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type without arguments becomes type[nothing] instead of type[Any] #16001

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@eltoder

Description

To Reproduce

https://mypy-play.net/?mypy=latest&python=3.11&gist=07773fc6948673f0c4279ecf835537cc

from typing import Any, TypeVar, assert_type

T = TypeVar("T")

def fn(x: type[T]) -> list[T]:
    return []

def test(x: type) -> None:
    assert_type(fn(x), list[Any])

Expected Behavior

I expect this to work. According to PEP 484: https://peps.python.org/pep-0484/#the-type-of-class-objects

Plain Type without brackets is equivalent to Type[Any] and this in turn is equivalent to type (the root of Python’s metaclass hierarchy).

Actual Behavior

main.py:9: error: Expression is of type "list[<nothing>]", not "list[Any]"  [assert-type]

The type parameter for type became nothing instead of Any. However, if I explicitly use type[Any] this works as expected:

def test(x: type[Any]) -> None:
    assert_type(fn(x), list[Any])

It also works if I use typing.Type without arguments instead of type.

Your Environment

  • Mypy version used: 1.5.1
  • Python version used: 3.11

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