public void Parse_OutOfRange()
 {
     Assert.Throws <FormatException>(() => FourBitNumber.Parse("200"));
     Assert.Throws <FormatException>(() => FourBitNumber.Parse("16"));
 }
 public void Parse()
 {
     Assert.AreEqual((FourBitNumber)12, FourBitNumber.Parse("12"));
     Assert.AreEqual((FourBitNumber)0, FourBitNumber.Parse("0"));
     Assert.AreEqual((FourBitNumber)15, FourBitNumber.Parse("15"));
 }
 public void Parse_InvalidFormat()
 {
     Assert.Throws <FormatException>(() => FourBitNumber.Parse("sdsd"));
 }