Bug Report
mypy does not infer correctly with a __class__ override.
To Reproduce
https://mypy-play.net/?gist=9e3ffebda54d02c5e68f45fe7cd33eb0
from typing import Any, Protocol, overload, reveal_type
from collections.abc import Iterator, Sequence
from typing_extensions import TypeVar
_T_co = TypeVar("_T_co", covariant=True)
class ReducedCovariantList(Protocol[_T_co]):
@property
def __class__(self) -> type[list[Any]]: ...
def __iter__(self) -> Iterator[_T_co]: ...
@overload
def foo(x: ReducedCovariantList[str]) -> str: ...
@overload
def foo(x: Sequence[int]) -> int: ...
# ty gives Unknown; mypy gives str; pyright and pyrefly give int
reveal_type(foo([1]))
# if we remove the __class__ override, both ty and mypy give int
Expected Behaviour
reveal_type gives int
Actual Behavior
reveal_type gives str
Your Environment
- Mypy version used: 2.3.0
- Mypy command-line flags: -
- Mypy configuration options from
mypy.ini (and other config files): -
- Python version used: 3.12
Bug Report
mypydoes not infer correctly with a__class__override.To Reproduce
https://mypy-play.net/?gist=9e3ffebda54d02c5e68f45fe7cd33eb0
Expected Behaviour
reveal_typegivesintActual Behavior
reveal_typegivesstrYour Environment
mypy.ini(and other config files): -