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diff --git a/js/src/tests/test262/built-ins/TypedArray/prototype/reduce/get-length-uses-internal-arraylength.js b/js/src/tests/test262/built-ins/TypedArray/prototype/reduce/get-length-uses-internal-arraylength.js
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+++ b/js/src/tests/test262/built-ins/TypedArray/prototype/reduce/get-length-uses-internal-arraylength.js
@@ -0,0 +1,48 @@
+// Copyright (C) 2016 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-%typedarray%.prototype.reduce
+description: Get "length" uses internal ArrayLength
+info: |
+  22.2.3.20 %TypedArray%.prototype.reduce ( callbackfn [ , initialValue ] )
+
+  %TypedArray%.prototype.reduce is a distinct function that implements the same
+  algorithm as Array.prototype.reduce as defined in 22.1.3.19 except that the
+  this object's [[ArrayLength]] internal slot is accessed in place of performing
+  a [[Get]] of "length".
+
+  22.1.3.19 Array.prototype.reduce ( callbackfn [ , initialValue ] )
+
+  1. Let O be ? ToObject(this value).
+  2. Let len be ? ToLength(? Get(O, "length")).
+  ...
+includes: [testTypedArray.js]
+features: [TypedArray]
+---*/
+
+var getCalls = 0;
+var desc = {
+  get: function getLen() {
+    getCalls++;
+    return 0;
+  }
+};
+
+Object.defineProperty(TypedArray.prototype, "length", desc);
+
+testWithTypedArrayConstructors(function(TA) {
+  var sample = new TA([42, 43]);
+  var calls = 0;
+
+  Object.defineProperty(TA.prototype, "length", desc);
+  Object.defineProperty(sample, "length", desc);
+
+  sample.reduce(function() {
+    calls++;
+  }, 0);
+
+  assert.sameValue(getCalls, 0, "ignores length properties");
+  assert.sameValue(calls, 2, "iterations are not affected by custom length");
+});
+
+reportCompare(0, 0);