[fabiomsnunes]

Context

• Fixes TypeError in Post_Republisher::clean_up_when_copy_manually_deleted() when the post is already gone (concurrent deletes) #563: Post_Republisher::clean_up_when_copy_manually_deleted() re-fetches the post with get_post() on before_delete_post and passes the result to Permissions_Helper::is_rewrite_and_republish_copy( WP_Post $post ). When another request deleted the same post first, get_post() returns null and the request dies with a TypeError.

Summary

This PR can be summarized in the following changelog entry:

• Fixes a bug where a fatal error occurred when the same post was deleted by two requests at the same time.

Relevant technical choices:

• The callback now receives the WP_Post that wp_delete_post() already passes as the 2nd argument of before_delete_post (10, 2), so it no longer depends on the row still being in the database.
• $post is optional and the method falls back to get_post() when it is not passed, so direct callers using only the post ID keep working. The instanceof WP_Post check covers that fallback returning null.
• The new integration test calls the method directly instead of going through wp_delete_post(): with a real concurrent delete, core's own _reset_front_page_settings_for_post() (also on before_delete_post) emits a PHP warning for the same reason, which PHPUnit turns into an error.
• I don't have permission to add labels: this needs changelog: bugfix.

Test instructions

Test instructions for the acceptance test before the PR gets merged

This PR can be acceptance tested by following these steps:

• On trunk, with only Duplicate Post active, save this as repro.php and run wp eval-file repro.php. It simulates a concurrent request deleting the post right before this request's before_delete_post callbacks run:

<?php
$post_id = wp_insert_post( [ 'post_title' => 'raced', 'post_status' => 'publish' ] );

$simulate_concurrent_delete = function ( $id ) use ( &$simulate_concurrent_delete ) {
	global $wpdb;
	remove_action( 'before_delete_post', $simulate_concurrent_delete, 1 );
	$wpdb->delete( $wpdb->posts, [ 'ID' => $id ] );
	clean_post_cache( $id );
};
add_action( 'before_delete_post', $simulate_concurrent_delete, 1 );

wp_delete_post( $post_id, true );

• See the fatal error TypeError: ... is_rewrite_and_republish_copy(): Argument #1 ($post) must be of type WP_Post, null given.
• Switch to this branch and run the script again: no fatal error (core may still log a PHP warning from _reset_front_page_settings_for_post(), see above).
• Regression check for Rewrite & Republish: create a Rewrite & Republish copy of a post, move the copy to the trash and delete it permanently, then open the original post: the notice about an existing Rewrite & Republish copy is gone and a new Rewrite & Republish copy can be created.

Relevant test scenarios

• Changes should be tested with the browser console open
• Changes should be tested on different posts/pages/taxonomies/custom post types/custom taxonomies
• Changes should be tested on different editors (Default Block/Gutenberg/Classic/Elementor/other)
• Changes should be tested on different browsers
• Changes should be tested on multisite

Test instructions for QA when the code is in the RC

• QA should use the same steps as above.

QA can test this PR by following these steps:

• Same steps as above.

Impact check

This PR affects the following parts of the plugin, which may require extra testing:

• Rewrite & Republish: cleaning up the original post's flag when its copy is permanently deleted.

UI changes

• This PR changes the UI in the plugin. I have added the 'UI change' label to this PR.

Documentation

• I have written documentation for this change. For example, comments in the Relevant technical choices, comments in the code, documentation on Confluence / shared Google Drive / Yoast developer portal, or other.

Quality assurance

• I have tested this code to the best of my abilities

Checks run locally: composer lint, composer test, composer check-cs-thresholds (57/57 errors, 0/0 warnings, same as trunk) and composer test-wp-env. The integration tests ran with --php=8.4, because composer update on my PHP 8.4 host installs a doctrine/instantiator that doesn't parse on the default PHP 8.2 container. The new unit and integration tests fail on trunk with the TypeError and pass on this branch.