Customiser: Prevent JS errors when previewing pages with an <area> …

…tag.

The customiser assumes that `<area>` tags will have a `href` attribute, which isn't necessarily true. Now it checks instead of assuming.

Props janthiel, adamsilverstein.
Fixes #45053.



git-svn-id: https://develop.svn.wordpress.org/trunk@44684 602fd350-edb4-49c9-b593-d223f7449a82

src/js/_enqueues/wp/customize/preview.js

@@ -237,7 +237,7 @@
 	 * @returns {void}
 	 */
 	api.addLinkPreviewing = function addLinkPreviewing() {
-		var linkSelectors = 'a[href], area';
+		var linkSelectors = 'a[href], area[href]';
 
 		// Inject links into initial document.
 		$( document.body ).find( linkSelectors ).each( function() {
@@ -337,6 +337,11 @@
 	api.prepareLinkPreview = function prepareLinkPreview( element ) {
 		var queryParams, $element = $( element );
 
+        // Skip elements with no href attribute. Check first to avoid more expensive checks down the road
+        if ( ! element.hasAttribute( 'href' ) ) {
+            return;
+        }
+
 		// Skip links in admin bar.
 		if ( $element.closest( '#wpadminbar' ).length ) {
 			return;
@@ -776,7 +781,7 @@
 			api.settings.changeset.uuid = uuid;
 
 			// Update UUIDs in links and forms.
-			$( document.body ).find( 'a[href], area' ).each( function() {
+			$( document.body ).find( 'a[href], area[href]' ).each( function() {
 				api.prepareLinkPreview( this );
 			} );
 			$( document.body ).find( 'form' ).each( function() {
@@ -810,7 +815,7 @@
 
 			api.settings.changeset.autosaved = true; // Start deferring to any autosave once changeset is updated.
 
-			$( document.body ).find( 'a[href], area' ).each( function() {
+			$( document.body ).find( 'a[href], area[href]' ).each( function() {
 				api.prepareLinkPreview( this );
 			} );
 			$( document.body ).find( 'form' ).each( function() {