public void it_throws_an_argument_excpetion()
 {
     Assert.Throws <ArgumentException>(() => CronHelpers.RemoveCronYearValue(InvalidCron));
 }
        public void it_returns_the_correct_value()
        {
            var yearlessCron = CronHelpers.RemoveCronYearValue(CronWithYear);

            Assert.AreEqual(CronWithoutYear, yearlessCron);
        }