 value).
  _StepTest.min = "14:01";
  _StepTest.max = "15:01";
  this.add_cleanup(function() { _StepTest.min = _StepTest.max = ""; });
  _StepTest.value = "15:00";
  _StepTest.step = "120";
  _StepTest.stepUp();
  assert_in_array(
    _StepTest.value,
    [
      "15:01",
      "15:01:00",
      "15:01:00.0",
      "15:01:00.00",
      "15:01:00.000"],
    "a valid time string representing 1 minute after 3pm");
} , "stop at border on stepUp");
test(function(){
  _StepTest.min = "12:59";
  this.add_cleanup(f