TST: fix running a regression test with pytest 7 - #16726

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Thanks! I just added Extra CI label. I will approve when results come in, uh, at the end of my work day (lol).

@pllim sorry I wasn't clear: this does not fix #16724, and extra CI will still fail, just with a less confusing log !

Well, should we also attach the fix here?

Also maybe need a rebase to pick up your mpl-dev fix?

Thanks!

I wonder if we should have a regular CI job pinned to pytest 7. 🤔

Well, should we also attach the fix here?

That would require knowledge of a fix, which at the moment I don't have 👼🏻

Also maybe need a rebase to pick up your mpl-dev fix?

done

I wonder if we should have a regular CI job pinned to pytest 7. 🤔

I think errors are rare enough that we don't need one. In 6 month we should be able to set pytest 8.0 as our minimum requirement anyway :)

wait... if CI is to be believed, this is actually apparently sufficient to fix #16724 by itself. I won't pretend that I get why, but all the better.

Hmm. Okay... So maybe that warning causes pytest to throw exception at a weird place, and the ValueError: fast C time string parser failed: non-digit found where digit (0-9) required is a red herring? 🤔

Link check failure is unrelated. I will wait till aarch64 completes before approving. Thanks!

If it is indeed caused by recent change by @ayshih , that means somehow the change makes the warning pops up even with the limitation of older pytest, which would theoretically mean that the backport would not be needed, but it would be obvious when the backport PR fails on the "exotic" jobs.

Thanks!