private static void ThrowMustDecorateServiceType(Type serviceType,
ConstructorInfo constructor, string paramName)
{
int numberOfServiceTypeDependencies =
DecoratorHelpers.GetNumberOfServiceTypeDependencies(serviceType, constructor);
if (numberOfServiceTypeDependencies == 0)
{
// We must get the real type to be decorated to prevent the exception message from being
// confusing to the user.
// At this point we know that the decorator type implements an service type in some way
// (either open or closed), so we this call will return at least one record.
serviceType = Helpers.GetBaseTypeCandidates(serviceType, constructor.DeclaringType).First();
ThrowMustContainTheServiceTypeAsArgument(serviceType, constructor, paramName);
}
else
{
ThrowMustContainASingleInstanceOfTheServiceTypeAsArgument(serviceType, constructor, paramName);
}
}