Ticket #34047: 34047.2.diff

src/wp-includes/default-filters.php

@@ -201 +201 @@
 add_filter( 'xmlrpc_pingback_error',    'xmlrpc_pingback_error'               );
 add_filter( 'title_save_pre',           'trim'                                );
 add_filter( 'get_comment_metadata',     'wp_lazyload_comment_meta',     10, 2 );
-add_filter( 'get_term_metadata',        'wp_lazyload_term_meta',        10, 2 );
 
 add_filter( 'http_request_host_is_external', 'allowed_http_request_hosts', 10, 2 );
 

src/wp-includes/query.php

@@ -3540 +3540 @@
                 if ( $this->posts )
                         $this->posts = array_map( 'get_post', $this->posts );
 
+
+                if ( $q['update_post_term_cache'] ) {
+                        add_action( 'get_term_metadata', array( $this, 'lazyload_term_meta' ), 10, 2 );
+                }
+
                 if ( ! $q['suppress_filters'] ) {
                         /**
                          * Filter the raw post results array, prior to status checks.
@@ -4716 +4721 @@
                         $this->setup_postdata( $this->post );
                 }
         }
+
+        /**
+         * Lazy-loads termmeta for located posts.
+         *
+         * As a rule, term queries (`get_terms()` and `wp_get_object_terms()`) prime the metadata cache for matched
+         * terms by default. However, this can cause a slight performance penalty, especially when that metadata is
+         * not actually used. In the context of a `WP_Query` instance, we're able to avoid this potential penalty.
+         * `update_object_term_cache()`, called from `update_post_caches()`, does not 'update_term_meta_cache'.
+         * Instead, the first time `get_term_meta()` is called from within a `WP_Query` loop, the current method
+         * detects the fact, and then primes the metadata cache for all terms attached to all posts in the loop,
+         * with a single database query.
+         *
+         * This method is public so that it can be used as a filter callback. As a rule, there is no need to invoke it
+         * directly, from either inside or outside the `WP_Query` object.
+         *
+         * @since 4.4.0
+         * @access public
+         *
+         * @param null $check   The `$check` param passed from the 'pre_term_metadata' hook.
+         * @param int  $term_id ID of the term whose metadata is being cached.
+         * @return mixed In order not to short-circuit `get_metadata()`. Generally, this is `null`, but it could be
+         *               another value if filtered by a plugin.
+         */
+        public function lazyload_term_meta( $check, $term_id ) {
+                // We can only lazyload if the entire post object is present.
+                $posts = array();
+                foreach ( $this->posts as $post ) {
+                        if ( $post instanceof WP_Post ) {
+                                $posts[] = $post;
+                        }
+                }
+
+                if ( ! empty( $posts ) ) {
+                        // Fetch cached term_ids for each post. Keyed by term_id for faster lookup.
+                        $term_ids = array();
+                        foreach ( $posts as $post ) {
+                                $taxonomies = get_object_taxonomies( $post->post_type );
+                                foreach ( $taxonomies as $taxonomy ) {
+                                        // Term cache should already be primed by 'update_post_term_cache'.
+                                        $terms = get_object_term_cache( $post->ID, $taxonomy );
+                                        if ( false !== $terms ) {
+                                                foreach ( $terms as $term ) {
+                                                        if ( ! isset( $term_ids[ $term->term_id ] ) ) {
+                                                                $term_ids[ $term->term_id ] = 1;
+                                                        }
+                                                }
+                                        }
+                                }
+                        }
+
+                        if ( $term_ids ) {
+                                update_termmeta_cache( array_keys( $term_ids ) );
+                        }
+                }
+
+                // We only do this once per `WP_Query` instance.
+                remove_action( 'get_term_metadata', array( $this, 'lazyload_term_meta' ), 10, 2 );
+                return $check;
+        }
 }
 
 /**

src/wp-includes/taxonomy-functions.php

@@ -1576 +1576 @@
 }
 
 /**
- * Lazy-loads termmeta when inside of a `WP_Query` loop.
- *
- * As a rule, term queries (`get_terms()` and `wp_get_object_terms()`) prime the metadata cache for matched terms by
- * default. However, this can cause a slight performance penalty, especially when that metadata is not actually used.
- * In the context of a `WP_Query` loop, we're able to avoid this potential penalty. `update_object_term_cache()`,
- * called from `update_post_caches()`, does not 'update_term_meta_cache'. Instead, the first time `get_term_meta()` is
- * called from within a `WP_Query` loop, the current function detects the fact, and then primes the metadata cache for
- * all terms attached to all posts in the loop, with a single database query.
- *
- * @since 4.4.0
- *
- * @param null $check   The `$check` param passed from the 'pre_term_metadata' hook.
- * @param int  $term_id ID of the term whose metadata is being cached.
- * @return null In order not to short-circuit `get_metadata()`.
- */
-function wp_lazyload_term_meta( $check, $term_id ) {
-        global $wp_query;
-
-        if ( $wp_query instanceof WP_Query && ! empty( $wp_query->posts ) && $wp_query->get( 'update_post_term_cache' ) ) {
-                // We can only lazyload if the entire post object is present.
-                $posts = array();
-                foreach ( $wp_query->posts as $post ) {
-                        if ( $post instanceof WP_Post ) {
-                                $posts[] = $post;
-                        }
-                }
-
-                if ( empty( $posts ) ) {
-                        return;
-                }
-
-                // Fetch cached term_ids for each post. Keyed by term_id for faster lookup.
-                $term_ids = array();
-                foreach ( $posts as $post ) {
-                        $taxonomies = get_object_taxonomies( $post->post_type );
-                        foreach ( $taxonomies as $taxonomy ) {
-                                // No extra queries. Term cache should already be primed by 'update_post_term_cache'.
-                                $terms = get_object_term_cache( $post->ID, $taxonomy );
-                                if ( false !== $terms ) {
-                                        foreach ( $terms as $term ) {
-                                                if ( ! isset( $term_ids[ $term->term_id ] ) ) {
-                                                        $term_ids[ $term->term_id ] = 1;
-                                                }
-                                        }
-                                }
-                        }
-                }
-
-                if ( $term_ids ) {
-                        update_termmeta_cache( array_keys( $term_ids ) );
-                }
-        }
-
-        return $check;
-}
-
-/**
  * Check if Term exists.
  *
  * Formerly is_term(), introduced in 2.3.0.