BUG: Need to be able to specify location of legacy files for tests

[opoplawski]

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Reproducible Example

When building pandas for Fedora, we build a wheel and install it to a temporary location, then run tests using using that location:

/usr/bin/pytest -v /builddir/build/BUILD/python-pandas-3.0.1-build/BUILDROOT/usr/lib64/python3.14/site-packages/pandas 

This fails with:

______________ ERROR collecting tests/io/pytables/test_compat.py _______________
Empty parameter set in 'test_legacy_files' at line 86

This is because the legacy .h5 files are not in the installed location (which is fine, we don't want that).

Issue Description

Would it be possible to specify the location of the .h5 files?

Expected Behavior

Test finds the files it needs

Installed Versions

3.0.1

[rhshadrach]

Thanks for the report. A few questions:

1. Is this only the .h5 files giving you trouble?
2. Do you actually want to run these .h5 tests, or would skipping them satisfy as well?
3. If you're planning on putting the .h5 files somewhere, why not in tests/io/data/legacy_hdf/?

[Julian901]

Thanks for the report. A few questions:

1. Is this only the .h5 files giving you trouble?
2. Do you actually want to run these .h5 tests, or would skipping them satisfy as well?
3. If you're planning on putting the .h5 files somewhere, why not in tests/io/data/legacy_hdf/?

To answer your questions:

1. From what I can tell, yes - only the .h5 files cause this issue since test_compat.py uses a module-level glob to find them.
2. Skipping seems like the right behavior when files are not present - failing with Empty parameter set is confusing and unhelpful.
3. The issue is specifically for packagers (e.g. Fedora) who build a wheel and run tests against the installed location, where legacy data files are intentionally not included.

I've opened a PR that makes the test skip gracefully when no .h5 files are found: #64680