Make sure (defficient) APPLET, OBJECT and EMBED elements are extended…

… with simulated methods in IE8. Return early if _extendedByPrototype is present on an element.

CHANGELOG

@@ -1,3 +1,5 @@
+* Make sure (defficient) APPLET, OBJECT and EMBED elements are extended with simulated methods in IE8. Return early if _extendedByPrototype is present on an element. (Tobie Langel, kangax)
+
 * Add missing semicolons. This allows to strip newlines from distribution file. (kangax)
 
 * Fix `Template#evaluate` "eating" previous character if `null` was returned from `toTemplateReplacements` function. (Nir, Jürgen Hörmann, kangax)

src/dom/dom.js

@@ -1638,10 +1638,11 @@ Element.extend = (function() {
     // since creating an APPLET element in IE installations without Java triggers warning popup, which we try to avoid
     if (HTMLOBJECTELEMENT_PROTOTYPE_BUGGY) {
       return function(element) {
-        var t;
-        if (element && (t = element.tagName)) {
-          if (/^(?:object|applet|embed)$/i.test(t)) {
+        if (element && typeof element._extendedByPrototype == 'undefined') {
+          var t = element.tagName;
+          if (t && (/^(?:object|applet|embed)$/i.test(t))) {
             extendElementWith(element, Element.Methods);
+            extendElementWith(element, Element.Methods.Simulated);
             extendElementWith(element, Element.Methods.ByTag[t.toUpperCase()]);
           }
         }

test/unit/dom_test.js

@@ -641,10 +641,19 @@ new Test.Unit.Runner({
   },
 
   testElementExtend: function() {
+
+    Element.Methods.Simulated.simulatedMethod = function() { 
+      return 'simulated';
+    };
+    Element.addMethods();
+
     function testTag(tagName) {
       var element = document.createElement(tagName);
       this.assertEqual(element, Element.extend(element));
+      // test method from Methods
       this.assertRespondsTo('show', element);
+      // test method from Simulated
+      this.assertRespondsTo('simulatedMethod', element);
     }
     var element = $('element_extend_test');
     this.assertRespondsTo('show', element);
@@ -669,6 +678,9 @@ new Test.Unit.Runner({
       this.assertEqual(textnode, Element.extend(textnode));
       this.assert(typeof textnode['show'] == 'undefined');
     }, this);
+
+    // clean up
+    delete Element.Methods.Simulated.simulatedMethod;
   },
 
   testElementExtendReextendsDiscardedNodes: function() {