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diff --git a/js/src/tests/test262/language/statements/class/subclass/builtin-objects/Map/regular-subclassing.js b/js/src/tests/test262/language/statements/class/subclass/builtin-objects/Map/regular-subclassing.js
new file mode 100644
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+++ b/js/src/tests/test262/language/statements/class/subclass/builtin-objects/Map/regular-subclassing.js
@@ -0,0 +1,28 @@
+// Copyright (C) 2016 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 23.1.1
+description: Subclassing the Map object
+info: |
+  23.1.1 The Map Constructor
+
+  ...
+
+  The Map constructor is designed to be subclassable. It may be used as the
+  value in an extends clause of a class definition. Subclass constructors that
+  intend to inherit the specified Map behaviour must include a super call to the
+  Map constructor to create and initialize the subclass instance with the
+  internal state necessary to support the Map.prototype built-in methods.
+---*/
+
+class M extends Map {}
+
+var map = new M([{ 'foo': 'bar' }]);
+
+assert.sameValue(map.size, 1);
+
+map.set('bar', 'baz');
+
+assert.sameValue(map.size, 2);
+
+reportCompare(0, 0);