Type narrowing for LiteralString does not work #3466
Description
Describe the bug
Given the following code:
from collections.abc import Sequence
from typing import Any, TypeGuard
from typing_extensions import LiteralString, reveal_type
def _is_literal_string(obj: Any) -> TypeGuard[LiteralString]:
return isinstance(obj, str)
def foo(s: str | Sequence[str]) -> None:
if isinstance(s, str):
reveal_type(s)
else:
reveal_type(s)
def bar(s: LiteralString | Sequence[LiteralString]) -> None:
if _is_literal_string(s):
reveal_type(s)
else:
reveal_type(s)The output on the command line is as follows:
test.py:8:21 - information: Type of "s" is "str"
test.py:10:21 - information: Type of "s" is "Sequence[str]"
test.py:19:21 - information: Type of "s" is "LiteralString"
test.py:21:21 - information: Type of "s" is "LiteralString | Sequence[LiteralString]"
Expected behavior
The type reported on line 21 should be Sequence[LiteralString].
VS Code extension or command-line
Are you running pyright as a VS Code extension or a command-line tool?
Command line
Which version?
1.1.247