[shail-mehta]

What

Trac ticket: #65819

Makes the data provider in tests/phpunit/tests/cache.php static.

Why

PHPUnit data providers should be static so they do not depend on test instance state and remain compatible with current PHPUnit usage in Core.

How

• Convert data_is_valid_key() to public static

Test-only; no production code changes.

Testing Instructions

1. npm run test:php -- --filter Tests_Cache
2. npm run test:php -- --filter Tests_Cache -c tests/phpunit/multisite.xml
3. npm run test:php -- --filter Tests_Cache --order-by=random
4. npm run test:php -- --group cache

Use of AI Tools

• Cursor

[Copilot]

🟢 Approval recommended

The provider uses only literal data, so the static declaration preserves behavior without depending on test instance state.

No open issues 🎉

What changed in this PR

Makes the cache test data provider static to align with current PHPUnit usage in WordPress Core. This is a test-only change with no production impact.

Changes:

• Converts data_is_valid_key() to public static, preserving its test data and existing provider reference.

File	Description
tests/​phpunit/​tests/​cache.php	Makes the cache key validation data provider static.

_{Review effort: Balanced}