From 0fce77da25bf780ced29b67a916bab788182f32f Mon Sep 17 00:00:00 2001
From: Boone Gorges <boonebgorges@gmail.com>
Date: Thu, 12 Oct 2017 14:59:47 +0000
Subject: [PATCH] Invalidate comment query cache when modifying comment meta.

Comment queries are sensitive to comment meta due to the `meta_query`
parameter, so the cache must be invalidated when comment meta is changed,
added, or deleted.

Props spacedmonkey.
See #40669.
Built from https://develop.svn.wordpress.org/trunk@41848


git-svn-id: http://core.svn.wordpress.org/trunk@41682 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-includes/comment.php | 18 +++++++++++++++---
 wp-includes/version.php |  2 +-
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/wp-includes/comment.php b/wp-includes/comment.php
index c015fea4f2..9054e1acee 100644
--- a/wp-includes/comment.php
+++ b/wp-includes/comment.php
@@ -423,7 +423,11 @@ function get_comment_count( $post_id = 0 ) {
  * @return int|bool Meta ID on success, false on failure.
  */
 function add_comment_meta($comment_id, $meta_key, $meta_value, $unique = false) {
-	return add_metadata('comment', $comment_id, $meta_key, $meta_value, $unique);
+	$added = add_metadata( 'comment', $comment_id, $meta_key, $meta_value, $unique );
+	if ( $added ) {
+		wp_cache_set( 'last_changed', microtime(), 'comment' );
+	}
+	return $added;
 }
 
 /**
@@ -442,7 +446,11 @@ function add_comment_meta($comment_id, $meta_key, $meta_value, $unique = false)
  * @return bool True on success, false on failure.
  */
 function delete_comment_meta($comment_id, $meta_key, $meta_value = '') {
-	return delete_metadata('comment', $comment_id, $meta_key, $meta_value);
+	$deleted = delete_metadata( 'comment', $comment_id, $meta_key, $meta_value );
+	if ( $deleted ) {
+		wp_cache_set( 'last_changed', microtime(), 'comment' );
+	}
+	return $deleted;
 }
 
 /**
@@ -479,7 +487,11 @@ function get_comment_meta($comment_id, $key = '', $single = false) {
  * @return int|bool Meta ID if the key didn't exist, true on successful update, false on failure.
  */
 function update_comment_meta($comment_id, $meta_key, $meta_value, $prev_value = '') {
-	return update_metadata('comment', $comment_id, $meta_key, $meta_value, $prev_value);
+	$updated = update_metadata( 'comment', $comment_id, $meta_key, $meta_value, $prev_value );
+	if ( $updated ) {
+		wp_cache_set( 'last_changed', microtime(), 'comment' );
+	}
+	return $updated;
 }
 
 /**
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 13ff4a66d2..6d545f3877 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.9-beta2-41847';
+$wp_version = '4.9-beta2-41848';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.