comments IE

Author: jashkenas

underscore.js

@@ -849,7 +849,7 @@
   // Object Functions
   // ----------------
 
-  // keys that won't be iterated by `for key in ...` and thus missed
+  // Keys in IE that won't be iterated by `for key in ...` and thus missed.
   var hasEnumBug = !({toString: null}).propertyIsEnumerable('toString');
   var nonEnumerableProps = ['constructor', 'valueOf', 'isPrototypeOf', 'toString',
                       'propertyIsEnumerable', 'hasOwnProperty', 'toLocaleString'];
@@ -859,9 +859,12 @@
   _.keys = function(obj) {
     if (!_.isObject(obj)) return [];
     if (nativeKeys) return nativeKeys(obj);
-    var keys = [], nonEnumIdx = 7;
+    var keys = [];
     for (var key in obj) if (_.has(obj, key)) keys.push(key);
+    
+    // Ahem, Internet Explorer.
     if (hasEnumBug) {
+      var nonEnumIdx = nonEnumerableProps.length;
       while (nonEnumIdx--) {
         var prop = nonEnumerableProps[nonEnumIdx];
         if (_.has(obj, prop) && !_.contains(keys, prop)) keys.push(prop);