1 files changed, 21 insertions, 0 deletions
diff --git a/js/src/tests/test262/built-ins/Array/prototype/reduce/15.4.4.21-9-10.js b/js/src/tests/test262/built-ins/Array/prototype/reduce/15.4.4.21-9-10.js
new file mode 100644
index 0000000000..d9b5928953
--- /dev/null
+++ b/js/src/tests/test262/built-ins/Array/prototype/reduce/15.4.4.21-9-10.js
@@ -0,0 +1,21 @@
+// Copyright (c) 2012 Ecma International.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-array.prototype.reduce
+description: >
+    Array.prototype.reduce called with an initial value doesn't
+    consider new elements added to array after it is called
+---*/
+
+function callbackfn(prevVal, curVal, idx, obj) {
+  arr[5] = 6;
+  arr[2] = 3;
+  return prevVal + curVal;
+}
+
+var arr = [1, 2, , 4, '5'];
+
+assert.sameValue(arr.reduce(callbackfn, ""), "12345", 'arr.reduce(callbackfn, "")');
+
+reportCompare(0, 0);