def test_add_hours_negative_hours(self):
test_object = WdcTime("1200")
test_object.add_hours(-3)
self.assertEqual(test_object.hours, "09")
def test_add_hours_next_day(self):
test_object = WdcTime("1300")
test_object.add_hours(13)
self.assertEqual(test_object.hours, "02")
def test_add_hours_midnight(self):
test_object = WdcTime("1200")
test_object.add_hours(12)
self.assertEqual(test_object.hours, "00")
def test_add_hours_stays_in_same_day(self):
test_object = WdcTime("0800")
test_object.add_hours(5)
self.assertEqual(test_object.hours, "13")
