From 41532d5638063762e93e03f9bc5283dd6897e31a Mon Sep 17 00:00:00 2001
From: Pascal Birchler <pascal.birchler@gmail.com>
Date: Sat, 17 Feb 2024 15:28:04 +0000
Subject: [PATCH] Interactivity API: Skip instead of bail out if HTML contains
 `SVG` or `MATH`.

Addresses an issue with server-side processing of directives when there is e.g. an SVG icon a navigation menu.

Props cbravobernal, westonruter, dmsnell, swissspidy.
Fixes #60517.
Built from https://develop.svn.wordpress.org/trunk@57649


git-svn-id: http://core.svn.wordpress.org/trunk@57150 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 ...interactivity-api-directives-processor.php | 33 +++++++++++++++++++
 .../class-wp-interactivity-api.php            |  9 +++--
 wp-includes/version.php                       |  2 +-
 3 files changed, 41 insertions(+), 3 deletions(-)

diff --git a/wp-includes/interactivity-api/class-wp-interactivity-api-directives-processor.php b/wp-includes/interactivity-api/class-wp-interactivity-api-directives-processor.php
index 24201e82fd..3b2dcb1237 100644
--- a/wp-includes/interactivity-api/class-wp-interactivity-api-directives-processor.php
+++ b/wp-includes/interactivity-api/class-wp-interactivity-api-directives-processor.php
@@ -180,6 +180,39 @@ final class WP_Interactivity_API_Directives_Processor extends WP_HTML_Tag_Proces
 		return array( $opener_tag, $closer_tag );
 	}
 
+	/**
+	 * Skips processing the content between tags.
+	 *
+	 * It positions the cursor in the closer tag of the foreign element, if it
+	 * exists.
+	 *
+	 * This function is intended to skip processing SVG and MathML inner content
+	 * instead of bailing out the whole processing.
+	 *
+	 * @since 6.5.0
+	 *
+	 * @access private
+	 *
+	 * @return bool Whether the foreign content was successfully skipped.
+	 */
+	public function skip_to_tag_closer(): bool {
+		$depth    = 1;
+		$tag_name = $this->get_tag();
+		while ( $depth > 0 && $this->next_tag(
+			array(
+				'tag_name'    => $tag_name,
+				'tag_closers' => 'visit',
+			)
+		) ) {
+			if ( $this->has_self_closing_flag() ) {
+				continue;
+			}
+			$depth += $this->is_tag_closer() ? -1 : 1;
+		}
+
+		return 0 === $depth;
+	}
+
 	/**
 	 * Finds the matching closing tag for an opening tag.
 	 *
diff --git a/wp-includes/interactivity-api/class-wp-interactivity-api.php b/wp-includes/interactivity-api/class-wp-interactivity-api.php
index 536b6623e2..9e5b1be1fa 100644
--- a/wp-includes/interactivity-api/class-wp-interactivity-api.php
+++ b/wp-includes/interactivity-api/class-wp-interactivity-api.php
@@ -235,9 +235,14 @@ final class WP_Interactivity_API {
 		while ( $p->next_tag( array( 'tag_closers' => 'visit' ) ) ) {
 			$tag_name = $p->get_tag();
 
+			/*
+			 * Directives inside SVG and MATH tags are not processed,
+			 * as they are not compatible with the Tag Processor yet.
+			 * We still process the rest of the HTML.
+			 */
 			if ( 'SVG' === $tag_name || 'MATH' === $tag_name ) {
-				$unbalanced = true;
-				break;
+				$p->skip_to_tag_closer();
+				continue;
 			}
 
 			if ( $p->is_tag_closer() ) {
diff --git a/wp-includes/version.php b/wp-includes/version.php
index ddcb7b75cd..6d9f86df82 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.5-beta1-57648';
+$wp_version = '6.5-beta1-57649';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.