F821: false negatives when a file has from __future__ import annotations #10340
Description
Ruff currently emits no F821 errors on this .py file, but the lines marked with XXX all fail at runtime due to undefined names:
from __future__ import annotations
from typing import TypeAlias, Optional, Union
MaybeCStr: TypeAlias = Optional[CStr] # XXX
MaybeCStr2: TypeAlias = Optional["CStr"] # always okay
CStr: TypeAlias = Union[C, str] # XXX
CStr2: TypeAlias = Union["C", str] # always okay
class C: ...
class Leaf: ...
class Tree(list[Tree | Leaf]): ... # XXX
class Tree2(list["Tree | Leaf"]): ... # always okayNote:
- Ruff correctly emits three errors on this file when
from __future__ import annotationsis not included - Ruff correctly emits no errors on this file if it's a
.pyistub file.