public void CurrentStartOfQuarterShouldReturnExpectedResult()
        {
            using ( ShimsContext.Create() )
            {
                ShimDateTime.TodayGet = () => new DateTime( 2013, 6, 1 );

                var expected = new DateTime( 2013, 4, 1 );
                var target = new GregorianCalendar();
                var actual = target.CurrentStartOfQuarter();

                Assert.Equal( expected, actual );
            }
        }