First overload picked overeagerly when overloading on self type

[JelleZijlstra]

Consider this example:

from typing import Generic, TypeVar, Any, overload

AnyStr = TypeVar("AnyStr", str, bytes)

class Popen(Generic[AnyStr]):
 @overload
 def communicate(self: Popen[str], buf: str = ...) -> float: ...
 @overload
 def communicate(self: Popen[bytes], buf: memoryview | bytes = ...) -> range: ...
 def communicate(self, buf: object = None) -> Any: raise NotImplementedError

p = Popen()
reveal_type(p.communicate())

This currently reveals float. I think it should either be the union float | range or Any. This came up in python/typeshed#9100.

[mr-c]

I can confirm that this is still an issue with mypy 1.15, especially for mypyc users when subprocess.Popen (or similar) is called with stdout=subprocess.DEVNULL