Ticket #38034: class-wp-query.diff

src/wp-includes/class-wp-query.php

@@ -1494 +1494 @@
                 $allowed_keys = array(
                         'post_name', 'post_author', 'post_date', 'post_title', 'post_modified',
                         'post_parent', 'post_type', 'name', 'author', 'date', 'title', 'modified',
-                        'parent', 'type', 'ID', 'menu_order', 'comment_count', 'rand',
+                        'parent', 'type', 'ID', 'menu_order', 'comment_count', 'rand', 'post__in',
                 );
 
                 $primary_meta_key = '';
@@ -1552 +1552 @@
                         case 'meta_value_num':
                                 $orderby_clause = "{$primary_meta_query['alias']}.meta_value+0";
                                 break;
+                        case 'post__in':
+                                if( !empty( $this->query_vars['post__in'] ) ) {
+                                        $orderby_clause = "FIELD({$this->db->posts}.ID," . implode( ',', array_map( 'absint', $this->query_vars['post__in'] ) ) . ")";
+                                }
+                                break;
                         default:
                                 if ( array_key_exists( $orderby, $meta_clauses ) ) {
                                         // $orderby corresponds to a meta_query clause.
@@ -2143 +2148 @@
                         }
                 } elseif ( 'none' == $q['orderby'] ) {
                         $orderby = '';
-                } elseif ( $q['orderby'] == 'post__in' && ! empty( $post__in ) ) {
-                        $orderby = "FIELD( {$this->db->posts}.ID, $post__in )";
                 } elseif ( $q['orderby'] == 'post_parent__in' && ! empty( $post_parent__in ) ) {
                         $orderby = "FIELD( {$this->db->posts}.post_parent, $post_parent__in )";
                 } elseif ( $q['orderby'] == 'post_name__in' && ! empty( $post_name__in ) ) {