public void ShouldNotValidateWhenArrivalIsLaterThanDeparture() { var invalidViewModel = new ScheduleViewModel { Arrival = new DateTime(2020, 10, 10), Departure = new DateTime(2020, 10, 9) }; var result = validator.IsValid(invalidViewModel); Assert.IsFalse(result); Assert.AreEqual(1, validator.ErrorList.Count()); Assert.AreEqual(ScheduleViewModelMessages.ArrivalLaterThanDeparture, validator.ErrorList.ElementAt(0)); }