Dict comprehensions fail in NamedTuple

[edward-io]

from typing import Dict, Any, NamedTuple

def out() -> str:
    return "out"

d = {"x": 0, "y": 1}

class Test(NamedTuple):
    qwer: Dict[str, Any] = {k: v for k, v in d}

Fails mypy with error:

main.py:13: error: Name 'k' is not defined
main.py:13: error: Name 'v' is not defined
Found 2 errors in 1 file (checked 1 source file)

Oddly, removing the out function makes type checking work again:

from typing import Dict, Any, NamedTuple


d = {"x": 0, "y": 1}


class Test(NamedTuple):
    qwer: Dict[str, Any] = {k: v for k, v in d}

Success: no issues found in 1 source file

Playground URL: https://mypy-play.net/?mypy=latest&python=3.8&gist=aa715bc0f6d14152487d753f3fa64885

[msullivan]

Moving out below the namedtuple also makes it work. That is deeply weird.

Some semantic analyzer weirdness I think.

[Arshaan-256]

The check is actually supposed to fail right? Can I work on this?

[edward-io]

@Arshaan-256 The check should succeed, I believe. All the code is valid Python and the types look correct.

[JelleZijlstra]

Still reproduces, and I agree with Sully that this is really weird.

Note that the code sample has a typo: it should be for k, v in d.items().