GH-37310: [Python][CI] Enable warnings in PyArrow pytests

[danepitkin]

Rationale for this change

Warnings are enabled for some nightly jobs, but not for CI jobs. This is not helpful since devs typically rely on the CI job as part of the PR process.

What changes are included in this PR?

• Enable warnings as errors in PR CI
• Remove warnings as errors in Hypothesis tests, which has no PR CI

Are these changes tested?

Will be tested as part of CI.

Are there any user-facing changes?

This affects the dev workflow.

• Closes: [Python][CI] Enable warnings as errors in pytests for CI jobs #37310

[github-actions]

⚠️ GitHub issue #37310 has been automatically assigned in GitHub to PR creator.

[jorisvandenbossche]

We could also leave it out here, and focus on getting no warnings on only linux?

[danepitkin]

I went ahead and suppressed the single warning, which does have an open issue to resolve. Since not everyone has a mac to debug this, maybe it's better to leave it out though?

[jorisvandenbossche]

I would personally leave it out (I think enabling this for a smaller subset of builds will be easier to maintain)

[danepitkin]

Sounds good! I'll update

[danepitkin]

Ready to merge!

[raulcd]

Maybe late to the party but is there any reason we don't enable it by default when running tests?
https://github.com/apache/arrow/blob/main/ci/scripts/python_test.sh#L62
Maybe it would be better to explicitly disable if we require on a specific job instead of enabling it everywhere?

[danepitkin]

Maybe late to the party but is there any reason we don't enable it by default when running tests? https://github.com/apache/arrow/blob/main/ci/scripts/python_test.sh#L62 Maybe it would be better to explicitly disable if we require on a specific job instead of enabling it everywhere?

Good question! A lot of the integration/testing with old versions or with 3rd party packages on their latest development branch can typically throw a lot of warnings. We have many of these jobs so it might actually be more work to disable all of them then to enable for the ones we want.

[danepitkin]

I rebased just now to make sure no new warnings are introduced before merging.

[danepitkin]

Closing for now. It would need to be redone after rebasing so may warrant a new PR at that point.