Closed as not planned
Description
Bug Report
Annotating a generic function which accepts a class name as one of its arguments produces a false negative if that argument has a default.
To Reproduce
class User:
# Defines fields like name, email
class BasicUser(User):
def upgrade(self):
"""Upgrade to Pro"""
class ProUser(User):
def pay(self):
"""Pay bill"""
def new_user[U: User](user_class: type[U] = User) -> U: # Error reported here.
user = user_class()
return userExpected Behavior
No error should be reported.
Actual Behavior
Mypy reports Incompatible default for argument "user_class" (default has type "type[User]", argument has type "type[U]").
The use of the new generic syntax is irrelevant., i.e. the following
from typing import TypeVar
U = TypeVar('U', bound=User)
def new_user(user_class: type[U] = User) -> U:
...produces the same error.
Your Environment
- Mypy version used: 1.11.2
- Mypy command-line flags: --enable-incomplete-feature=NewGenericSyntax
- Mypy configuration options from
mypy.ini(and other config files): - Python version used: 3.12