From 4bfba3516953ab9a27ce4007302613d68ef66d59 Mon Sep 17 00:00:00 2001
From: Felix Arntz <felix-arntz@leaves-and-love.net>
Date: Tue, 12 Sep 2023 19:20:21 +0000
Subject: [PATCH] Posts, Post Types: Avoid unnecessarily parsing blocks twice
 in `wp_trim_excerpt()`.

All blocks relevant for the excerpt are already being parsed in `excerpt_remove_blocks()`. Therefore running `do_blocks()` on the post content only to create the excerpt is unnecessary and wasteful from a performance perspective.

Props thekt12, spacedmonkey, mukesh27, joemcgill.
Fixes #58682.

Built from https://develop.svn.wordpress.org/trunk@56560


git-svn-id: http://core.svn.wordpress.org/trunk@56072 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-includes/blocks.php     |  4 ++++
 wp-includes/formatting.php | 17 ++++++++++++++---
 wp-includes/version.php    |  2 +-
 3 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/wp-includes/blocks.php b/wp-includes/blocks.php
index 3c88f7b4c3..7795a6969b 100644
--- a/wp-includes/blocks.php
+++ b/wp-includes/blocks.php
@@ -956,6 +956,10 @@ function filter_block_kses_value( $value, $allowed_html, $allowed_protocols = ar
  * @return string The parsed and filtered content.
  */
 function excerpt_remove_blocks( $content ) {
+	if ( ! has_blocks( $content ) ) {
+		return $content;
+	}
+
 	$allowed_inner_blocks = array(
 		// Classic blocks have their blockName set to null.
 		null,
diff --git a/wp-includes/formatting.php b/wp-includes/formatting.php
index 05084329d3..0e5797fa7e 100644
--- a/wp-includes/formatting.php
+++ b/wp-includes/formatting.php
@@ -3980,18 +3980,29 @@ function wp_trim_excerpt( $text = '', $post = null ) {
 		 * within the excerpt are stripped out. Modifying the tags here
 		 * is wasteful and can lead to bugs in the image counting logic.
 		 */
-		$filter_removed = remove_filter( 'the_content', 'wp_filter_content_tags' );
+		$filter_image_removed = remove_filter( 'the_content', 'wp_filter_content_tags' );
+
+		/*
+		 * Temporarily unhook do_blocks() since excerpt_remove_blocks( $text )
+		 * handels block rendering needed for excerpt.
+		 */
+		$filter_block_removed = remove_filter( 'the_content', 'do_blocks', 9 );
 
 		/** This filter is documented in wp-includes/post-template.php */
 		$text = apply_filters( 'the_content', $text );
 		$text = str_replace( ']]>', ']]&gt;', $text );
 
-		/**
+		// Restore the original filter if removed.
+		if ( $filter_block_removed ) {
+			add_filter( 'the_content', 'do_blocks', 9 );
+		}
+
+		/*
 		 * Only restore the filter callback if it was removed above. The logic
 		 * to unhook and restore only applies on the default priority of 10,
 		 * which is generally used for the filter callback in WordPress core.
 		 */
-		if ( $filter_removed ) {
+		if ( $filter_image_removed ) {
 			add_filter( 'the_content', 'wp_filter_content_tags' );
 		}
 
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 8d2df4d68f..ccbb89a59a 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.4-alpha-56559';
+$wp_version = '6.4-alpha-56560';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.