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--warn-redundant-cast doesn’t warn for simple generic types #21796
Description
Bug Report
See reproducer
To Reproduce
from typing import TypeVar, cast
T = TypeVar("T")
def identity(xs: list[T]) -> list[T]:
return xs
def f(xs: list[int]) -> list[int]:
reveal_type(identity(xs))
return cast(list[int], identity(xs)) # --warn-redundant-casts should trigger hereExpected Behavior
warns that the cast is redundant
Actual Behavior
doesn’t warn
Your Environment
- Mypy version used: 2.3.0
- Mypy command-line flags:
--warn-redundant-casts - Mypy configuration options from
mypy.ini(and other config files):warn-redundant-casts = true - Python version used: any
Activity
Yoruxyv commentedon Aug 2, 2026
Hi! I’d be happy to take a look at this if no one is already working on it. I’ll first reproduce the issue on current main, then investigate the redundant-cast check and add a focused regression test with the fix. I’ll keep the change scoped to this behavior.