--doctest-modules runs __main__ files

[max-sixty]

• a detailed description of the bug or suggestion
• output of pip list from the virtual environment you are using
• pytest and operating system versions: pytest 5.4.1, MacOS
• minimal example if possible

As per this SO question, pytest will run __main__.py files when passed --doctest-modules, even though it avoids them when collecting tests without that flag.

Is that intentional?

[FrozenBob]

pytest normally avoids __main__.py files not because of any specific __main__.py handling, but simply because the name __main__.py doesn't match the test_*.py or *_test.py patterns pytest looks for.

That said, __main__.py files are typically not considered modules, and even multiprocessing doesn't expect __main__.py files to have an if __name__ == '__main__' guard. Importing __main__.py is questionable behavior. Plus, --doctest-modules already avoids setup.py, which is a very similar case.

[Zac-HD]

Closing this because it's been answered (and inactive for more than two weeks) 😄

[max-sixty]

@Zac-HD that wasn't exactly my interpretation of @FrozenBob 's response — though possibly I'm not understanding it fully — I interpreted their response as "Yes it's likely not correct behavior for pytest to import __main__.py"

While I think this is still a relevant issue, you know this better than I do, so feel free to close if you have other reasons to close.

Thanks as ever

[Zac-HD]

No, sorry, I should have read this more closely - I think you're right, and we should probably change this (though I haven't investigated in depth).

[nicoddemus]

Fixed by #8949