perf(jqLite): optimize event handler

IgorMinar · IgorMinar · commit d05f27e274c4 · 2014-08-18T21:20:09.000-07:00
diff --git a/src/jqLite.js b/src/jqLite.js
@@ -689,11 +689,18 @@ function createEventHandler(element, events) {
       return event.defaultPrevented;
     };
 
+    var eventFns = events[type || event.type];
+    var eventFnsLength = eventFns ? eventFns.length : 0;
+
+    if (!eventFnsLength) return;
+
     // Copy event handlers in case event handlers array is modified during execution.
-    var eventHandlersCopy = shallowCopy(events[type || event.type] || []);
+    if ((eventFnsLength > 1)) {
+      eventFns = shallowCopy(eventFns);
+    }
 
-    for (var i = 0, ii = eventHandlersCopy.length; i < ii; i++) {
-      eventHandlersCopy[i].call(element, event);
+    for (var i = 0; i < eventFnsLength; i++) {
+      eventFns[i].call(element, event);
     }
   };
 
