The Tor Browser / file revision

 function f() {

     var args = arguments, r;

     for (var i = 0; i < args.length; i++)

         r = args[i];

     return r;

 }

 assertEq(f.apply(null, [1, 2, 3, 4, 5, 6]), 6)

 assertEq(f.apply(null, [1, 2, 3, 4, 5]), 5)

 assertEq(f.apply(null, [1, 2, 3, 4]), 4)

 function g(arg) {

     var r;

     for (var i = 0; i < arg.length; i++)

         r = arg[i];

     return r;

 }

 assertEq(g((function () arguments).call(null, 1, 2, 3)), 3);

 assertEq(g(new Float32Array(3)), 0.0);

 assertEq(g([1, 2, 3, 4]), 4);