test on free‑threaded Python

[Saransh-cpp]

Description

Following #675, this PR adds test for free-threaded Python 3.14

Checklist

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't any other open Pull Requests for the required change?
• Does your submission pass pre-commit? ($ pre-commit run --all-files or $ nox -s lint)
• Does your submission pass tests? ($ pytest or $ nox -s tests)
• Does the documentation build with your changes? ($ cd docs; make clean; make html or $ nox -s docs)
• Does your submission pass the doctests? ($ pytest --doctest-plus src/vector/ or $ nox -s doctests)

Before Merging

• Summarize the commit messages into a brief review of the Pull request.

[ikrommyd]

@Saransh-cpp numba does not yet support free-threaded python FYI. I think they plan to do it in their next release.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.70%. Comparing base (fd1a553) to head (4c83a86).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #676   +/-   ##
=======================================
  Coverage   86.70%   86.70%           
=======================================
  Files          96       96           
  Lines       11221    11221           
=======================================
  Hits         9729     9729           
  Misses       1492     1492           

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[Saransh-cpp]

I see that Numba is not fully available on python 3.14t yet. @henryiii is there a neat way to exclude the installation of Numba when running on Python 3.14t? Or should I just manipulate the dependency-groups and isolate Numba as a stand-alone dependency-group (making them a bit ugly but functional).

Edit: Thanks, @ikrommyd! Yes, I realised that. There is no metadata marker to exclude dependencies from a specific build of Python; hence, I do have an ugly fix in mind, but I wanted to check if there is a more elegant way to do this.

[henryiii]

Yes, no elegant way, sadly. There needs to be a new marker, and they want to have a more elegant solution than just a free-threading specific marker, so it pretty much stalled AFAIK.

Numba does technically support 3.14t now, but only preliminary and no wheels as far as I know. numba/numba#9928

[ikrommyd]

Yeah I knew there are no wheels and hence why I approved the other PR. I did not consider free-threaded builds since I knew vector depends on numba. Should have been more careful since it is not a strict dependency.

[Saransh-cpp]

This should now be ready for a review.

[ikrommyd]

Good to see that no test failures popped up.

[henryiii]

Should we add a free-threading classifier? :)

[Saransh-cpp]

Ooh yes, sounds nice. I've added the Programming Language :: Python :: Free Threading :: 3 - Stable classifier. Thanks!

[ianna]

@Saransh-cpp - this looks great! Thanks for adding it.