_expressions(idx: Index) -> Iterable[ColumnElement[Any]]:
+    return idx.expressions  # type: ignore
+
+
+def _copy(schema_item: _CE, **kw) -> _CE:
+    if hasattr(schema_item, "_copy"):
+        return schema_item._copy(**kw)
+    else:
+        return schema_item.copy(**kw)  # type: ignore[union-attr]
+
+
+def _get_connection_transaction(
+    connection: Connection,
+) -> Optional[Transaction]:
+    if sqla_14:
+        return connection.get_transaction()
+    else:
+        r = connection._root  # type: ignore[attr-defined]
+        return r._Connection__transaction
+
+
+def _create_url(*arg, **kw) -> url.URL:
+    if hasattr(url.URL, "create"):
+        return url.URL.create(*arg, **kw)
+    else:
+        return url.URL(*arg, **kw)
+
+
+def _connectable_has_table(
+    connectable: Connection, tablename: str, schemaname: Union[str, None]
+) -> bool:
+    if sqla_14:
+        return inspect(connectable).has_table(tablename, schemaname)
+    else:
+        return connectable.dialect.has_table(
+            connectable, tablename, schemaname
+        )
+
+
+def _exec_on_inspector(inspector, statement, **params):
+    if sqla_14:
+        with inspector._operation_context() as conn:
+            return conn.execute(statement, params)
+    else:
+        return inspector.bind.execute(statement, params)
+
+
+def _nullability_might_be_unset(metadata_column):
+    if not sqla_14:
+        return metadata_column.nullable
+    else:
+        from sqlalchemy.sql import schema
+
+        return (
+            metadata_column._user_defined_nullable is schema.NULL_UNSPECIFIED
+        )
+
+
+def _server_default_is_computed(*server_default) -> bool:
+    if not has_computed:
+        return False
+    else:
+        return any(isinstance(sd, Computed) for sd in server_default)
+
+
+def _server_default_is_identity(*server_default) -> bool:
+    if not sqla_14:
+        return False
+    else:
+        return any(isinstance(sd, Identity) for sd in server_default)
+
+
+def _table_for_constraint(constraint: Constraint) -> Table:
+    if isinstance(constraint, ForeignKeyConstraint):
+        table = constraint.parent
+        assert table is not None
+        return table  # type: ignore[return-value]
+    else:
+        return constraint.table
+
+
+def _columns_for_constraint(constraint):
+    if isinstance(constraint, ForeignKeyConstraint):
+        return [fk.parent for fk in constraint.elements]
+    elif isinstance(constraint, CheckConstraint):
+        return _find_columns(constraint.sqltext)
+    else:
+        return list(constraint.columns)
+
+
+def _reflect_table(inspector: Inspector, table: Table) -> None:
+    if sqla_14:
+        return inspector.reflect_table(table, None)
+    else:
+        return inspector.reflecttable(  # type: ignore[attr-defined]
+            table, None
+        )
+
+
+def _resolve_for_variant(type_, dialect):
+    if _type_has_variants(type_):
+        base_type, mapping = _get_variant_mapping(type_)
+        return mapping.get(dialect.name, base_type)
+    else:
+        return type_
+
+
+if hasattr(sqltypes.TypeEngine, "_variant_mapping"):
+
+    def _type_has_variants(type_):
+        return bool(type_._variant_mapping)
+
+    def _get_variant_mapping(type_):
+        return type_, type_._variant_mapping
+
+else:
+
+    def _type_has_variants(type_):
+        return type(type_) is sqltypes.Variant
+
+    def _get_variant_mapping(type_):
+        return type_.impl, type_.mapping
+
+
+def _fk_spec(constraint: ForeignKeyConstraint) -> Any:
+    if TYPE_CHECKING:
+        assert constraint.columns is not None
+        assert constraint.elements is not None
+        assert isinstance(constraint.parent, Table)
+
+    source_columns = [
+        constraint.columns[key].name for key in constraint.column_keys
+    ]
+
+    source_table = constraint.parent.name
+    source_schema = constraint.parent.schema
+    target_schema = constraint.elements[0].column.table.schema
+    target_table = constraint.elements[0].column.table.name
+    target_columns = [element.column.name for element in constraint.elements]
+    ondelete = constraint.ondelete
+    onupdate = constraint.onupdate
+    deferrable = constraint.deferrable
+    initially = constraint.initially
+    return (
+        source_schema,
+        source_table,
+        source_columns,
+        target_schema,
+        target_table,
+        target_columns,
+        onupdate,
+        ondelete,
+        deferrable,
+        initially,
+    )
+
+
+def _fk_is_self_referential(constraint: ForeignKeyConstraint) -> bool:
+    spec = constraint.elements[0]._get_colspec()
+    tokens = spec.split(".")
+    tokens.pop(-1)  # colname
+    tablekey = ".".join(tokens)
+    assert constraint.parent is not None
+    return tablekey == constraint.parent.key
+
+
+def _is_type_bound(constraint: Constraint) -> bool:
+    # this deals with SQLAlchemy #3260, don't copy CHECK constraints
+    # that will be generated by the type.
+    # new feature added for #3260
+    return constraint._type_bound
+
+
+def _find_columns(clause):
+    """locate Column objects within the given expression."""
+
+    cols: Set[ColumnElement[Any]] = set()
+    traverse(clause, {}, {"column": cols.add})
+    return cols
+
+
+def _remove_column_from_collection(
+    collection: ColumnCollection, column: Union[Column[Any], ColumnClause[Any]]
+) -> None:
+    """remove a column from a ColumnCollection."""
+
+    # workaround for older SQLAlchemy, remove the
+    # same object that's present
+    assert column.key is not None
+    to_remove = collection[column.key]
+
+    # SQLAlchemy 2.0 will use more ReadOnlyColumnCollection
+    # (renamed from ImmutableColumnCollection)
+    if hasattr(collection, "_immutable") or hasattr(collection, "_readonly"):
+        collection._parent.remove(to_remove)
+    else:
+        collection.remove(to_remove)
+
+
+def _textual_index_column(
+    table: Table, text_: Union[str, TextClause, ColumnElement[Any]]
+) -> Union[ColumnElement[Any], Column[Any]]:
+    """a workaround for the Index construct's severe lack of flexibility"""
+    if isinstance(text_, str):
+        c = Column(text_, sqltypes.NULLTYPE)
+        table.append_column(c)
+        return c
+    elif isinstance(text_, TextClause):
+        return _textual_index_element(table, text_)
+    elif isinstance(text_, _textual_index_element):
+        return _textual_index_column(table, text_.text)
+    elif isinstance(text_, sql.ColumnElement):
+        return _copy_expression(text_, table)
+    else:
+        raise ValueError("String or text() construct expected")
+
+
+def _copy_expression(expression: _CE, target_table: Table) -> _CE:
+    def replace(col):
+        if (
+            isinstance(col, Column)
+            and col.table is not None
+            and col.table is not target_table
+        ):
+            if col.name in target_table.c:
+                return target_table.c[col.name]
+            else:
+                c = _copy(col)
+                target_table.append_column(c)
+                return c
+        else:
+            return None
+
+    return visitors.replacement_traverse(  # type: ignore[call-overload]
+        expression, {}, replace
+    )
+
+
+class _textual_index_element(sql.ColumnElement):
+    """Wrap around a sqlalchemy text() construct in such a way that
+    we appear like a column-oriented SQL expression to an Index
+    construct.
+
+    The issue here is that currently the Postgresql dialect, the biggest
+    recipient of functional indexes, keys all the index expressions to
+    the corresponding column expressions when rendering CREATE INDEX,
+    so the Index we create here needs to have a .columns collection that
+    is the same length as the .expressions collection.  Ultimately
+    SQLAlchemy should support text() expressions in indexes.
+
+    See SQLAlchemy issue 3174.
+
+    """
+
+    __visit_name__ = "_textual_idx_element"
+
+    def __init__(self, table: Table, text: TextClause) -> None:
+        self.table = table
+        self.text = text
+        self.key = text.text
+        self.fake_column = schema.Column(self.text.text, sqltypes.NULLTYPE)
+        table.append_column(self.fake_column)
+
+    def get_children(self):
+        return [self.fake_column]
+
+
+@compiles(_textual_index_element)
+def _render_textual_index_column(
+    element: _textual_index_element, compiler: SQLCompiler, **kw
+) -> str:
+    return compiler.process(element.text, **kw)
+
+
+class _literal_bindparam(BindParameter):
+    pass
+
+
+@compiles(_literal_bindparam)
+def _render_literal_bindparam(
+    element: _literal_bindparam, compiler: SQLCompiler, **kw
+) -> str:
+    return compiler.render_literal_bindparam(element, **kw)
+
+
+def _column_kwargs(col: Column) -> Mapping:
+    if sqla_13:
+        return col.kwargs
+    else:
+        return {}
+
+
+def _get_constraint_final_name(
+    constraint: Union[Index, Constraint], dialect: Optional[Dialect]
+) -> Optional[str]:
+    if constraint.name is None:
+        return None
+    assert dialect is not None
+    if sqla_14:
+        # for SQLAlchemy 1.4 we would like to have the option to expand
+        # the use of "deferred" names for constraints as well as to have
+        # some flexibility with "None" name and similar; make use of new
+        # SQLAlchemy API to return what would be the final compiled form of
+        # the name for this dialect.
+        return dialect.identifier_preparer.format_constraint(
+            constraint, _alembic_quote=False
+        )
+    else:
+        # prior to SQLAlchemy 1.4, work around quoting logic to get at the
+        # final compiled name without quotes.
+        if hasattr(constraint.name, "quote"):
+            # might be quoted_name, might be truncated_name, keep it the
+            # same
+            quoted_name_cls: type = type(constraint.name)
+        else:
+            quoted_name_cls = quoted_name
+
+        new_name = quoted_name_cls(str(constraint.name), quote=False)
+        constraint = constraint.__class__(name=new_name)
+
+        if isinstance(constraint, schema.Index):
+            # name should not be quoted.
+            d = dialect.ddl_compiler(dialect, None)  # type: ignore[arg-type]
+            return d._prepared_index_name(constraint)
+        else:
+            # name should not be quoted.
+            return dialect.identifier_preparer.format_constraint(constraint)
+
+
+def _constraint_is_named(
+    constraint: Union[Constraint, Index], dialect: Optional[Dialect]
+) -> bool:
+    if sqla_14:
+        if constraint.name is None:
+            return False
+        assert dialect is not None
+        name = dialect.identifier_preparer.format_constraint(
+            constraint, _alembic_quote=False
+        )
+        return name is not None
+    else:
+        return constraint.name is not None
+
+
+def _is_mariadb(mysql_dialect: Dialect) -> bool:
+    if sqla_14:
+        return mysql_dialect.is_mariadb  # type: ignore[attr-defined]
+    else:
+        return bool(
+            mysql_dialect.server_version_info
+            and mysql_dialect._is_mariadb  # type: ignore[attr-defined]
+        )
+
+
+def _mariadb_normalized_version_info(mysql_dialect):
+    return mysql_dialect._mariadb_normalized_version_info
+
+
+def _insert_inline(table: Union[TableClause, Table]) -> Insert:
+    if sqla_14:
+        return table.insert().inline()
+    else:
+        return table.insert(inline=True)  # type: ignore[call-arg]
+
+
+if sqla_14:
+    from sqlalchemy import create_mock_engine
+
+    # weird mypy workaround
+    from sqlalchemy import select as _sa_select
+
+    _select = _sa_select
+else:
+    from sqlalchemy import create_engine
+
+    def create_mock_engine(url, executor, **kw):  # type: ignore[misc]
+        return create_engine(
+            "postgresql://", strategy="mock", executor=executor
+        )
+
+    def _select(*columns, **kw) -> Select:
+        return sql.select(list(columns), **kw)  # type: ignore[call-overload]
+
+
+def is_expression_index(index: Index) -> bool:
+    for expr in index.expressions:
+        if is_expression(expr):
+            return True
+    return False
+
+
+def is_expression(expr: Any) -> bool:
+    while isinstance(expr, UnaryExpression):
+        expr = expr.element
+    if not isinstance(expr, ColumnClause) or expr.is_literal:
+        return True
+    return False