function testOwnPropertyWithInOperator() { var o = { 0: 0, 1: 1, 2: 2, 3: 3, 4: 4, 5: 5, 6: 6 }; var a = []; for (var i = 0; i < 7; i++) a.push(i in o); return a.join(","); } assertEq(testOwnPropertyWithInOperator(), "true,true,true,true,true,true,true");