public void ThrowArgumentException_WhenTEnumIsNotEnumeration()
{
// Arrange.
ValidatableArgument<CustomIConvertibleStruct> argument =
new ValidatableArgument<CustomIConvertibleStruct>("argument", default(CustomIConvertibleStruct));
// Act & Assert.
Ensure.ArgumentExceptionIsThrown(
() =>
{
argument.IsMemberOfEnum();
}, "TEnum");
}