revision function's type annotation is partial.

[mmohaveri]

Describe the bug

Revision function's type annotation causes "Type is partially unknown" error. The root of the issue is that process_revision_directives's argument has been typed with Callable which is a partial type (as it lacks definition of the signature of the function).

Expected behavior
I expect the type of the process_revision_directives to be fully defined so type checkers like Pyright won't give me an error.

To Reproduce
Just write any code that imports revision and run pyright on it.

[zzzeek]

hey there -

here's a script, I can't get it to reproduce a problem, does this cause a problem on your end?

from alembic.script import revision

map_ = revision.RevisionMap(
    lambda: [
        revision.Revision("a", ()),
        revision.Revision("b", ("a",)),
        revision.Revision("c", ("b",)),
    ]
)

[zzzeek]

oh. you mean "from alembic.command import revision".

[sqla-tester]

Mike Bayer has proposed a fix for this issue in the main branch:

add typing parameters https://gerrit.sqlalchemy.org/c/sqlalchemy/alembic/+/4179