actual = ''; expected = '0,undefined,0,undefined,1,undefined,0,undefined,1,undefined,0,undefined,1,undefined,nocrash,'; // bug 496987 for each(let a in ["", "", true, "", true, "", true]) { appendToActual((function() { for (var e in [0]) { appendToActual( + a) } })()) } appendToActual('nocrash') assertEq(actual, expected)