diff --git a/test/index.html b/test/index.html
index c76be6215..b49d07047 100644
--- a/test/index.html
+++ b/test/index.html
@@ -47,24 +47,37 @@
 			}());
 
 			function addBizarroMethods() {
+				var funcProto = Function.prototype,
+				    objectProto = Object.prototype,
+				    stringProto = String.prototype;
+
+				var hasOwnProperty = objectProto.hasOwnProperty,
+				    fnToString = funcProto.toString,
+				    nativeString = fnToString.call(objectProto.toString),
+				    propertyIsEnumerable = objectProto.propertyIsEnumerable,
+				    reToString = /toString/g;
+
+				function constant(value) {
+					return function() {
+						return value;
+					};
+				}
+				function createToString(funcName) {
+					return constant(nativeString.replace(reToString, funcName));
+				}
 				// allow bypassing native checks
-				setProperty(Function.prototype, 'toString', (function() {
+				setProperty(funcProto, 'toString', (function() {
 					function wrapper() {
 						setProperty(funcProto, 'toString', fnToString);
 						var result = hasOwnProperty.call(this, 'toString') ? this.toString() : fnToString.call(this);
 						setProperty(funcProto, 'toString', wrapper);
 						return result;
 					}
-					var funcProto = Function.prototype,
-					    fnToString = funcProto.toString,
-					    hasOwnProperty = Object.prototype.hasOwnProperty;
-
-					setProperty(funcProto, '_toString', fnToString);
 					return wrapper;
 				}()));
 
 				// add extensions
-				Function.prototype._method = function() {};
+				funcProto._method = function() {};
 
 				// set bad shims
 				setProperty(Array, '_isArray', Array.isArray);
@@ -85,7 +98,7 @@
 				setProperty(Object, '_keys', Object.keys);
 				setProperty(Object, 'keys', function() {});
 
-				setProperty(Object.prototype, 'hasOwnProperty', (function() {
+				setProperty(objectProto, 'hasOwnProperty', (function() {
 					function wrapper(key) {
 						if (key == '1' && this && typeof this == 'object' && this.length === 2 &&
 								hasOwnProperty.call(this, 'callee') &&
@@ -95,10 +108,6 @@
 						}
 						return hasOwnProperty.call(this, key);
 					}
-					var objectProto = Object.prototype,
-					    hasOwnProperty = objectProto.hasOwnProperty,
-					    propertyIsEnumerable = objectProto.propertyIsEnumerable;
-
 					setProperty(objectProto, '_hasOwnProperty', hasOwnProperty);
 					return wrapper;
 				}()));
@@ -106,8 +115,8 @@
 				setProperty(Number, '_isFinite', Number.isFinite);
 				setProperty(Number, 'isFinite', function() {});
 
-				setProperty(String.prototype, '_contains', String.prototype.contains);
-				setProperty(String.prototype, 'contains', String.prototype._contains ? function() {} : Boolean);
+				setProperty(stringProto, '_contains', stringProto.contains);
+				setProperty(stringProto, 'contains', stringProto._contains ? function() {} : Boolean);
 
 				setProperty(document, '_createDocumentFragment', document.createDocumentFragment);
 				document.createDocumentFragment = function() {};
@@ -129,21 +138,21 @@
 							view.set(new Uint8Array(this));
 							return newBuffer;
 						}
-						function constant(value) {
-							return function() {
-								return value;
-							};
-						}
-						var reToString = /toString/g,
-						    nativeString = Function.prototype.toString.call(toString),
-						    bufferToString = constant(nativeString.replace(reToString, 'ArrayBuffer')),
-						    sliceToString = constant(nativeString.replace(reToString, 'slice'));
-
-						setProperty(ArrayBuffer, 'toString', bufferToString);
-						setProperty(bufferSlice, 'toString', sliceToString);
+						setProperty(ArrayBuffer, 'toString', createToString('ArrayBuffer'));
+						setProperty(bufferSlice, 'toString', createToString('slice'));
 						return ArrayBuffer;
 					}(_ArrayBuffer));
 				}
+				if (!window.Float64Array && window.Uint8Array) {
+					Float64Array = (function() {
+						function Float64Array(buffer, byteOffset, length) {
+							return new Uint8Array(buffer, byteOffset || 0, length || buffer.byteLength);
+						}
+						setProperty(Float64Array, 'BYTES_PER_ELEMENT', 8);
+						setProperty(Float64Array, 'toString', createToString('Float64Array'));
+						return Float64Array;
+					}());
+				}
 				setProperty(window, 'WinRTError', Error);
 
 				setProperty(window, 'exports', window);
@@ -152,6 +161,10 @@
 			}
 
 			function removeBizarroMethods() {
+				var funcProto = Function.prototype,
+				    objectProto = Object.prototype,
+				    stringProto = String.prototype;
+
 				if (Array._isArray) {
 					setProperty(Array, 'isArray', Array._isArray);
 				} else {
@@ -187,13 +200,12 @@
 				} else {
 					delete Number.isFinite;
 				}
-				if (String.prototype._contains) {
-					setProperty(String.prototype, 'contains', String.prototype._contains);
+				if (stringProto._contains) {
+					setProperty(stringProto, 'contains', stringProto._contains);
 				} else {
-					delete String.prototype.contains;
+					delete stringProto.contains;
 				}
-				setProperty(Function.prototype, 'toString', Function.prototype._toString);
-				setProperty(Object.prototype, 'hasOwnProperty', Object.prototype._hasOwnProperty);
+				setProperty(objectProto, 'hasOwnProperty', objectProto._hasOwnProperty);
 
 				document.createDocumentFragment = document._createDocumentFragment;
 				setProperty(document, '_createDocumentFragment', undefined);
@@ -202,7 +214,6 @@
 					ArrayBuffer = _ArrayBuffer;
 				}
 				setProperty(window, '_ArrayBuffer', undefined);
-
 				setProperty(window, 'WinRTError', undefined);
 
 				setProperty(window, 'exports', undefined);
@@ -211,18 +222,13 @@
 
 				delete Array._isArray;
 				delete Date._now;
-				delete Function.prototype._method;
-				delete Function.prototype._toString;
+				delete funcProto._method;
 				delete Object._create;
 				delete Object._defineProperty;
 				delete Object._getPrototypeOf;
 				delete Object._keys;
-				delete Object.prototype._hasOwnProperty;
-				delete String.prototype._contains;
-			}
-
-			if (!window.Float64Array && window.Uint8Array) {
-				Float64Array = Uint8Array;
+				delete objectProto._hasOwnProperty;
+				delete stringProto._contains;
 			}
 			QUnit.config.hidepassed = true;
 
diff --git a/test/test.js b/test/test.js
index fb719196b..242926f8f 100644
--- a/test/test.js
+++ b/test/test.js
@@ -328,6 +328,13 @@
         return;
       }
     }
+    var fnToString = funcProto.toString,
+        nativeString = fnToString.call(toString),
+        reToString = /toString/g;
+
+    function createToString(funcName) {
+      return _.constant(nativeString.replace(reToString, funcName));
+    }
     // load ES6 Set shim
     require('./asset/set');
 
@@ -339,10 +346,9 @@
       _._baseEach = baseEach.baseEach || baseEach['default'] || baseEach;
     }
     // allow bypassing native checks
-    var _fnToString = funcProto.toString;
     setProperty(funcProto, 'toString', function wrapper() {
-      setProperty(funcProto, 'toString', _fnToString);
-      var result = _.has(this, 'toString') ? this.toString() : _fnToString.call(this);
+      setProperty(funcProto, 'toString', fnToString);
+      var result = _.has(this, 'toString') ? this.toString() : fnToString.call(this);
       setProperty(funcProto, 'toString', wrapper);
       return result;
     });
@@ -374,7 +380,7 @@
       if (key == '1' && _.isArguments(this) && _.isEqual(_.values(this), [0, 0])) {
         throw new Error;
       }
-      return _hasOwnProperty.call(this, key);
+      return _.has(this, key);
     });
 
     var _isFinite = Number.isFinite;
@@ -399,18 +405,20 @@
         view.set(new Uint8Array(this));
         return newBuffer;
       }
-      var reToString = /toString/g,
-          nativeString = _fnToString.call(toString),
-          bufferToString = _.constant(nativeString.replace(reToString, 'ArrayBuffer')),
-          sliceToString = _.constant(nativeString.replace(reToString, 'slice'));
-
-      setProperty(ArrayBuffer, 'toString', bufferToString);
-      setProperty(bufferSlice, 'toString', sliceToString);
+      setProperty(ArrayBuffer, 'toString', createToString('ArrayBuffer'));
+      setProperty(bufferSlice, 'toString', createToString('slice'));
       return ArrayBuffer;
     }()));
 
     if (!root.Float64Array) {
-      setProperty(root, 'Float64Array', Uint8Array);
+      setProperty(root, 'Float64Array', (function() {
+        function Float64Array(buffer, byteOffset, length) {
+          return new Uint8Array(buffer, byteOffset || 0, length || buffer.byteLength);
+        }
+        setProperty(Float64Array, 'BYTES_PER_ELEMENT', 8);
+        setProperty(Float64Array, 'toString', createToString('Float64Array'));
+        return Float64Array;
+      }()));
     }
     // fake `WinRTError`
     setProperty(root, 'WinRTError', Error);
@@ -437,7 +445,6 @@
     setProperty(Object, 'keys', _keys);
 
     setProperty(objectProto, 'hasOwnProperty', _hasOwnProperty);
-    setProperty(funcProto,   'toString', _fnToString);
 
     if (_isFinite) {
       setProperty(Number, 'isFinite', _isFinite);