Add workaround for Pytest 7.0.0 stacktrace normalization bug

[jiridanek]

Workarounds pytest-dev/pytest#9610

[jiridanek]

pytest 7.0.1 came out today, containing a fix

[jiridanek]

This is no longer necessary. I still think that the changes in the PR are nice and helpful, but now it is not fixing anything. I'll close this in a few days if there is no feedback.

[kgiusti]

The changes LGTM - one question: these changes imply that TestCases should call setUp() instead of using an init method. So going forward should we avoid using init in favor of setUp? thanks.

[kgiusti]

The changes do improve the code regardless.

[jiridanek]

The changes LGTM - one question: these changes imply that TestCases should call setUp() instead of using an init method. So going forward should we avoid using init in favor of setUp? thanks.

I think so. Defining __init__ in TestCase instances is unusual. I wouldn't do it, unless there is a compelling reason. Using setUp when possible avoids having to deal with the __init__'s optional argument, which is a distraction (and scause of the original Pytest problems here).

Going further forward, I'd consider using Pytest ways of doing things, exclusively, with the proviso that some custom work is needed to make integration/system testing convenient (pytest-dev/pytest#9141, but current python unittest suffers from the same problem, or lack of feature, to be precise.)