public void GetDateForYear_ReturnsExpectedValue_WhenDoesntRollToMonday()
        {
            // arrange
            var sut = new FixedHoliday(false, new DateTime(1900, 5, 5));

            // act
            var result = sut.GetDateForYear(2020);

            // assert
            Assert.True(result.present);
            Assert.Equal(new DateTime(2020, 5, 5), result.date);
        }
        public void GetDateForYear_ReturnsExpectedValue_WhenRollsToMonda()
        {
            // arrange
            var sut = new FixedHoliday(true, new DateTime(2019, 3, 22));

            // act
            var result = sut.GetDateForYear(2020);

            // assert
            Assert.True(result.present);
            Assert.Equal(new DateTime(2020, 3, 23), result.date);
        }