Binder doesn't work well with Type[...]

This code:

from typing import Union, Type

class C: ...

x: Union[C, Type[C]]

if isinstance(x, type) and issubclass(x, C):
    reveal_type(x)

Shows that the type of x is builtins.type. Ideally it should be Type[C].

Is this the same as:

class A:
    x = 4


i: type = A
assert issubclass(i, A)
print(i.x)

which fails with:

7: error: "type" has no attribute "x"

?

mypy 0.590

It looks like issubclass doesn't imply anything AFAICT, unlike isinstance.

There's this workaround:

i: type = A
j: Type[A] = i
print(j.x)

but since this isn't in assertion format it seems more like a static check omission.

Yes, this is the same bug.

Just got bit by this one.

(Removing unions tag since there are repros without unions, and increasing priority to high since this appeared several times again.)

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