e(typeof(_StepTest.stepUp) ==="function" ) }   , "stepUp function support on input Element");
test(function(){ assert_true(typeof(_StepTest.stepDown) ==="function" ) } , "stepDown function support on input Element");

test(function(){
  _StepTest.value = "12:00";
  _StepTest.step = "";
  _StepTest.stepUp();
  assert_in_array(
    _StepTest.value,
    [
      "12:01",
      "12:01:00",
      "12:01:00.0",
      "12:01:00.00",
      "12:01:00.000"],
    "a valid time string representing 1 minute after noon");