Non-applicable overloads should not be requested in subclasses

[vnmabus]

In the following case, Mypy complains about an invalid signature for the foo method in the implementation class, as it was missing an overload.

However, the missing overload is not applicable to that subclass and should not be requested.

from __future__ import annotations

from typing import overload, Generic, TypeVar

T = TypeVar("T")

class Interface(Generic[T]):
    @overload
    def foo(self: Interface[None]) -> int:
        ...

    @overload
    def foo(self, a: T) -> int:
        ...

    def foo(self, a: T | None = None) -> str | int:
        return 1


class Implementation(Interface[int]):
    
    def foo(self, a: int) -> int:
        return 2

Originally posted by @vnmabus in #13106 (comment)

[erictraut]

This appears to have been fixed in mypy 1.2.0.

[AlexWaygood]

Yeah, I think I remember the PR that fixed it, as well. Thanks!