HTML API: Add support for PRE and LISTING elements.

Adds support for the following HTML elements to the HTML Processor:

 - PRE, LISTING

Previously, these elements were not supported and the HTML Processor would bail when encountering them. Now, with this patch applied, it will proceed to parse an HTML document when encountering those tags.

Developed in #5903

Props jonsurrell, dmsnell
Fixes #60283



git-svn-id: https://develop.svn.wordpress.org/trunk@57317 602fd350-edb4-49c9-b593-d223f7449a82

Author: dmsnell

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

@@ -102,7 +102,7 @@
  *  - Containers: ADDRESS, BLOCKQUOTE, DETAILS, DIALOG, DIV, FOOTER, HEADER, MAIN, MENU, SPAN, SUMMARY.
  *  - Custom elements: All custom elements are supported. :)
  *  - Form elements: BUTTON, DATALIST, FIELDSET, LABEL, LEGEND, METER, PROGRESS, SEARCH.
- *  - Formatting elements: B, BIG, CODE, EM, FONT, I, SMALL, STRIKE, STRONG, TT, U, WBR.
+ *  - Formatting elements: B, BIG, CODE, EM, FONT, I, PRE, SMALL, STRIKE, STRONG, TT, U, WBR.
  *  - Heading elements: H1, H2, H3, H4, H5, H6, HGROUP.
  *  - Links: A.
  *  - Lists: DD, DL, DT, LI, OL, LI.
@@ -112,7 +112,7 @@
  *  - Sectioning elements: ARTICLE, ASIDE, HR, NAV, SECTION.
  *  - Templating elements: SLOT.
  *  - Text decoration: RUBY.
- *  - Deprecated elements: ACRONYM, BLINK, CENTER, DIR, ISINDEX, KEYGEN, MULTICOL, NEXTID, SPACER.
+ *  - Deprecated elements: ACRONYM, BLINK, CENTER, DIR, ISINDEX, KEYGEN, LISTING, MULTICOL, NEXTID, SPACER.
  *
  * ### Supported markup
  *
@@ -684,10 +684,12 @@ private function step_in_body() {
 			case '-FOOTER':
 			case '-HEADER':
 			case '-HGROUP':
+			case '-LISTING':
 			case '-MAIN':
 			case '-MENU':
 			case '-NAV':
 			case '-OL':
+			case '-PRE':
 			case '-SEARCH':
 			case '-SECTION':
 			case '-SUMMARY':
@@ -732,6 +734,18 @@ private function step_in_body() {
 				$this->insert_html_element( $this->state->current_token );
 				return true;
 
+			/*
+			 * > A start tag whose tag name is one of: "pre", "listing"
+			 */
+			case '+PRE':
+			case '+LISTING':
+				if ( $this->state->stack_of_open_elements->has_p_in_button_scope() ) {
+					$this->close_a_p_element();
+				}
+				$this->insert_html_element( $this->state->current_token );
+				$this->state->frameset_ok = false;
+				return true;
+
 			/*
 			 * > An end tag whose tag name is one of: "h1", "h2", "h3", "h4", "h5", "h6"
 			 */
@@ -1007,7 +1021,6 @@ private function step_in_body() {
 			case 'INPUT':
 			case 'LI':
 			case 'LINK':
-			case 'LISTING':
 			case 'MARQUEE':
 			case 'MATH':
 			case 'META':
@@ -1021,7 +1034,6 @@ private function step_in_body() {
 			case 'OPTION':
 			case 'PARAM':
 			case 'PLAINTEXT':
-			case 'PRE':
 			case 'RB':
 			case 'RP':
 			case 'RT':

tests/phpunit/tests/html-api/wpHtmlProcessor.php

@@ -254,7 +254,6 @@ public function data_unsupported_special_in_body_tags() {
 			'IFRAME'    => array( 'IFRAME' ),
 			'INPUT'     => array( 'INPUT' ),
 			'LINK'      => array( 'LINK' ),
-			'LISTING'   => array( 'LISTING' ),
 			'MARQUEE'   => array( 'MARQUEE' ),
 			'MATH'      => array( 'MATH' ),
 			'META'      => array( 'META' ),
@@ -267,7 +266,6 @@ public function data_unsupported_special_in_body_tags() {
 			'OPTION'    => array( 'OPTION' ),
 			'PARAM'     => array( 'PARAM' ),
 			'PLAINTEXT' => array( 'PLAINTEXT' ),
-			'PRE'       => array( 'PRE' ),
 			'RB'        => array( 'RB' ),
 			'RP'        => array( 'RP' ),
 			'RT'        => array( 'RT' ),

tests/phpunit/tests/html-api/wpHtmlProcessorBreadcrumbs.php

@@ -176,7 +176,6 @@ public function data_unsupported_elements() {
 			'IFRAME',
 			'INPUT',
 			'LINK',
-			'LISTING', // Deprecated, use PRE instead.
 			'MARQUEE', // Deprecated.
 			'MATH',
 			'META',
@@ -188,7 +187,6 @@ public function data_unsupported_elements() {
 			'OPTGROUP',
 			'OPTION',
 			'PLAINTEXT', // Neutralized.
-			'PRE',
 			'RB', // Neutralized.
 			'RP',
 			'RT',