Closed
Description
Bug Report
When calling an inherited decorated classmethod that returns Self, mypy does not resolve the type and thinks the type of the return value is Self.
To Reproduce
https://mypy-play.net/?mypy=latest&python=3.13&flags=strict&gist=664aeee2f4339ce869129dfba8017289
from __future__ import annotations
from collections.abc import Callable
from functools import wraps
from typing import Any, Self, TypeVar
type JSON = dict[str, Any]
T = TypeVar("T")
def debug(make: Callable[[type[T], JSON], T]) -> Callable[[type[T], JSON], T]:
@wraps(make)
def wrapper(cls: type[T], data: JSON) -> T:
return make(cls, data)
return wrapper
class Foo:
data: JSON
def __init__(self, data: JSON) -> None:
self.data = data
@classmethod
@debug
def make(cls, data: JSON) -> Self:
return cls(data)
class Bar(Foo):
pass
def test() -> Bar:
return Bar.make({})Expected Behavior
The code should type check.
Actual Behavior
main.py:36: error: Incompatible return value type (got "Self", expected "Bar") [return-value]
Found 1 error in 1 file (checked 1 source file)
Your Environment
- Mypy version used: 1.15.0
- Mypy command-line flags:
--strict - Python version used: 3.13