Reintroduce PytestReturnNotNoneWarning

[nicoddemus]

Since this warning is meant to be permanent, added proper documentation to the assert section in the docs.

Fixes #13477

[nicoddemus]

Do we consider this a bugfix that is OK to enter in the next patch release, or should we wait for 8.5?

[RonnyPfannschmidt]

We should backport as we correct a regression

[nicoddemus]

I'm getting the same failure on main locally.

Testing main on https://github.com/pytest-dev/pytest/pull/13496 to confirm the failure is unrelated to these changes.

[nicoddemus]

Blocked by https://github.com/pytest-dev/pytest/issues/13497, will wait for us to fix that before merging this.

[RonnyPfannschmidt]

The related issue is possibly something larger to fix so id prefer we dont block on it

[nicoddemus]

Apologies if this comment is off the mark, but do we need to separately handle the await case (https://github.com/pytest-dev/pytest/issues/11372) that was the original rationale for changing the warning to an error?

If I understand correctly your question, no. The state of affairs will be:

• async tests will always fail if not handled by a plugin.
• Normal tests will always generate a warning if they return non-None.

[patchback[bot]]

Backport to 8.4.x: 💚 backport PR created

✅ Backport PR branch: patchback/backports/8.4.x/53f05c44d9530c4ac5ce5804ef75fe61713d46d8/pr-13495

Backported as https://github.com/pytest-dev/pytest/pull/13527

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