diff -r 7b62478ee76c -r e63b63819133 nashorn/test/script/basic/incheck.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/nashorn/test/script/basic/incheck.js	Fri Dec 21 16:36:24 2012 -0400
@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 2010, 2012, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ * 
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ * 
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ * 
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ * 
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * Check that the expression ("property" in obj) works for own property as 
+ * well as properties 'inherited' from proto chain.
+ * 
+ * @test
+ * @run
+ */
+
+function MyCons() {
+    this.foo = "hello";
+}
+
+MyCons.prototype.func = function() { print("func " + this); }
+MyCons.prototype.num = 1729;
+
+var myObj = new MyCons();
+print("foo? " + ("foo" in myObj));
+print("func? " + ("func" in myObj));
+print("num? " + ("num" in myObj));
+// From Object.prototype
+print("toString?" + ("toString" in myObj));
+
+MyCons.prototype.sun = "a star";
+MyCons.prototype.earth = "a planet";
+
+print("foo? " + ("foo" in myObj));
+print("func? " + ("func" in myObj));
+print("num? " + ("num" in myObj));
+print("sun? " + ("sun" in myObj));
+print("earth? " + ("earth" in myObj));
+print("toString? " + ("toString" in myObj));