From 63e73fb860583495890487d6ae8bf938a8c5c8e7 Mon Sep 17 00:00:00 2001
From: spacedmonkey <spacedmonkey@git.wordpress.org>
Date: Tue, 7 Feb 2023 12:10:18 +0000
Subject: [PATCH] Taxonomy: Implement `wp_cache_get_multiple` in
 `wp_queue_posts_for_term_meta_lazyload`.

In [47938] the `wp_cache_get_multiple` function was added to core. This function allows for multiple cache keys to be received from cache in a single function call. `wp_queue_posts_for_term_meta_lazyload` function does many calls to cache. To get taxonomy relationship for multiple posts and get all terms. Replace calls to `get_object_term_cache` with calls to `wp_cache_get_multiple` and `_prime_term_caches`. This improves performance on sites that implement the `wp_cache_get_multiple` in their object caching drop-in.

Props spacedmonkey, ocean90, SergeyBiryukov, costdev, flixos90, joemcgill, 10upsimon.
Fixes #57150.
Built from https://develop.svn.wordpress.org/trunk@55252


git-svn-id: http://core.svn.wordpress.org/trunk@54785 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-includes/class-wp-query.php |  2 ++
 wp-includes/post.php           | 50 +++++++++++++++++++++++++++++-----
 wp-includes/version.php        |  2 +-
 3 files changed, 46 insertions(+), 8 deletions(-)

diff --git a/wp-includes/class-wp-query.php b/wp-includes/class-wp-query.php
index 2e1f2f8b57..e33fa7904f 100644
--- a/wp-includes/class-wp-query.php
+++ b/wp-includes/class-wp-query.php
@@ -1948,6 +1948,8 @@ class WP_Query {
 
 		if ( ! isset( $q['lazy_load_term_meta'] ) ) {
 			$q['lazy_load_term_meta'] = $q['update_post_term_cache'];
+		} elseif ( $q['lazy_load_term_meta'] ) { // Lazy loading term meta only works if term caches are primed.
+			$q['update_post_term_cache'] = true;
 		}
 
 		if ( ! isset( $q['update_post_meta_cache'] ) ) {
diff --git a/wp-includes/post.php b/wp-includes/post.php
index d9460d7838..f4423dcd66 100644
--- a/wp-includes/post.php
+++ b/wp-includes/post.php
@@ -7779,7 +7779,7 @@ function wp_delete_auto_drafts() {
  */
 function wp_queue_posts_for_term_meta_lazyload( $posts ) {
 	$post_type_taxonomies = array();
-	$term_ids             = array();
+	$prime_post_terms     = array();
 	foreach ( $posts as $post ) {
 		if ( ! ( $post instanceof WP_Post ) ) {
 			continue;
@@ -7790,16 +7790,52 @@ function wp_queue_posts_for_term_meta_lazyload( $posts ) {
 		}
 
 		foreach ( $post_type_taxonomies[ $post->post_type ] 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 ( ! in_array( $term->term_id, $term_ids, true ) ) {
-						$term_ids[] = $term->term_id;
+			$prime_post_terms[ $taxonomy ][] = $post->ID;
+		}
+	}
+
+	$term_ids = array();
+	if ( $prime_post_terms ) {
+		$prime_term_ids     = array();
+		$prime_taxonomy_ids = array();
+		foreach ( $prime_post_terms as $taxonomy => $post_ids ) {
+			$cached_term_ids = wp_cache_get_multiple( $post_ids, "{$taxonomy}_relationships" );
+			if ( is_array( $cached_term_ids ) ) {
+				$cached_term_ids = array_filter( $cached_term_ids );
+				foreach ( $cached_term_ids as $term_ids ) {
+					// Backward compatibility for if a plugin is putting objects into the cache, rather than IDs.
+					foreach ( $term_ids as $term_id ) {
+						if ( is_numeric( $term_id ) ) {
+							$prime_term_ids[]                  = (int) $term_id;
+							$prime_taxonomy_ids[ $taxonomy ][] = (int) $term_id;
+						} elseif ( isset( $term_id->term_id ) ) {
+							$prime_taxonomy_ids[ $taxonomy ][] = (int) $term_id->term_id;
+							$prime_term_ids[]                  = (int) $term_id->term_id;
+						}
 					}
 				}
 			}
 		}
+
+		if ( $prime_term_ids ) {
+			$prime_term_ids = array_unique( $prime_term_ids );
+			// Do not prime term meta at this point, let the lazy loader take care of that.
+			_prime_term_caches( $prime_term_ids, false );
+
+			foreach ( $prime_taxonomy_ids as $taxonomy => $_term_ids ) {
+				foreach ( $_term_ids as $term_id ) {
+					if ( in_array( $term_id, $term_ids, true ) ) {
+						continue;
+					}
+					$term = get_term( $term_id, $taxonomy );
+					if ( is_wp_error( $term ) ) {
+						continue;
+					}
+
+					$term_ids[] = $term_id;
+				}
+			}
+		}
 	}
 
 	if ( $term_ids ) {
diff --git a/wp-includes/version.php b/wp-includes/version.php
index e4b6731449..8acc20a0c0 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.2-alpha-55251';
+$wp_version = '6.2-alpha-55252';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.