regression due to #11055 about sqlalchemy

[zzzeek]

@francipvb any chance you can take a look at this and suggest corrections?

cc @CaselIT @agronholm

[CaselIT]

mypy is saying:

This is likely because "reflect of MetaData" has named arguments: "bind". Consider marking them positional-only

If I apply this change

diff --git a/lib/sqlalchemy/sql/schema.py b/lib/sqlalchemy/sql/schema.py
index 8436aac43..780576e32 100644
--- a/lib/sqlalchemy/sql/schema.py
+++ b/lib/sqlalchemy/sql/schema.py
@@ -5691,6 +5691,7 @@ class MetaData(HasSchemaAttr):
     def reflect(
         self,
         bind: Union[Engine, Connection],
+        /,
         schema: Optional[str] = None,
         views: bool = False,
         only: Union[

then everything passes.

But we can't do that on 2.0 since 3.7 does not support them (IIRC)

[CaselIT]

This is also liked by mypy:

diff --git a/lib/sqlalchemy/sql/schema.py b/lib/sqlalchemy/sql/schema.py
index 8436aac43..04774d190 100644
--- a/lib/sqlalchemy/sql/schema.py
+++ b/lib/sqlalchemy/sql/schema.py
@@ -5690,7 +5690,7 @@ class MetaData(HasSchemaAttr):
     @util.preload_module("sqlalchemy.engine.reflection")
     def reflect(
         self,
-        bind: Union[Engine, Connection],
+        __bind: Union[Engine, Connection],
         schema: Optional[str] = None,
         views: bool = False,
         only: Union[
@@ -5786,7 +5786,7 @@ class MetaData(HasSchemaAttr):

         """

-        with inspection.inspect(bind)._inspection_context() as insp:
+        with inspection.inspect(__bind)._inspection_context() as insp:
             reflect_opts: Any = {
                 "autoload_with": insp,
                 "extend_existing": extend_existing,
@@ -5844,7 +5844,7 @@ class MetaData(HasSchemaAttr):
                     missing_str = ", ".join(missing)
                     raise exc.InvalidRequestError(
                         f"Could not reflect: requested table(s) not available "
-                        f"in {bind.engine!r}{s}: ({missing_str})"
+                        f"in {__bind.engine!r}{s}: ({missing_str})"
                     )
                 load = [
                     name

Overall this seems more like a bug of mypy.
pylance and pyright report no errors

[zzzeek]

we can't change that name because people may send it by name.

can we change the paramspec and/or add alternate paramspecs that work with metadata.reflect as is ?

[CaselIT]

I'm not sure. Maybe we can use some overloads?

Would it make sense to report this to mypy.

[francipvb]

Hello,

I'm looking into this. It seems that mypy is more strict with this usecase.

[zzzeek]

can we get the PR for this?

[sqla-tester]

Francisco Del Roio has proposed a fix for this issue in the main branch:

Fix typing issue in MetaData.reflect() in AsyncIO context https://gerrit.sqlalchemy.org/c/sqlalchemy/sqlalchemy/+/5242

[sqla-tester]

Francisco Del Roio has proposed a fix for this issue in the rel_2_0 branch:

Fix typing issue in MetaData.reflect() in AsyncIO context https://gerrit.sqlalchemy.org/c/sqlalchemy/sqlalchemy/+/5263

[sqla-tester]

Francisco Del Roio has proposed a fix for this issue in the main branch:

Fix typing issue in MetaData.reflect() with asyncio. https://gerrit.sqlalchemy.org/c/sqlalchemy/sqlalchemy/+/5242