Ticket #45800: 45800.2.diff

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

@@ -379 +379 @@
                         $this->meta_query_clauses = $this->meta_query->get_sql( 'comment', $wpdb->comments, 'comment_ID', $this );
                 }
 
-                /*
-                 * Only use the args defined in the query_var_defaults to compute the key,
-                 * but ignore 'fields', which does not affect query results.
-                 */
-                $_args = wp_array_slice_assoc( $this->query_vars, array_keys( $this->query_var_defaults ) );
-                unset( $_args['fields'] );
+                $comment_ids = null;
+
+                /**
+                 * Filter the comments array before the query takes place.
+                 *
+                 * Return a non-null value to bypass WordPress's default comment queries.
+                 *
+                 *
+                 * @since 5.3.0
+                 *
+                 * @param array|null    $comment_ids Return an array of comment data to short-circuit WP's comment query,
+                 *                                or null to allow WP to run its normal queries.
+                 * @param WP_Comment_Query $this The WP_Comment_Query instance, passed by reference.
+                 */
+                $comment_ids = apply_filters_ref_array( 'comments_pre_query', array( $comment_ids, &$this ) );
+
+                if ( null === $comment_ids ) {
+                        /*
+                         * Only use the args defined in the query_var_defaults to compute the key,
+                         * but ignore 'fields', which does not affect query results.
+                         */
+                        $_args = wp_array_slice_assoc( $this->query_vars, array_keys( $this->query_var_defaults ) );
+                        unset( $_args['fields'] );
 
-                $key          = md5( serialize( $_args ) );
-                $last_changed = wp_cache_get_last_changed( 'comment' );
+                        $key          = md5( serialize( $_args ) );
+                        $last_changed = wp_cache_get_last_changed( 'comment' );
 
-                $cache_key   = "get_comments:$key:$last_changed";
-                $cache_value = wp_cache_get( $cache_key, 'comment' );
-                if ( false === $cache_value ) {
-                        $comment_ids = $this->get_comment_ids();
-                        if ( $comment_ids ) {
-                                $this->set_found_comments();
-                        }
+                        $cache_key   = "get_comments:$key:$last_changed";
+                        $cache_value = wp_cache_get( $cache_key, 'comment' );
+                        if ( false === $cache_value ) {
+                                $comment_ids = $this->get_comment_ids();
+                                if ( $comment_ids ) {
+                                        $this->set_found_comments();
+                                }
 
-                        $cache_value = array(
-                                'comment_ids'    => $comment_ids,
-                                'found_comments' => $this->found_comments,
-                        );
-                        wp_cache_add( $cache_key, $cache_value, 'comment' );
-                } else {
-                        $comment_ids          = $cache_value['comment_ids'];
-                        $this->found_comments = $cache_value['found_comments'];
+                                $cache_value = array(
+                                        'comment_ids'    => $comment_ids,
+                                        'found_comments' => $this->found_comments,
+                                );
+                                wp_cache_add( $cache_key, $cache_value, 'comment' );
+                        } else {
+                                $comment_ids          = $cache_value['comment_ids'];
+                                $this->found_comments = $cache_value['found_comments'];
+                        }
                 }
-
                 if ( $this->found_comments && $this->query_vars['number'] ) {
                         $this->max_num_pages = ceil( $this->found_comments / $this->query_vars['number'] );
                 }

tests/phpunit/tests/comment/query.php

@@ -4882 +4882 @@
 
                 $this->assertEqualSets( $c1, $found );
         }
+
+        /**
+         * @ticket 45800
+         */
+        public function test_comments_pre_query_filter_should_bypass_database_query() {
+                global $wpdb;
+
+                add_filter( 'comments_pre_query', array( __CLASS__, 'filter_comments_pre_query' ), 10, 2 );
+
+                $num_queries = $wpdb->num_queries;
+
+                $q       = new WP_Comment_Query();
+                $results = $q->query(
+                        array(
+                                'fields' => 'ids',
+                        )
+                );
+
+                remove_filter( 'comments_pre_query', array( __CLASS__, 'filter_comments_pre_query' ), 10, 2 );
+
+                // Make sure no queries were executed.
+                $this->assertSame( $num_queries, $wpdb->num_queries );
+
+                // We manually inserted a non-existing site and overrode the results with it.
+                $this->assertSame( array( 555 ), $q->comments );
+
+                // Make sure manually setting total_users doesn't get overwritten.
+                $this->assertEquals( 1, $q->found_comments );
+        }
+
+        public static function filter_comments_pre_query( $comments, $query ) {
+                $query->found_comments = 1;
+
+                return array( 555 );
+        }
 }