After looking at the api dump, I've realized that unwrap is actually a verb, and its counter-intuitive to have a verb in property name (https://kotlinlang.org/docs/coding-conventions.html#choose-good-names). So it should be either

1. A function SerialDescriptor.unwrapNullable()
   or
2. A property with a noun, e.g. unwrappedNullable.

I'm not sure what is better. Doing (1) will bring asymmetry with .nullable. (2) is confusing, because it is not clear what 'unwrapped' is since we do not have 'wrapped' anywhere else. Besides, 'unwrappedNullable' sounds like some flavor of a nullable thing, but in reality, returned descriptor may be non-nullable.

You're right, I'm feeling the same. I would prefer unwrappedNullable to not have this asymmetry. I'll commit now. If you feel not comfortable, could we have a third person reviewing this to help chosing a better name ?

@shanshin or @qwwdfsad may help here, I guess

Or, we can do unwrappedOriginal and also unwrap WrappedSerialDescriptor.original (I've looked at all the SerialDescriptors and only SerialDescriptorForNullable and WrappedSerialDescriptor would have sense of unwrapping the original descriptor)

@Chuckame It seems to be that the route of introducing a WrappedSerialDescriptor interface would make a lot of sense, it would also future proof the design to support other wrapping descriptors (and not special case the nullable descriptor only)

I like the idea, but it would mean also renaming the current data class WrappedSerialDescriptor to something else to allow creation of the interface. What do you think @sandwwraith ?

the route of introducing a WrappedSerialDescriptor interface would make a lot of sense, it would also future proof the design to support other wrapping descriptors

IMO this is way out of scope of this PR.

WDYT of nonNullableOriginal name? We can add to the documentation that this property "does not affect descriptors that were created as nullable by directly implementing SerialDescriptor interface."

New doc, is it okay for you @sandwwraith ? I also renamed to nonNullOriginal (pushed)

 * Returns non-nullable serial descriptor for the type, only if this descriptor has been auto-generated (plugin
 * generated descriptors) or with `.nullable` extension on a descriptor or serializer.
 *
 * Otherwise, returns this.
 * 
 * It may return nullable descriptor if this descriptor has been created manually as nullable by directly implementing SerialDescriptor interface.
 *