From 8c8ffc0a0d7985b33b5b25c4274646729c0de3b6 Mon Sep 17 00:00:00 2001
From: Phred <fearphage@gmail.com>
Date: Tue, 8 Feb 2011 15:58:28 -0800
Subject: [PATCH 1/2] use subclassed array instead of just array methods
 removed caching (didn't work as expected)

---
 classList.js | 81 +++++++++++++++++++++++-----------------------------
 1 file changed, 36 insertions(+), 45 deletions(-)

diff --git a/classList.js b/classList.js
index 9603891..5c2d254 100644
--- a/classList.js
+++ b/classList.js
@@ -1,62 +1,53 @@
-(function () {
+(function (global) {
 
-if (typeof window.DOMTokenList !== 'undefined') return;
+if (typeof global.DOMTokenList !== 'undefined') return;
 
-var indexOf = [].indexOf,
-    slice = [].slice,
-    push = [].push,
-    splice = [].splice,
-    join = [].join;
-
-function DOMTokenList(el) {  
+function DOMTokenList(el) {
   this._element = el;
-  if (el.className != this.classCache) {
-    this._classCache = el.className;
-    
-    var classes = this._classCache.split(' '),
-        i;
-    for (i = 0; i < classes.length; i++) {
-      push.call(this, classes[i]);
-    }
-  }
+  this.push.apply(this, el.className.split(regex));
 };
 
 function setToClassName(el, classes) {
   el.className = classes.join(' ');
 }
 
-DOMTokenList.prototype = {
-  add: function(token) {
-    push.call(this, token);
-    setToClassName(this._element, slice.call(this, 0));
-  },
-  contains: function(token) {
-    return indexOf.call(this, token) !== -1;
-  },
-  item: function(index) {
-    return this[index] || null;
-  },
-  remove: function(token) {
-    var i = indexOf.call(this, token);
-    splice.call(this, i, 1);
-    setToClassName(this._element, slice.call(this, 0));
-  },
-  toString: function() {
-    return join.call(this, ' ');
-  },
-  toggle: function(token) {
-    if (indexOf.call(this, token) === -1) {
-      this.add(token);
-    } else {
-      this.remove(token);
+var
+  key
+  ,regex = /\s+/g
+  ,methods = {
+    add: function(token) {
+      this.push(token);
+      setToClassName(this._element, this);
+    },
+    contains: function(token) {
+      return this.indexOf(token) != -1;
+    },
+    item: function(index) {
+      return this[index] || null;
+    },
+    remove: function(token) {
+      this.splice(this.indexOf(token), 1);
+      setToClassName(this._element, this);
+    },
+    toString: function() {
+      return this.join(' ');
+    },
+    toggle: function(token) {
+      this[this.indexOf(token) == -1 ? 'add' : 'remove'](token);
     }
   }
-};
+;
+
+// IE doesn't maintain the length of subclassed arrays but we don't need it
+DOMTokenList.prototype = new Array;
 
-window.DOMTokenList = DOMTokenList;
+for (key in methods) {
+  DOMTokenList.prototype[key] = methods[key];
+}
+global.DOMTokenList = DOMTokenList;
 
 Element.prototype.__defineGetter__('classList', function () {
   return new DOMTokenList(this);
 });
 
-})();
+})(this);
\ No newline at end of file

From 4777688285031df4bcb52e4b5f21cc310d2e6fc6 Mon Sep 17 00:00:00 2001
From: fearphage <fearphage@gmail.com>
Date: Fri, 18 Feb 2011 14:55:27 -0600
Subject: [PATCH 2/2] moar caching

---
 classList.js | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/classList.js b/classList.js
index 5c2d254..efabaac 100644
--- a/classList.js
+++ b/classList.js
@@ -5,6 +5,10 @@ if (typeof global.DOMTokenList !== 'undefined') return;
 function DOMTokenList(el) {
   this._element = el;
   this.push.apply(this, el.className.split(regex));
+  // cache it if we can
+  if (mutationSupported) {
+    el._tokenList = this;
+  }
 };
 
 function setToClassName(el, classes) {
@@ -36,6 +40,8 @@ var
       this[this.indexOf(token) == -1 ? 'add' : 'remove'](token);
     }
   }
+  ,div = document.createElement('div')
+  ,mutationSupported = false
 ;
 
 // IE doesn't maintain the length of subclassed arrays but we don't need it
@@ -47,7 +53,18 @@ for (key in methods) {
 global.DOMTokenList = DOMTokenList;
 
 Element.prototype.__defineGetter__('classList', function () {
-  return new DOMTokenList(this);
+    return this._tokenList || new DOMTokenList(this);
 });
 
+// detech mutation support
+div.addEventListener('DOMAttrModified'
+  ,function detectMutation() {
+    mutationSupported = true;
+    this.removeEventListener('DOMAttrModified', detectMutation, false);
+  } 
+  ,false
+);
+div.setAttribute('foo', 'bar');
+div = null;
+document.addEventListener('DOMAttrModified', function (e) { delete e.target._tokenList; }, false);
 })(this);
\ No newline at end of file