diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/proxy/testDirectProxyGet3.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/proxy/testDirectProxyGet3.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,64 @@
+load(libdir + "asserts.js");
+
+/*
+ * Throw a TypeError if the trap reports a different value for a non-writable,
+ * non-configurable property
+ */
+var target = {};
+Object.defineProperty(target, 'foo', {
+    value: 'bar',
+    writable: false,
+    configurable: false
+});
+assertThrowsInstanceOf(function () {
+    new Proxy(target, {
+        get: function (target, name, receiver) {
+            return 'baz';
+        }
+    })['foo'];
+}, TypeError);
+
+/*
+ * Don't throw a TypeError if the trap reports the same value for a non-writable,
+ * non-configurable property
+ */
+assertEq(new Proxy(target, {
+        get: function (target, name, receiver) {
+            return 'bar';
+        }
+    })['foo'],
+    'bar');
+
+
+/*
+ * Don't throw a TypeError if the trap reports a different value for a writable,
+ * non-configurable property
+ */
+Object.defineProperty(target, 'prop', {
+    value: 'bar',
+    writable: true,
+    configurable: false
+});
+assertEq(new Proxy(target, {
+        get: function (target, name, receiver) {
+            return 'baz';
+        }
+    })['prop'],
+    'baz');
+
+
+/*
+ * Don't throw a TypeError if the trap reports a different value for a non-writable,
+ * configurable property
+ */
+Object.defineProperty(target, 'prop2', {
+    value: 'bar',
+    writable: false,
+    configurable: true
+});
+assertEq(new Proxy(target, {
+        get: function (target, name, receiver) {
+            return 'baz';
+        }
+    })['prop2'],
+    'baz');