Emoji: before parsing added nodes test if the text in them contains emoji chars. That speeds up the processing quite a bit.

See #32125.

git-svn-id: https://develop.svn.wordpress.org/trunk@32335 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/js/wp-emoji.js

@@ -70,7 +70,7 @@
 								node = node.parentNode;
 							}
 
-							if ( node && node.nodeType === 1 ) {
+							if ( node && node.nodeType === 1 && test( node.textContent ) ) {
 								parse( node );
 							}
 						}
@@ -84,6 +84,22 @@
 			parse( document.body );
 		}
 
+		/**
+		 * Test if a text string contains emoji characters
+		 *
+		 * @since 4.3.0
+		 *
+		 * @param {String} text The string to test
+		 * @returns Boolean
+		 */
+		function test( text ) {
+			if ( text && twemoji ) {
+				return twemoji.test( text );
+			}
+
+			return false;
+		}
+
 		/**
 		 * Given an element or string, parse any emoji characters into Twemoji images.
 		 *
@@ -144,7 +160,8 @@
 
 		return {
 			replaceEmoji: replaceEmoji,
-			parse: parse
+			parse: parse,
+			test: test
 		};
 	}