Build/Test Tools: Flag slow PHPUnit tests with annotations

[lancewillett]

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

What this changes

Adds a Flag slow PHPUnit tests step to the canonical PHP 8.5 report job. It parses the JUnit report and, for tests over a threshold (default 1s), emits GitHub Actions warning annotations and a run-summary table naming the slowest tests. Runs on pull requests and pushes to trunk.

This complements #13083: those six CodeVitals aggregates store the trend but cannot name a test. This one names the slow ones, so a PR author can spot a slow test they added.

Behavior

• Advisory only: runs even on failed test runs (always()) and never fails the build (continue-on-error).
• Inline annotations capped at 10 (GitHub's per-step limit); the summary table lists more.
• Container-absolute paths normalized to repository-relative so annotations resolve.
• A testcase without timing data (e.g. a skipped test) is ignored, not an error.

Use of AI Tools

AI assistance: Yes
Tool(s): Codex (via Claude Code), hardened with an adversarial multi-lens review
Used for: drafting the workflow step and PHP script, and reviewing it before submission.

[github-actions]

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[github-actions]

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[Copilot]

Pull request overview

This PR adds CI tooling to surface individual slow PHPUnit tests during GitHub Actions runs by parsing the generated JUnit report and emitting GitHub Actions warning annotations plus a step-summary Markdown table, targeting the canonical PHP 8.5 reporting job context.

Changes:

• Added a new PHP CLI script to parse junit.xml, identify tests exceeding a configurable threshold, and emit warning annotations and a run summary.
• Integrated a new “Flag slow PHPUnit tests” step into the reusable PHPUnit workflow (gated to PHP 8.5 + reporting-enabled runs on PRs and trunk pushes).

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
tests/phpunit/prepare-slow-test-annotations.php	New CLI parser that finds slow testcases in JUnit XML and outputs GitHub Actions annotations + a step summary table.
.github/workflows/reusable-phpunit-tests-v3.yml	Adds a workflow step that runs the new parser after the main PHPUnit run under the intended conditions.

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[adimoldovan]

One PHPCS error fails the build. The rest are small.

Two points that map to no line in the diff:

1. #13083 adds class-wp-phpunit-timing-metrics.php, which streams the same junit.xml at the same point in the same workflow. Once it lands, this script should reuse it rather than walk the file a second time.
2. The job's # Performs the following steps: list (lines 110-129) omits this step. #13083 updates that list for its own step.

[lancewillett]

Direct review fixes are in ac5472e. One architectural follow-up remains: #13083 is still open. Once it lands, I’ll update this branch to share its JUnit traversal instead of opening the report twice.

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_{Adversarial review · gpt-5}