perf(jqLite): refactor jqLiteExpandoStore to minimize access to expensive element.ng339 expando property

IgorMinar · IgorMinar · commit 1e8698b33e61 · 2014-08-16T21:50:27.000-07:00
diff --git a/src/jqLite.js b/src/jqLite.js
@@ -318,44 +318,41 @@ function jqLiteRemoveData(element, name) {
   }
 }
 
-function jqLiteExpandoStore(element, key, value) {
+
+function jqLiteExpandoStore(element, createIfNecessary) {
   var expandoId = element.ng339,
       expandoStore = expandoId && jqCache[expandoId];
 
-  if (isDefined(value)) {
-    if (!expandoStore) {
-      element.ng339 = expandoId = jqNextId();
-      expandoStore = jqCache[expandoId] = {};
-    }
-    expandoStore[key] = value;
-  } else {
-    return key ? expandoStore && expandoStore[key] : expandoStore;
+  if (createIfNecessary && !expandoStore) {
+    element.ng339 = expandoId = jqNextId();
+    expandoStore = jqCache[expandoId] = {events: {}, data: {}, handle: undefined};
   }
+
+  return expandoStore;
 }
 
+
 function jqLiteData(element, key, value) {
   if (jqLiteAcceptsData(element)) {
-    var data = jqLiteExpandoStore(element, 'data'),
-        isSetter = isDefined(value),
-        keyDefined = !isSetter && isDefined(key),
-        isSimpleGetter = keyDefined && !isObject(key);
 
-    if (!data && !isSimpleGetter) {
-      jqLiteExpandoStore(element, 'data', data = {});
-    }
+    var isSimpleSetter = isDefined(value);
+    var isSimpleGetter = !isSimpleSetter && key && !isObject(key);
+    var massGetter = !key;
+    var expandoStore = jqLiteExpandoStore(element, !isSimpleGetter);
+    var data = expandoStore && expandoStore.data;
 
-    if (isSetter) {
+    if (isSimpleSetter) { // data('key', value)
       data[key] = value;
     } else {
-      if (keyDefined) {
-        if (isSimpleGetter) {
-          // don't create data in this case.
+      if (massGetter) {  // data()
+        return data;
+      } else {
+        if (isSimpleGetter) { // data('key')
+          // don't force creation of expandoStore if it doesn't exist yet
           return data && data[key];
-        } else {
+        } else { // mass-setter: data({key1: val1, key2: val2})
           extend(data, key);
         }
-      } else {
-        return data;
       }
     }
   }
@@ -727,12 +724,13 @@ forEach({
       return;
     }
 
-    var expandoStore = jqLiteExpandoStore(element);
-    var events = expandoStore && expandoStore.events;
-    var handle = expandoStore && expandoStore.handle;
+    var expandoStore = jqLiteExpandoStore(element, true);
+    var events = expandoStore.events;
+    var handle = expandoStore.handle;
 
-    if (!events) jqLiteExpandoStore(element, 'events', events = {});
-    if (!handle) jqLiteExpandoStore(element, 'handle', handle = createEventHandler(element, events));
+    if (!handle) {
+      handle = expandoStore.handle = createEventHandler(element, events);
+    }
 
     // http://jsperf.com/string-indexof-vs-split
     var types = type.indexOf(' ') ? type.split(' ') : [type];
@@ -896,7 +894,9 @@ forEach({
 
     var dummyEvent, eventFnsCopy, handlerArgs;
     var eventName = event.type || event;
-    var eventFns = (jqLiteExpandoStore(element, 'events') || {})[eventName];
+    var expandoStore = jqLiteExpandoStore(element);
+    var events = expandoStore && expandoStore.events;
+    var eventFns = events && events[eventName];
 
     if (eventFns) {
 
