michael@0: function A() {};
michael@0: A.prototype = [];
michael@0: 
michael@0: function B() {};
michael@0: B.prototype = new A();
michael@0: 
michael@0: function C() {};
michael@0: C.prototype = new B();
michael@0: 
michael@0: function D() {};
michael@0: D.prototype = new C();
michael@0: 
michael@0: function E() {};
michael@0: E.prototype = new D();
michael@0: 
michael@0: function f() {
michael@0:     var o = new B();
michael@0:     for (var i=0; i<10; i++)
michael@0: 	o[i] = i;
michael@0: 
michael@0:     var expected = '{"0":0,"1":1,"2":2,"3":3,"4":4,"5":5,"6":6,"7":7,"8":8,"9":9}';
michael@0:     assertEq(JSON.stringify(o), expected);
michael@0: 
michael@0:     var o = new A();
michael@0:     for (var i=0; i<10; i++)
michael@0: 	o[i] = i;
michael@0: 
michael@0:     assertEq(JSON.stringify(o), expected);
michael@0: 
michael@0:     var o = new D();
michael@0:     for (var i=0; i<10; i++)
michael@0: 	o[i] = i;
michael@0: 
michael@0:     assertEq(JSON.stringify(o), expected);
michael@0: 
michael@0:     var o = new E();
michael@0:     for (var i=0; i<10; i++)
michael@0: 	o[i] = i;
michael@0: 
michael@0:     assertEq(JSON.stringify(o), expected);
michael@0: }
michael@0: f();