Also test on PyPy 3.7

[DanielNoord]

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Type of Changes

	Type
✓	🔨 Refactoring

Description

See #5849 (comment).

[Pierre-Sassoulas]

I'm ok with fixing the issue with the line/col either in 2.13 or 2.14 :)

[cdce8p]

This shouldn't be necessary. The Set up Python version will output ${{ matrix.python-version }}. As far as I can tell, the tests didn't crash.

https://github.com/PyCQA/pylint/runs/5376859270?check_suite_focus=true

[DanielNoord]

Hmm, this doesn't work as well.

Please see the version of pytest in the pypy-3.7 run. That's the 3.6 version. You can see they are using the same cache in the Restore Python virtual environment job. The key is the same.

However, my fix also doesn't work. I guess something weird is going on with python-version and PyPy? For the cpython jobs the keys do work..

[cdce8p]

This pretty much looks like a bug in the setup-python actions. If I had to guess a result of actions/setup-python#342.

[DanielNoord]

I opened actions/setup-python#345.

I'll draft this until I get a response.

[cdce8p]

I've included the fix in #5868
Not sure when the bug will be addressed. We can always revert it, once a new version is released.

After #5868 is done, we should be able to move forward here.

[DanielNoord]

There is an issue with the current caching on PyPy. For some reason steps.python.outputs.python-version is empty on the PyPy jobs. I'm not sure why.
You can see in the first commit checks that pypy-3.7 actually uses 3.6 for pytest. They share the same cache. For 3.6 and 3.7 this isn't a problem, but it will be when we add 3.8 and it was also the causes of the issues I had in #5849.

I could do a separate PR for the fix, but I think it should be fine to squash here, or to add two commits and rebase here.

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For the future: we should remove 3.6 when we officially drop support of 3.6. After that we should look into testing PyPy on 3.8 as well and seeing what that requires from us.

[coveralls]

Pull Request Test Coverage Report for Build 1916864181

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 93.997%

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Totals
Change from base Build 1916776999:	0.0%
Covered Lines:	14937
Relevant Lines:	15891

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💛 - Coveralls

[cdce8p]

I've rebased the PR to only include the addition of pypy-3.7.
Don't know if you wanted to do anything else, so will leave it as draft for now. Feel free to merge it though if it's finished.

[DanielNoord]

Thanks @cdce8p, I'm going to merge this!