[hmbashar]

Summary

Adds tests for code of the Abilities API classes that no test runs, according to the Codecov report.

WP_Ability

• An unknown property is reported with _doing_it_wrong() and ignored.
• The category is required (missing, empty, null, integer and array).
• Input is rejected with ability_missing_input_schema when the ability has no input schema.
• The wp_ability_validate_input and wp_ability_validate_output filters can reject with false (Invalid input. / Invalid output.).
• An ability of a custom class without an execute callback returns ability_invalid_execute_callback.
• A permission callback that returns a WP_Error is reported with _doing_it_wrong() and its reason is not shown to the caller.
• The ability cannot be serialized or unserialized.

Registries and category

• WP_Abilities_Registry and WP_Ability_Categories_Registry cannot be serialized or unserialized.
• WP_Ability_Categories_Registry::get_instance() returns null before init, and creates the registry once and fires wp_abilities_api_categories_init.
• WP_Ability_Category throws for an empty slug.

Testing

vendor/bin/phpunit --filter 'Tests_Abilities_API_WpAbility::'
vendor/bin/phpunit --filter 'Tests_Abilities_API_WpAbilitiesRegistry::'
vendor/bin/phpunit --filter 'Tests_Abilities_API_WpAbilityCategoryRegistry::'
vendor/bin/phpunit -c tests/phpunit/multisite.xml --filter 'Tests_Abilities_API_'
vendor/bin/phpcs tests/phpunit/tests/abilities-api/

Mutation check: 24 changes to the source (conditions, error codes and messages, the throw of __sleep() and __wakeup(), the init check, the action and the instance creation) were each caught by a test.

Trac ticket: https://core.trac.wordpress.org/ticket/66549

Use of AI Tools

AI assistance: Yes
Tool(s): Claude Code
Model(s): Claude Sonnet 5.5
Used for: Written with AI and manually reviewed by me.

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Props hmbashar.

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