public void No_underlying_reference_type_for_optional_value_type()
        {
            var optionalType = new OptionalType(DataType.Bool);

            var underlyingType = optionalType.UnderlyingReferenceType();

            Assert.Null(underlyingType);
        }
        public void Underlying_reference_type_of_optional_reference_type_is_reference_type()
        {
            var referenceType = new ObjectType("Foo", "Bar", true, ReferenceCapability.Borrowed);
            var optionalType  = new OptionalType(referenceType);

            var underlyingType = optionalType.UnderlyingReferenceType();

            Assert.Same(referenceType, underlyingType);
        }