Make sure `getAttribute` is used without flag when accessing the "type" attribute of an iframe (IE throws error otherwise). [#118 state:resolved] (Zekid, kangax)

CHANGELOG

@@ -1,3 +1,5 @@
+* Make sure `getAttribute` is used without flag when accessing the "type" attribute of an iframe (IE throws error otherwise). [#118 state:resolved] (Zekid, kangax)
+
 * String#gsub should escape RegExp metacharacters when the first argument is a string. [#469 state:resolved] (michael, kangax)
 
 * Fix order of replacement in String#unescapeHTML [#544 state:resolved] (SWeini, kangax)

src/dom/dom.js

@@ -274,20 +274,43 @@ Element.Methods = {
     return id;
   },
   
-  readAttribute: function(element, name) {
-    element = $(element);
-    if (Prototype.Browser.IE) {
-      var t = Element._attributeTranslations.read;
-      if (t.values[name]) return t.values[name](element, name);
-      if (t.names[name]) name = t.names[name];
-      if (name.include(':')) {
-        return (!element.attributes || !element.attributes[name]) ? null : 
-         element.attributes[name].value;
-      }
-    }      
+  readAttribute: (function(){
     
-    return element.getAttribute(name);
-  },
+    var iframeGetAttributeThrowsError = (function(){
+      var el = document.createElement('iframe'),
+          isBuggy = false;
+          
+      document.documentElement.appendChild(el);
+      try {
+        el.getAttribute('type', 2);
+      } catch(e) {
+        isBuggy = true;
+      }
+      document.documentElement.removeChild(el);
+      el = null;
+      return isBuggy;
+    })();
+    
+    return function(element, name) {
+      element = $(element);
+      // check boolean first, to get out of expression faster
+      if (iframeGetAttributeThrowsError &&
+          name === 'type' && 
+          element.tagName.toUpperCase() == 'IFRAME') {
+        return element.getAttribute('type');
+      }
+      if (Prototype.Browser.IE) {
+        var t = Element._attributeTranslations.read;
+        if (t.values[name]) return t.values[name](element, name);
+        if (t.names[name]) name = t.names[name];
+        if (name.include(':')) {
+          return (!element.attributes || !element.attributes[name]) ? null : 
+           element.attributes[name].value;
+        }
+      }      
+      return element.getAttribute(name);
+    }
+  })(),
   
   writeAttribute: function(element, name, value) {
     element = $(element);

test/unit/dom_test.js

@@ -933,6 +933,11 @@ new Test.Unit.Runner({
     var table = $('write_attribute_table');
     this.assertEqual('4', table.readAttribute('cellspacing'));
     this.assertEqual('6', table.readAttribute('cellpadding'));
+    
+    var el = document.createElement('iframe');
+    document.body.appendChild(el);
+    alert(Element.readAttribute(el, 'type'));
+    document.body.removeChild(el);
   },
   
   testElementWriteAttribute: function() {