public void GetLastSundayInMonth_GivenTheYear2018_ShouldReturnLastSundayOfMonth6()
        {
            //---------------Arrange-------------------
            LastSunday last     = CreateLastSunday();
            var        expected = "2018-06-24";
            //---------------Act----------------------
            var actual = last.GetLastSundayInMonth(2018);

            //---------------Assert----------------------
            Assert.AreEqual(actual.ElementAt(5), expected);
        }
        public void GetLastSundayInMonth_GivenTheYear2013_ShouldReturnLastSundayOfMonth12()
        {
            //---------------Arrange-------------------
            LastSunday last     = CreateLastSunday();
            var        expected = "2013-12-29";
            //---------------Act----------------------
            var actual = last.GetLastSundayInMonth(2013);

            //---------------Assert----------------------
            Assert.AreEqual(actual.Last(), expected);
        }