Cache reference to filter in stubbing calls

closes sinonjs#1521

lib/sinon/spy.js

@@ -12,11 +12,14 @@ var wrapMethod = require("./util/core/wrap-method");
 var sinonFormat = require("./util/core/format");
 var valueToString = require("./util/core/value-to-string");
 
+/* cache references to library methods so that they also can be stubbed without problems */
 var push = Array.prototype.push;
 var slice = Array.prototype.slice;
-var callId = 0;
+var filter = Array.prototype.filter;
 var ErrorConstructor = Error.prototype.constructor;
 
+var callId = 0;
+
 function spy(object, property, types) {
     var descriptor, methodDesc;
 
@@ -340,7 +343,7 @@ var spyApi = {
     },
 
     matchingFakes: function (args, strict) {
-        return (this.fakes || []).filter(function (fake) {
+        return filter.call(this.fakes || [], function (fake) {
             return fake.matches(args, strict);
         });
     },

test/issues/issues-test.js

@@ -321,7 +321,7 @@ describe("issues", function () {
         });
     });
 
-    describe("#1512", function () {
+    describe("#1512 - sandbox.stub(obj,protoMethod)", function () {
         var sandbox;
 
         beforeEach(function () {
@@ -341,4 +341,23 @@ describe("issues", function () {
             assert(stub.called);
         });
     });
+
+    describe("#1521 - stubbing Array.prototype.filter", function() {
+        var orgFilter;
+
+        before(function () {
+            orgFilter = Array.prototype.filter;
+        });
+
+        afterEach(function () {
+            Array.prototype.filter = orgFilter;
+        });
+
+        it("should be possible stub filter", function() {
+            var stub = sinon.stub(Array.prototype, "filter");
+            [1,2,3].filter(function() { return false; });
+            assert(stub.calledOnce);
+        });
+
+    });
 });