Tests: Add a separate PHPUnit configuration file for PHPUnit 10.1 and later

[robelsust]

Introduces separate PHPUnit 10.1+ configuration files (phpunit10.xml.dist and tests/phpunit/multisite10.xml) alongside the existing PHPUnit 9 configuration files (phpunit.xml.dist and tests/phpunit/multisite.xml), fulfilling Problem 1 of Trac #62004 as scoped in Trac #66210.

Background & Context

• In PHPUnit 10.0 and 10.1, the XML configuration schema changed significantly. Attributes on the root <phpunit> element (convertErrorsToExceptions, convertWarningsToExceptions, convertNoticesToExceptions, convertDeprecationsToExceptions) were removed.
• PHP native deprecations, notices, and warnings are now configured via failOnDeprecation="true", failOnNotice="true", failOnWarning="true", failOnRisky="true", and the corresponding displayDetailsOnTestsThatTrigger*="true" attributes.
• The <filter><whitelist> element was replaced by <source><include> and <source><exclude>.
• The <logging><log type="junit" target="..."/></logging> element was replaced by <logging><junit outputFile="..."/></logging>.
• Because WordPress Core trunk must continue to support PHPUnit 9 for PHP 7.4 while supporting PHPUnit 10.1+ on newer PHP versions, separate configuration files are needed.

Changes

1. Added phpunit10.xml.dist:

   • Conforms to PHPUnit 10.1+ XML Schema (https://schema.phpunit.de/10.1/phpunit.xsd).
   • Configures failOnDeprecation="true", failOnNotice="true", failOnWarning="true", failOnRisky="true", and details display.
   • Migrates code coverage path definitions into <source><include> and <source><exclude>.
   • Modernizes logging to <logging><junit outputFile="tests/phpunit/build/logs/junit.xml" />.

2. Added tests/phpunit/multisite10.xml:

   • The PHPUnit 10.1+ multisite counterpart to tests/phpunit/multisite.xml.
   • Sets WP_TESTS_MULTISITE="1" and WP_RUN_CORE_TESTS="1".
   • Excludes the appropriate test groups (ajax, ms-files, ms-excluded, external-http, oembed-headers, html-api-web-platform-tests).
   • Configures <source> paths relative to tests/phpunit/.

3. Workflow & CI Automation:

   • reusable-phpunit-tests-v3.yml: Added a Select PHPUnit configuration step before running tests that detects the installed PHPUnit version inside the container. If PHPUnit version >= 10, it automatically switches PHPUNIT_CONFIG to phpunit10.xml.dist (or tests/phpunit/multisite10.xml when testing multisite).
   • reusable-phpunit-tests-v1.yml & reusable-phpunit-tests-v2.yml: Fixed the external-http test step which previously hard-coded -c phpunit.xml.dist, now correctly using -c "${PHPUNIT_CONFIG}".
   • Path Triggers: Updated .github/workflows/phpunit-tests.yml, phpunit-tests-full-matrix.yml, and test-coverage.yml to trigger on phpunit10.xml.dist and multisite10.xml, while excluding !phpunit10.xml.dist from asset/e2e/performance workflows.

4. Developer Tooling & Documentation:

   • composer.json: Added "test10": [ "Composer\\Config::disableProcessTimeout", "@php ./vendor/phpunit/phpunit/phpunit -c phpunit10.xml.dist" ].
   • package.json: Added "test:php10": "node ./tools/local-env/scripts/docker.js run --rm php ./vendor/bin/phpunit -c phpunit10.xml.dist".
   • .gitignore: Added /phpunit10.xml and /phpunit-10.xml to ignore local developer overrides.
   • tests/phpunit/README.md: Added a Configuration Files section documenting which configuration file to use for PHPUnit 9 vs PHPUnit 10+.

Verification

• Both phpunit10.xml.dist and tests/phpunit/multisite10.xml were strictly validated against official PHPUnit 10.1, 10.5, and 11.0 XSD schemas via xmllint --noout --schema with 0 errors.
• composer validate executed with 0 errors.
• package.json syntax validated.
• Existing PHPUnit test suite confirmed running without regressions under PHPUnit 9.

Trac ticket: https://core.trac.wordpress.org/ticket/66210

Use of AI Tools

AI assistance: Yes
Tool(s): Antigravity
Model(s): Gemini
Used for: Validating schema conformity against PHPUnit 10.1/10.5/11.0 XSD specifications, updating CI workflow configuration detection and reusable test runner workflows, and authoring developer documentation. All changes were reviewed, verified, and validated locally.

---

This Pull Request is for code review only. Please keep all other discussion in the Trac ticket. Do not merge this Pull Request. See GitHub Pull Requests for Code Review in the Core Handbook for more details.

[github-actions]

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Props therssoftware, lancewillett.

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[github-actions]

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[lancewillett]

The separate configurations fit the ticket’s scope. Please address three integration gaps before landing:

1. In reusable-phpunit-tests-v3.yml, remove or version-gate --verbose and -v. PHPUnit 10 rejects these options; I reproduced Unknown option "--verbose" with PHPUnit 10.5.60 in Docker.
2. Pass -c "${PHPUNIT_CONFIG}" to the xDebug test step too. It currently bypasses the new configuration selection.
3. Restore JUnit logging in tests/phpunit/multisite10.xml, matching the existing multisite configuration:

   <logging>
       <junit outputFile="build/logs/junit.xml" />
   </logging>

   This preserves the output consumed by CI reporting and timing tools.

Both XML files passed PHPUnit 10.1 schema validation, and isolated PHPUnit 10 probes confirmed that their settings fail on deprecations, notices, and warnings. Actionlint passed. CI is green, but the inspected PHP 8.5 job uses PHPUnit 9.6, so it does not exercise the new configuration.

These are focused configuration/invocation fixes; completing the broader PHPUnit 10 migration can remain separate.

_{AI review · gpt-6}

[robelsust]

Thanks for the thorough review and catching these integration gaps @lancewillett!

I have addressed all three items in commit 479ae87f56:

1. Removed --verbose and -v in reusable-phpunit-tests-v3.yml: Removed from all test invocation steps (external-http, main tests, ajax, ms-files, and xdebug) to resolve the PHPUnit 10 Unknown option "--verbose" error.
2. Passed -c "${PHPUNIT_CONFIG}" to Xdebug tests: The Run (Xdebug) tests step now uses -c "${PHPUNIT_CONFIG}" so it respects the dynamic PHPUnit 10+ configuration selection.
3. Restored JUnit logging in tests/phpunit/multisite10.xml: Added <logging><junit outputFile="build/logs/junit.xml" /></logging> matching tests/phpunit/multisite.xml. Both XML files re-validated cleanly against PHPUnit 10.1, 10.5, and 11.0 schemas.