Typing issue with Annotated

[AlexanderPodorov]

Describe the bug
See example code snippet

from dataclasses import dataclass
from typing import Annotated


@dataclass
class Test:
    pass


TestAnnonated = Annotated[Test, ...]


def test(a: type[Test]) -> None:
    return None


# Shows warning in Pylance v2024.2.1 (Pyright 1.1.348)
# No warning in Pylance v2023.12.1 (Pyright 1.1.336)
test(TestAnnonated)

# This works:
test(Test)

VS Code extension or command-line
Pylance v2024.2.1 (Pyright 1.1.348)

[erictraut]

Pyright's behavior is correct here. The special form Annotated is not compatible with type when used in a value expression. Annotated is intended to be used to be used in a type expression (an annotation), not in a value expression. Pyright previously didn't generate an error here as it should have. Mypy correct does. I've been working to make pyright more conformant with the official typing spec.

You can also read more about this in this typing forum thread.