Repair wp/5.9 branch Actions: Pin phpunit/phpunit to a PHP 5.6/7.0-compatible release - #619

What?

• Lowers the phpunit/phpunit dev dependency from ^8.5 to ^5.7 (resolves to 5.7.27), so the PHP 5.6 unit test jobs can load the plugin's Composer autoloader.
• Changes config.platform.php from 8.1 to 5.6.20, and ignores four Composer advisories, so that version can resolve.
• Regenerates composer.lock with composer update phpunit/phpunit --with-all-dependencies.

Why?

Both PHP 5.6 jobs fail before any test runs:

Parse error: syntax error, unexpected ':', expecting ';' or '{' in .../vendor/phpunit/phpunit/src/Runner/Version.php on line 34

wp-phpunit/wp-phpunit calls class_exists( 'PHPUnit\Runner\Version' ), which loads the class from the locked phpunit/phpunit 8.5.21. Its return type declarations don't parse on PHP 5.6. PHPUnit 5.7.27 has no namespaced PHPUnit\Runner\Version, so the check returns false and wp-phpunit falls back to PHPUnit_Runner_Version.

wp/6.0 makes the same change in WordPress#84281. This branch also needs:

• config.platform.php 5.6.20: PHPUnit 5.7 requires PHP ^5.6 || ^7.0, so it can't resolve against the 8.1 set in Repair wp/5.9 branch Actions: Let the current Composer release install this branch's dependencies #341. 5.6.20 is the matrix's lowest PHP version and Repair wp/5.9 branch Actions: Let the current Composer release install this branch's dependencies #341's require.php floor. With 7.4, Composer would pick symfony/yaml and symfony/polyfill-ctype releases that need PHP 7.1+. The platform change can't go in Repair wp/5.9 branch Actions: Let the current Composer release install this branch's dependencies #341, because PHPUnit ^8.5 needs PHP 7.2+.
• Advisory ignores: PKSA-z3gr-8qht-p93v matches every phpunit/phpunit below 8.5.52, and PKSA-v5yj-8nmz-sk2q, PKSA-ft77-7h5f-p3r6 and PKSA-b14r-zh1d-vdrc match every symfony/yaml 2.x–4.x, which PHPUnit 5.7 requires. The reasons recorded are the same as on wp/6.0.

How?

Only phpunit/phpunit's dependency tree changes in composer.lock: 22 packages updated, phpunit/phpunit-mock-objects 3.4.4 and symfony/yaml v3.4.47 added, and five phar-io/sebastian/theseer packages removed. wp-phpunit/wp-phpunit 5.9.17, yoast/phpunit-polyfills, composer/installers and the PHPCS packages keep their versions.

The PHP 7.4, 8.0 and 8.1 jobs use the PHPUnit bundled in their Docker image, not the one in vendor.

Testing

• composer update with Composer 2.10.3 resolves as above, and composer install --no-interaction succeeds.
• On PHP 5.6 and 7.0, every file in vendor/composer/autoload_files.php and PHPUnit's Runner/Version.php passes php -l. class_exists( 'PHPUnit\Runner\Version' ) returns false, and PHPUnit_Runner_Version::id() returns 5.7.27.

Use of AI Tools

This PR was created by Claude Code under my supervision. All code should be treated as AI-produced and not yet reviewed by a human until this PR is marked Ready for Review.

🤖 Generated with Claude Code