Fixed Python coverage on GitHub Actions

[radarhere]

In GitHub Actions, test.yml and test-windows.yml are not reporting Python coverage. This PR fixes that.

For test.yml, the clearest evidence that something is wrong is that macOS code is not covered.

While Travis has a line 'Generating coverage xml reports for Python', GHA has 'Python coveragepy not found'.

Looking at codecov, a way around the 'Python coveragepy not found' error is to provide a coverage.xml file.

So, in after_success.sh, we can replace coverage report with coverage xml to output the data to an XML file.

For test-windows.yml, it looks like essentially the 'After success' step was just omitted in #4084. Adding that, in combination with the first part of this PR, adds Python coverage.

[hugovk]

Whilst we're here, Codecov no longer support .codecov.yml, only codecov.yml:

• https://docs.codecov.io/docs/codecov-yaml#section-can-i-name-the-file-codecov-yml

They used to support both:

• https://web.archive.org/web/20190430062713/https://docs.codecov.io/docs/codecov-yaml#section-can-i-name-the-file-codecov-yml-

Shall we switch back in this PR or another?

[radarhere]

Ok, I've added a commit to switch the filename.

[nulano]

Should the shell be specified for Windows? The default is powershell, I'm guessing PowerShell opened the .ci/after_success.sh script in bash based on the filename, but I'm not sure I would rely on this behavior to work indefinitely.

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It looks like there is still no Python coverage from the Docker jobs on GHA, but there is C coverage (You have to unselect all, then select e.g. GHA>amazon-1-amd64; I couldn't find a direct link). Looking back, it was already missing when #4316 was merged. It looks like it is failing to find the Python source code.

[hugovk]

Windows shell: sounds wise to specify the shell rather than relying on the default. GHA has been a bit of a moving target.

---

Docker: interesting, let's deal with that separately, please can you open a new issue?

Confirmed in this Docker-only build:

• https://github.com/hugovk/Pillow/commit/f75c33940fe394d97445b8b67dcf9f43fc62adf4/checks?check_suite_id=408797442
• https://codecov.io/gh/hugovk/Pillow/commit/f75c33940fe394d97445b8b67dcf9f43fc62adf4/build
• https://codecov.io/gh/hugovk/Pillow/tree/f75c33940fe394d97445b8b67dcf9f43fc62adf4

(At the "Docker build" step, it reports coverage on Python files like /vpy3/lib/python3.8/site-packages/Pillow-7.1.0.dev0-py3.8-linux-x86_64.egg/PIL/BdfFontFile.py, perhaps it's the path causing issues. Or perhaps generating xml would help there too.)

And that's a good tip about unselecting, thanks.

[hugovk]

Codecov bot commenting means it didn't read comment: off in [.]codecov.yml. Maybe due to it being in transition in this PR. Let's hope it'll be fine when merged.

[radarhere]

Ok, I've added a commit to specify the shell for Windows.

[radarhere]

I've added a commit to fix Python coverage on Docker GHA. It can't find the Python files, so I'm moving them into place. However, it tries to look for PIL/_imaging.py, so I added --ignore-errors for the Docker jobs to work around it.

[hugovk]

Thank you!