Merge pull request #3869 from 10up/fix/issue-3699

Major refactor of the Term::format_args() method and conditionally set search fields for term queries in REST API requests.

includes/classes/Indexable/Term/QueryIntegration.php

@@ -53,6 +53,8 @@ public function __construct( $indexable_slug = 'term' ) {
 
 		// Filter term query
 		add_filter( 'terms_pre_query', [ $this, 'maybe_filter_query' ], 10, 2 );
+
+		add_filter( 'rest_post_tag_query', [ $this, 'maybe_set_search_fields' ], 10, 2 );
 	}
 
 	/**
@@ -241,6 +243,27 @@ public function maybe_filter_query( $results, WP_Term_Query $query ) {
 		return $new_terms;
 	}
 
+	/**
+	 * Conditionally set search fields for term queries in REST API requests.
+	 *
+	 * If in an REST API request that came from WordPress edit screen, do not search for term description.
+	 *
+	 * @param array           $prepared_args Array of arguments for get_terms().
+	 * @param WP_REST_Request $request       The REST API request.
+	 * @return array
+	 */
+	public function maybe_set_search_fields( $prepared_args, $request ) {
+		$referer = $request->get_header( 'referer' );
+
+		if ( empty( $referer ) || ! preg_match( '/post\.php\?post=([0-9]*)&action=edit/', $referer ) ) {
+			return $prepared_args;
+		}
+
+		$prepared_args['search_fields'] = [ 'name', 'slug' ];
+
+		return $prepared_args;
+	}
+
 	/**
 	 * Format the ES hits/results as term objects.
 	 *