Build/Test Tools: Preserve PHPUnit timing results for use in metrics

[lancewillett]

Trac ticket: https://core.trac.wordpress.org/ticket/65887

What this changes

The PHPUnit workflow uploads the existing JUnit report after every push to trunk from one canonical job:

• PHP 8.5;
• MySQL 8.4;
• single site;
• default domain and cache configuration.

The upload happens immediately after the main test suite, before later test-group runs replace the configured JUnit file.

Each trunk push produces one artifact named phpunit-timing-results. The artifact contains junit.xml with per-test timing data. Other events and matrix jobs do not upload timing artifacts.

Why one artifact

One stable environment provides comparable results and the raw data needed to find slow tests. Collecting every test segment from every matrix job adds storage, naming, and analysis work without helping the first use case.

GitHub uses the repository default retention period. CodeVitals and aggregate trend reporting are handled separately in #13083.

How to validate

An end-to-end test temporarily allowed PR #13070 to run the upload step from the canonical job:

• workflow run 31969896671;
• PHP 8.5/MySQL 8.4 test-reporting job;
• phpunit-timing-results artifact.

The downloaded artifact contained an 8,909,462-byte, well-formed junit.xml file with timing for 30,871 test cases. The final condition limits uploads to pushes on trunk.

After merge, open the latest trunk push:

https://github.com/WordPress/wordpress-develop/actions/workflows/phpunit-tests.yml?query=event%3Apush+branch%3Atrunk

The Artifacts section should contain phpunit-timing-results. Download it with GitHub CLI:

gh run download <run-id> --repo WordPress/wordpress-develop --name phpunit-timing-results

Reviewers can confirm that the existing configuration creates the uploaded file:

npm run test:php -- --filter Tests_Functions::test_wp_parse_args_object
test -s tests/phpunit/build/logs/junit.xml

Testing

• actionlint passed.
• The targeted PHPUnit command above passed with one test and two assertions and wrote its timing to junit.xml.
• The end-to-end test uploaded, downloaded, and parsed phpunit-timing-results successfully.

[lancewillett]

End-to-end artifact validation passed.

The canonical PHPUnit job temporarily allowed the pull request event to exercise the exact upload step:

• Workflow run 31969896671
• PHP 8.5/MySQL 8.4 test-reporting job
• phpunit-timing-results artifact

The downloaded artifact contained a well-formed, 8,909,462-byte junit.xml file with timing for 30,871 test cases. The upload and download both completed successfully.

Commit 8ccbcd4 restored the scheduled-only condition after the test. The final workflow also passed actionlint, and zizmor reported zero findings.

[github-actions]

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Props lancewillett, desrosj.

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[lancewillett]

3ff9c19 addresses review feedback.

We are limiting the metrics to trunk runs to prove the concept before adding all PR commits which can come later. For now, they'd add more storage and might not create an apples-to-apples comparison for an early look at slow tests.