Update mypy to 1.20.1

[LecrisUT]

Summary

Noticed that the tests were failing locally but not in CI in my recent PR, and turned out it was mypy not working with the latest version. I don't know what the policy is for supporting older mypy so here is a more minimal patch to make it work with the version in the uv.lock. Fwiw, Fedora's tests do not run the mypy tests.

Pull Request Check List

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    The next version is the second number in the current release + 1.
    The first number represents the current year.
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[hynek]

oh my god it they changed the syntax all again – thanks for the fix!

[hynek]

OK, it might be that we have to revert this and talk to the Mypy people. With both 1.20.0 and 1.20.1, the pytest -k test_mypy passes for me only once which makes no sense:

Does it work for you reliably?

cc @Tinche

[LecrisUT]

Does it work for you reliably?

That is really weird, yes it works reliably for me, although I did not run it with uv run, just directly pytest -k mypy 🤔.

Edit: Ok I've ran them with uv as well and it worked on my side. What black magic is going on?

[hynek]

what platform are you on?

[LecrisUT]

what platform are you on?

Linux (Fedora). I reckon it's not specific to me and could replicate in a container

[hynek]

I mean I am the one who has a weirdly behaving Mypy. :) And I'm on macOS.

[LecrisUT]

Well, at least in the worst case those test cases can be converted to a regex 🙃

[hynek]

looks like I "fixed" it by disabling caching on that test #1546