System.Globalization.KoreanCalendar.GetDayOfMonth C# (CSharp) Method

        public override int GetDayOfMonth(DateTime time) {
            return (helper.GetDayOfMonth(time));
        }

 public void PosTest3()
 {
     System.Globalization.Calendar kC = new KoreanCalendar();
     DateTime leapDT = new GregorianCalendar().ToDateTime(2003, 1, 29, 0, 0, 0, 0);
     DateTime expectedValue = leapDT;
     DateTime actualValue;
     actualValue = kC.AddMonths(expectedValue, 1);
     Assert.Equal(kC.GetMonth(expectedValue) + 1, kC.GetMonth(actualValue));
     Assert.Equal(kC.GetDayOfMonth(expectedValue) - 1, kC.GetDayOfMonth(actualValue));
 }