1 files changed, 35 insertions, 0 deletions
diff --git a/js/src/tests/test262/built-ins/Array/prototype/unshift/clamps-to-integer-limit.js b/js/src/tests/test262/built-ins/Array/prototype/unshift/clamps-to-integer-limit.js
new file mode 100644
index 0000000000..82c3056f5e
--- /dev/null
+++ b/js/src/tests/test262/built-ins/Array/prototype/unshift/clamps-to-integer-limit.js
@@ -0,0 +1,35 @@
+// Copyright (C) 2017 André Bargull. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-array.prototype.unshift
+description: >
+  Length values exceeding 2^53-1 are clamped to 2^53-1.
+info: |
+  1. ...
+  2. Let len be ? ToLength(? Get(O, "length")).
+  3. Let argCount be the number of actual arguments.
+  4. If argCount > 0, then ...
+  5. Perform ? Set(O, "length", len+argCount, true).
+features: [exponentiation]
+---*/
+
+var arrayLike = {};
+
+arrayLike.length = 2 ** 53 - 1;
+Array.prototype.unshift.call(arrayLike);
+assert.sameValue(arrayLike.length, 2 ** 53 - 1, "Length is 2**53 - 1");
+
+arrayLike.length = 2 ** 53;
+Array.prototype.unshift.call(arrayLike);
+assert.sameValue(arrayLike.length, 2 ** 53 - 1, "Length is 2**53");
+
+arrayLike.length = 2 ** 53 + 2;
+Array.prototype.unshift.call(arrayLike);
+assert.sameValue(arrayLike.length, 2 ** 53 - 1, "Length is 2**53 + 2");
+
+arrayLike.length = Infinity;
+Array.prototype.unshift.call(arrayLike);
+assert.sameValue(arrayLike.length, 2 ** 53 - 1, "Length is Infinity");
+
+reportCompare(0, 0);