WordPress · dmsnell · Dec 13, 2023 · Dec 20, 2023 · Dec 20, 2023 · Dec 20, 2023
@@ -72,7 +72,7 @@ function gutenberg_render_background_support( $block_content, $block ) {
 
 	if ( ! empty( $styles['css'] ) ) {
 		// Inject background styles to the first element, presuming it's the wrapper, if it exists.
-		$tags = new WP_HTML_Tag_Processor( $block_content );
+		$tags = new Gutenberg_HTML_Tag_Processor_6_5( $block_content );
 
 		if ( $tags->next_tag() ) {
 			$existing_style = $tags->get_attribute( 'style' );

@@ -80,7 +80,7 @@ function gutenberg_render_behaviors_support_lightbox( $block_content, $block ) {
 		return $block_content;
 	}
 
-	$processor = new WP_HTML_Tag_Processor( $block_content );
+	$processor = new Gutenberg_HTML_Tag_Processor_6_5( $block_content );
 
 	$aria_label = __( 'Enlarge image', 'gutenberg' );
 
@@ -123,7 +123,7 @@ function gutenberg_render_behaviors_support_lightbox( $block_content, $block ) {
 		$scale_attr = false;
 	}
 
-	$w = new WP_HTML_Tag_Processor( $block_content );
+	$w = new Gutenberg_HTML_Tag_Processor_6_5( $block_content );
 	$w->next_tag( 'figure' );
 	$w->add_class( 'wp-lightbox-container' );
 	$w->set_attribute( 'data-wp-interactive', true );
@@ -184,7 +184,7 @@ function gutenberg_render_behaviors_support_lightbox( $block_content, $block ) {
 	// image is a copy of the one in the body, which animates immediately
 	// as the lightbox is opened, while the enlarged one is a full-sized
 	// version that will likely still be loading as the animation begins.
-	$m = new WP_HTML_Tag_Processor( $block_content );
+	$m = new Gutenberg_HTML_Tag_Processor_6_5( $block_content );
 	$m->next_tag( 'figure' );
 	$m->add_class( 'responsive-image' );
 	$m->next_tag( 'img' );
@@ -200,7 +200,7 @@ function gutenberg_render_behaviors_support_lightbox( $block_content, $block ) {
 	$m->set_attribute( 'data-wp-style--object-fit', 'selectors.core.image.lightboxObjectFit' );
 	$initial_image_content = $m->get_updated_html();
 
-	$q = new WP_HTML_Tag_Processor( $block_content );
+	$q = new Gutenberg_HTML_Tag_Processor_6_5( $block_content );
 	$q->next_tag( 'figure' );
 	$q->add_class( 'enlarged-image' );
 	$q->next_tag( 'img' );

@@ -89,7 +89,7 @@ function gutenberg_render_elements_support( $block_content, $block ) {
 				 * contains a single wrapper and that it's the first element in the
 				 * rendered output. That first element, if it exists, gets the class.
 				 */
-				$tags = new WP_HTML_Tag_Processor( $block_content );
+				$tags = new Gutenberg_HTML_Tag_Processor_6_5( $block_content );
 				if ( $tags->next_tag() ) {
 					$tags->add_class( wp_get_elements_class_name( $block ) );
 				}

@@ -599,7 +599,7 @@ function gutenberg_render_layout_support_flag( $block_content, $block ) {
 	}
 
 	// Prep the processor for modifying the block output.
-	$processor = new WP_HTML_Tag_Processor( $block_content );
+	$processor = new Gutenberg_HTML_Tag_Processor_6_5( $block_content );
 
 	// Having no tags implies there are no tags onto which to add class names.
 	if ( ! $processor->next_tag() ) {
@@ -793,7 +793,7 @@ function gutenberg_render_layout_support_flag( $block_content, $block ) {
 	$inner_block_wrapper_classes = null;
 	$first_chunk                 = $block['innerContent'][0] ?? null;
 	if ( is_string( $first_chunk ) && count( $block['innerContent'] ) > 1 ) {
-		$first_chunk_processor = new WP_HTML_Tag_Processor( $first_chunk );
+		$first_chunk_processor = new Gutenberg_HTML_Tag_Processor_6_5( $first_chunk );
 		while ( $first_chunk_processor->next_tag() ) {
 			$class_attribute = $first_chunk_processor->get_attribute( 'class' );
 			if ( is_string( $class_attribute ) && ! empty( $class_attribute ) ) {
@@ -874,7 +874,7 @@ function gutenberg_restore_group_inner_container( $block_content, $block ) {
 	 * have to be removed from the outer wrapper and then added to the inner.
 	*/
 	$layout_classes = array();
-	$processor      = new WP_HTML_Tag_Processor( $block_content );
+	$processor      = new Gutenberg_HTML_Tag_Processor_6_5( $block_content );
 
 	if ( $processor->next_tag( array( 'class_name' => 'wp-block-group' ) ) ) {
 		if ( method_exists( $processor, 'class_list' ) ) {
@@ -917,7 +917,7 @@ static function ( $matches ) {
 
 	// Add layout classes to inner wrapper.
 	if ( ! empty( $layout_classes ) ) {
-		$processor = new WP_HTML_Tag_Processor( $updated_content );
+		$processor = new Gutenberg_HTML_Tag_Processor_6_5( $updated_content );
 		if ( $processor->next_tag( array( 'class_name' => 'wp-block-group__inner-container' ) ) ) {
 			foreach ( $layout_classes as $class_name ) {
 				$processor->add_class( $class_name );

@@ -123,7 +123,7 @@ function gutenberg_render_position_support( $block_content, $block ) {
 		);
 
 		// Inject class name to block container markup.
-		$content = new WP_HTML_Tag_Processor( $block_content );
+		$content = new Gutenberg_HTML_Tag_Processor_6_5( $block_content );
 		$content->next_tag();
 		foreach ( $wrapper_classes as $class ) {
 			$content->add_class( $class );

@@ -33,7 +33,7 @@ function _gutenberg_add_block_level_presets_class( $block_content, $block ) {
 
 	// Like the layout hook this assumes the hook only applies to blocks with a single wrapper.
 	// Add the class name to the first element, presuming it's the wrapper, if it exists.
-	$tags = new WP_HTML_Tag_Processor( $block_content );
+	$tags = new Gutenberg_HTML_Tag_Processor_6_5( $block_content );
 	if ( $tags->next_tag() ) {
 		$tags->add_class( _wp_get_presets_class_name( $block ) );
 	}

@@ -892,7 +892,7 @@ public static function render_duotone_support( $block_content, $block ) {
 		}
 
 		// Like the layout hook, this assumes the hook only applies to blocks with a single wrapper.
-		$tags = new WP_HTML_Tag_Processor( $block_content );
+		$tags = new Gutenberg_HTML_Tag_Processor_6_5( $block_content );
 		if ( $tags->next_tag() ) {
 			$tags->add_class( $filter_id );
 		}

@@ -0,0 +1,187 @@
+<?php
+/**
+ * HTML API: WP_HTML_Active_Formatting_Elements class
+ *
+ * @package WordPress
+ * @subpackage HTML-API
+ * @since 6.4.0
+ */
+
+/**
+ * Core class used by the HTML processor during HTML parsing
+ * for managing the stack of active formatting elements.
+ *
+ * This class is designed for internal use by the HTML processor.
+ *
+ * > Initially, the list of active formatting elements is empty.
+ * > It is used to handle mis-nested formatting element tags.
+ * >
+ * > The list contains elements in the formatting category, and markers.
+ * > The markers are inserted when entering applet, object, marquee,
+ * > template, td, th, and caption elements, and are used to prevent
+ * > formatting from "leaking" into applet, object, marquee, template,
+ * > td, th, and caption elements.
+ * >
+ * > In addition, each element in the list of active formatting elements
+ * > is associated with the token for which it was created, so that
+ * > further elements can be created for that token if necessary.
+ *
+ * @since 6.4.0
+ *
+ * @access private
+ *
+ * @see https://html.spec.whatwg.org/#list-of-active-formatting-elements
+ * @see WP_HTML_Processor
+ */
+class Gutenberg_HTML_Active_Formatting_Elements_6_5 {
+	/**
+	 * Holds the stack of active formatting element references.
+	 *
+	 * @since 6.4.0
+	 *
+	 * @var WP_HTML_Token[]
+	 */
+	private $stack = array();
+
+	/**
+	 * Reports if a specific node is in the stack of active formatting elements.
+	 *
+	 * @since 6.4.0
+	 *
+	 * @param WP_HTML_Token $token Look for this node in the stack.
+	 * @return bool Whether the referenced node is in the stack of active formatting elements.
+	 */
+	public function contains_node( $token ) {
+		foreach ( $this->walk_up() as $item ) {
+			if ( $token->bookmark_name === $item->bookmark_name ) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
+	/**
+	 * Returns how many nodes are currently in the stack of active formatting elements.
+	 *
+	 * @since 6.4.0
+	 *
+	 * @return int How many node are in the stack of active formatting elements.
+	 */
+	public function count() {
+		return count( $this->stack );
+	}
+
+	/**
+	 * Returns the node at the end of the stack of active formatting elements,
+	 * if one exists. If the stack is empty, returns null.
+	 *
+	 * @since 6.4.0
+	 *
+	 * @return WP_HTML_Token|null Last node in the stack of active formatting elements, if one exists, otherwise null.
+	 */
+	public function current_node() {
+		$current_node = end( $this->stack );
+
+		return $current_node ? $current_node : null;
+	}
+
+	/**
+	 * Pushes a node onto the stack of active formatting elements.
+	 *
+	 * @since 6.4.0
+	 *
+	 * @see https://html.spec.whatwg.org/#push-onto-the-list-of-active-formatting-elements
+	 *
+	 * @param WP_HTML_Token $token Push this node onto the stack.
+	 */
+	public function push( $token ) {
+		/*
+		 * > If there are already three elements in the list of active formatting elements after the last marker,
+		 * > if any, or anywhere in the list if there are no markers, that have the same tag name, namespace, and
+		 * > attributes as element, then remove the earliest such element from the list of active formatting
+		 * > elements. For these purposes, the attributes must be compared as they were when the elements were
+		 * > created by the parser; two elements have the same attributes if all their parsed attributes can be
+		 * > paired such that the two attributes in each pair have identical names, namespaces, and values
+		 * > (the order of the attributes does not matter).
+		 *
+		 * @todo Implement the "Noah's Ark clause" to only add up to three of any given kind of formatting elements to the stack.
+		 */
+		// > Add element to the list of active formatting elements.
+		$this->stack[] = $token;
+	}
+
+	/**
+	 * Removes a node from the stack of active formatting elements.
+	 *
+	 * @since 6.4.0
+	 *
+	 * @param WP_HTML_Token $token Remove this node from the stack, if it's there already.
+	 * @return bool Whether the node was found and removed from the stack of active formatting elements.
+	 */
+	public function remove_node( $token ) {
+		foreach ( $this->walk_up() as $position_from_end => $item ) {
+			if ( $token->bookmark_name !== $item->bookmark_name ) {
+				continue;
+			}
+
+			$position_from_start = $this->count() - $position_from_end - 1;
+			array_splice( $this->stack, $position_from_start, 1 );
+			return true;
+		}
+
+		return false;
+	}
+
+	/**
+	 * Steps through the stack of active formatting elements, starting with the
+	 * top element (added first) and walking downwards to the one added last.
+	 *
+	 * This generator function is designed to be used inside a "foreach" loop.
+	 *
+	 * Example:
+	 *
+	 *     $html = '<em><strong><a>We are here';
+	 *     foreach ( $stack->walk_down() as $node ) {
+	 *         echo "{$node->node_name} -> ";
+	 *     }
+	 *     > EM -> STRONG -> A ->
+	 *
+	 * To start with the most-recently added element and walk towards the top,
+	 * see WP_HTML_Active_Formatting_Elements::walk_up().
+	 *
+	 * @since 6.4.0
+	 */
+	public function walk_down() {
+		$count = count( $this->stack );
+
+		for ( $i = 0; $i < $count; $i++ ) {
+			yield $this->stack[ $i ];
+		}
+	}
+
+	/**
+	 * Steps through the stack of active formatting elements, starting with the
+	 * bottom element (added last) and walking upwards to the one added first.
+	 *
+	 * This generator function is designed to be used inside a "foreach" loop.
+	 *
+	 * Example:
+	 *
+	 *     $html = '<em><strong><a>We are here';
+	 *     foreach ( $stack->walk_up() as $node ) {
+	 *         echo "{$node->node_name} -> ";
+	 *     }
+	 *     > A -> STRONG -> EM ->
+	 *
+	 * To start with the first added element and walk towards the bottom,
+	 * see WP_HTML_Active_Formatting_Elements::walk_down().
+	 *
+	 * @since 6.4.0
+	 */
+	public function walk_up() {
+		for ( $i = count( $this->stack ) - 1; $i >= 0; $i-- ) {
+			yield $this->stack[ $i ];
+		}
+	}
+}