Metaclass Usage Example Code Incorrect #18668
Description
Documentation
The Metaclasses usage example code seems to be incorrect: https://mypy.readthedocs.io/en/stable/metaclasses.html#metaclass-usage-example
If check the given code snippet:
from typing import ClassVar, Self
class M(type):
count: ClassVar[int] = 0
def make(cls) -> Self:
M.count += 1
return cls()I get:
$ mypy --strict test.py
test.py:7: error: Self type cannot be used in a metaclass [misc]
test.py:9: error: Returning Any from function declared to return "Self" [no-any-return]
Found 2 errors in 1 file (checked 1 source file)I think the second error is a consequence of the first. The relevant PEP 673 mentions Self is not allowed in a metaclass:
https://peps.python.org/pep-0673/#valid-locations-for-self
$ python --version
Python 3.11.10
$ mypy --version
mypy 1.15.0 (compiled: yes)