In get_bookmarks(), don't cache if 'orderby=rand'.

Props lukecavanagh, prettyboymp, c3mdigital, MikeHansenMe.
Fixes #18356.

git-svn-id: https://develop.svn.wordpress.org/trunk@37565 602fd350-edb4-49c9-b593-d223f7449a82

Author: boonebgorges

src/wp-includes/bookmark.php

@@ -128,7 +128,8 @@ function get_bookmarks( $args = '' ) {
 	$r = wp_parse_args( $args, $defaults );
 
 	$key = md5( serialize( $r ) );
-	if ( $cache = wp_cache_get( 'get_bookmarks', 'bookmark' ) ) {
+	$cache = false;
+	if ( 'rand' !== $r['orderby'] && $cache = wp_cache_get( 'get_bookmarks', 'bookmark' ) ) {
 		if ( is_array( $cache ) && isset( $cache[ $key ] ) ) {
 			$bookmarks = $cache[ $key ];
 			/**
@@ -285,8 +286,10 @@ function get_bookmarks( $args = '' ) {
 
 	$results = $wpdb->get_results( $query );
 
-	$cache[ $key ] = $results;
-	wp_cache_set( 'get_bookmarks', $cache, 'bookmark' );
+	if ( 'rand()' !== $orderby ) {
+		$cache[ $key ] = $results;
+		wp_cache_set( 'get_bookmarks', $cache, 'bookmark' );
+	}
 
 	/** This filter is documented in wp-includes/bookmark.php */
 	return apply_filters( 'get_bookmarks', $results, $r );

tests/phpunit/tests/bookmark/getBookmarks.php

@@ -47,4 +47,27 @@ public function test_adding_bookmark_should_bust_get_bookmarks_cache() {
 		$this->assertEqualSets( $bookmarks, wp_list_pluck( $found2, 'link_id' ) );
 		$this->assertTrue( $num_queries < $wpdb->num_queries );
 	}
+
+	/**
+	 * @ticket 18356
+	 */
+	public function test_orderby_rand_should_not_be_cached() {
+		global $wpdb;
+
+		$bookmarks = self::factory()->bookmark->create_many( 2 );
+
+		$found1 = get_bookmarks( array(
+			'orderby' => 'rand',
+		) );
+
+		$num_queries = $wpdb->num_queries;
+
+		$found2 = get_bookmarks( array(
+			'orderby' => 'rand',
+		) );
+
+		// equal sets != same order
+		$this->assertEqualSets( $found1, $found2 );
+		$this->assertTrue( $num_queries < $wpdb->num_queries );
+	}
 }