public void TargetType()
        {
            // Arrange
            IConverter converter = new DecimalConverter();
            var expectedType = typeof (Decimal);

            // Act
            var actualType = converter.TargetType;

            // Assert
            Assert.Equal(expectedType, actualType);
        }
        public void Conversion()
        {
            // Arrange
            IConverter converter = new DecimalConverter();
            var value = "42,1";
            var expectedValue = (Decimal) 42.1;

            // Act
            using (new LangageSwitcher("fr-fr"))
            {
                var actualValue = converter.Convert(value, converter.TargetType);

                // Assert
                Assert.NotNull(actualValue);
                Assert.IsType<decimal>(actualValue);
                Assert.Equal(expectedValue, (Decimal) actualValue);
            }
        }
        public void BadValueConversion()
        {
            // Arrange
            IConverter converter = new DecimalConverter();
            var value = "Hello";
            var expectedExceptionMessage = Constants.ExceptionMessages.FormatConverterUnableConvert(value, typeof(decimal));
            var expectedInnerExceptionMessage = "Input string was not in a correct format.";

            // Act
            using (new LangageSwitcher("en-us"))
            {
                var actualException = Assert.Throws<CommandLineParserException>(() => converter.Convert(value, converter.TargetType));

                // Assert
                Assert.Equal(expectedExceptionMessage, actualException.Message);
                Assert.NotNull(actualException.InnerException);
                var actualInnerExecption = Assert.IsAssignableFrom<FormatException>(actualException.InnerException);
                Assert.Equal(expectedInnerExceptionMessage, actualInnerExecption.Message);
            }
        }