Taxonomy: Allow filtering Ajax term search results in quick edit.

This changeset introduces the `ajax_term_search_results` hook which can be used to filter the term search results returned by the AJAX term query.

Props grandeljay, costdev, ironprogrammer, audrasjb, SergeyBiryukov.
Fixes #55606.


git-svn-id: https://develop.svn.wordpress.org/trunk@53781 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/includes/ajax-actions.php

@@ -162,6 +162,17 @@ function wp_ajax_ajax_tag_search() {
 		)
 	);
 
+	/**
+	 * Filters the Ajax term search results.
+	 *
+	 * @since 6.1.0
+	 *
+	 * @param string[]    $results Array of term names.
+	 * @param WP_Taxonomy $tax     The taxonomy object.
+	 * @param string      $s       The search term.
+	 */
+	$results = apply_filters( 'ajax_term_search_results', $results, $tax, $s );
+
 	echo implode( "\n", $results );
 	wp_die();
 }

tests/phpunit/tests/ajax/TagSearch.php

@@ -158,4 +158,38 @@ class Tests_Ajax_TagSearch extends WP_Ajax_UnitTestCase {
 		$this->_handleAjax( 'ajax-tag-search' );
 	}
 
+	/**
+	 * Test the ajax_term_search_results filter
+	 *
+	 * @ticket 55606
+	 */
+	public function test_ajax_term_search_results_filter() {
+
+		// Become an administrator.
+		$this->_setRole( 'administrator' );
+
+		// Set up a default request.
+		$_GET['tax'] = 'post_tag';
+		$_GET['q']   = 'chat';
+
+		// Add the ajax_term_search_results filter.
+		add_filter(
+			'ajax_term_search_results',
+			static function( $results, $tax, $s ) {
+				return array( 'ajax_term_search_results was applied' );
+			},
+			10,
+			3
+		);
+
+		// Make the request.
+		try {
+			$this->_handleAjax( 'ajax-tag-search', $_GET['tax'], $_GET['q'] );
+		} catch ( WPAjaxDieContinueException $e ) {
+			unset( $e );
+		}
+
+		// Ensure we found the right match.
+		$this->assertSame( 'ajax_term_search_results was applied', $this->_last_response );
+	}
 }