add_marker with usefixtures no longer works with pytest 8.0.0

[rhshadrach]

I believe this may be related to #3664.

In pandas, we dynamically add a marker for our doctests so that we don't need import pandas as pd and import numpy as np in every docstring.

https://github.com/pandas-dev/pandas/blob/9008ee5810c09bc907b5fdc36fc3c1dff4a50c55/pandas/conftest.py#L191-L198

The add_doctest_imports fixture is here.

https://github.com/pandas-dev/pandas/blob/9008ee5810c09bc907b5fdc36fc3c1dff4a50c55/pandas/conftest.py#L253-L259

With pytest 8.0.0, add_marker no longer has any effect. Is the intentional, and if so, is there an alternative?

[bluetech]

Very similar to #11759. Would the alternative described there of using an autouse fixture instead of the hook work for pandas?

[rhshadrach]

Thanks! There is a comment in the pandas code that we don't use autouse because of perf. I'll see if I can track down the history there and see if I can reproduce the perf issue.

[rhshadrach]

This was originally changed in pandas in pandas-dev/pandas#45667. It tried undoing that patch locally, seeing negligible differences in runtimes for the test suite. Will see what it looks like on the pandas CI in pandas-dev/pandas#57122.

[mroeschke]

It would be nice if an alternative to an autouse fixture could be used in the future as non-doctests don't need this fixture at all (which is probably +98% of tests in pandas).

The prior motivation for doing this dynamically was me being curious why in the durations output the last-ran unit test TEARDOWN could be one of the longest durations, and removing an autouse=True, doctest_namespace fixture was the culprit.