public void When_DecodingToGuid_Invalid_HashId_Should_ThrowException(string valueToDecode)
        {
            // Arrange
            var _sut = new HashingService(AllowedCharacters, Hashstring);

            //Act
            Action testDelegate = () => _sut.DecodeValueToGuid(valueToDecode);

            //Assert
            testDelegate.ShouldThrow <ArgumentException>();
        }
        public void Then_Guid_HashValue_Should_Equal_DecodeValue(string hashValue)
        {
            // Arrange
            var _sut = new HashingService(AllowedCharacters, Hashstring);

            //Act
            Guid expectedValue = Guid.Parse(hashValue);

            var hash        = _sut.HashValue(expectedValue);
            var actualValue = _sut.DecodeValueToGuid(hash);

            //Assert
            expectedValue.Should().Be(actualValue);
        }