HTML API: Add current_node_is() helper method to stack of open elem…

…ents.

As part of work to add more spec support to the HTML API, this new method
will make it easier to implement the logic when in the SELECT and TABLE
insertion modes.

Developed in #6968
Discussed in https://core.trac.wordpress.org/ticket/51576

Props dmsnell, jonsurrell.
See #61576.


git-svn-id: https://develop.svn.wordpress.org/trunk@58676 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/html-api/class-wp-html-open-elements.php

@@ -144,6 +144,48 @@ public function current_node() {
 		return $current_node ? $current_node : null;
 	}
 
+	/**
+	 * Indicates if the current node is of a given type or name.
+	 *
+	 * It's possible to pass either a node type or a node name to this function.
+	 * In the case there is no current element it will always return `false`.
+	 *
+	 * Example:
+	 *
+	 *     // Is the current node a text node?
+	 *     $stack->current_node_is( '#text' );
+	 *
+	 *     // Is the current node a DIV element?
+	 *     $stack->current_node_is( 'DIV' );
+	 *
+	 *     // Is the current node any element/tag?
+	 *     $stack->current_node_is( '#tag' );
+	 *
+	 * @see WP_HTML_Tag_Processor::get_token_type
+	 * @see WP_HTML_Tag_Processor::get_token_name
+	 *
+	 * @since 6.7.0
+	 *
+	 * @access private
+	 *
+	 * @param string $identity Check if the current node has this name or type (depending on what is provided).
+	 * @return bool Whether there is a current element that matches the given identity, whether a token name or type.
+	 */
+	public function current_node_is( string $identity ): bool {
+		$current_node = end( $this->stack );
+		if ( false === $current_node ) {
+			return false;
+		}
+
+		$current_node_name = $current_node->node_name;
+
+		return (
+			$current_node_name === $identity ||
+			( '#doctype' === $identity && 'html' === $current_node_name ) ||
+			( '#tag' === $identity && ctype_upper( $current_node_name ) )
+		);
+	}
+
 	/**
 	 * Returns whether an element is in a specific scope.
 	 *

src/wp-includes/html-api/class-wp-html-processor.php

@@ -1029,7 +1029,7 @@ private function step_in_body() {
 				}
 
 				$this->generate_implied_end_tags();
-				if ( $this->state->stack_of_open_elements->current_node()->node_name !== $token_name ) {
+				if ( ! $this->state->stack_of_open_elements->current_node_is( $token_name ) ) {
 					// @todo Record parse error: this error doesn't impact parsing.
 				}
 				$this->state->stack_of_open_elements->pop_until( $token_name );
@@ -1094,7 +1094,7 @@ private function step_in_body() {
 
 				$this->generate_implied_end_tags();
 
-				if ( $this->state->stack_of_open_elements->current_node()->node_name !== $token_name ) {
+				if ( ! $this->state->stack_of_open_elements->current_node_is( $token_name ) ) {
 					// @todo Record parse error: this error doesn't impact parsing.
 				}
 
@@ -1120,7 +1120,7 @@ private function step_in_body() {
 				if ( $is_li ? 'LI' === $node->node_name : ( 'DD' === $node->node_name || 'DT' === $node->node_name ) ) {
 					$node_name = $is_li ? 'LI' : $node->node_name;
 					$this->generate_implied_end_tags( $node_name );
-					if ( $node_name !== $this->state->stack_of_open_elements->current_node()->node_name ) {
+					if ( ! $this->state->stack_of_open_elements->current_node_is( $node_name ) ) {
 						// @todo Indicate a parse error once it's possible. This error does not impact the logic here.
 					}
 
@@ -1197,7 +1197,7 @@ private function step_in_body() {
 
 				$this->generate_implied_end_tags( $token_name );
 
-				if ( $token_name !== $this->state->stack_of_open_elements->current_node()->node_name ) {
+				if ( ! $this->state->stack_of_open_elements->current_node_is( $token_name ) ) {
 					// @todo Indicate a parse error once it's possible. This error does not impact the logic here.
 				}