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How do devs feel about <https://github.com/typeddjango/pytest-mypy-plugins> :thread: ?

I'm working on some particularly picky type-annotated code, where it's really easy to "get it wrong". I'd like to add tests to ensure that certain property scopes didn't get narrowed.

E.g. if property is supposed to return `str | None`  (and not the accidental `str` ) there's no way to enforce this. Declaring a variable of type `str | None` isn't sufficient as `mypy` is happy to "promote" `str` to fit into `str | None`.

The only way I've found so far is to `assert x is None` followed by some code after it, in which `mypy` will complain about unreachable code if `x` is type `str`.

+1 for me. I always thought that that was just a convience for running MyPy against your own code via `pytest` rather than having to use `pytest` + `mypy`, so I had no interest

But if it's specifically to test our type hints are correct, cool!

(I'll add this to the backlog and, of course, try it in a different PR)

(It'll make the test lockfile include `mypy` :sweat_smile: )