Make Vector<T>::duplicate() const

[aaronfranke]

I tried to duplicate a const PackedStringArray and I noticed that it was impossible, but it should be possible.

[AThousandShips]

Needs an update to the extension API validation

Also, do we need to add a 4.1 one as well now that we have released it, along with 4.0

[akien-mga]

@godotengine/gdextension Does this technically break compat for extensions?

[raulsntos]

If the method's hash changed, then I guess it breaks compat. Otherwise, a GDExtension that was built for 4.1 making use of ClassDB::get_method_with_compatibility passing the old hash will not be able to find the method in 4.2.

To avoid breaking compat, you would need to add a compat method (see #76577).

[dsnopek]

Does this technically break compat for extensions?

Yes, I think @raulsntos is correct.

I guess it's time to start testing out this compatibility system for real?

[aaronfranke]

What is the correct way to add compatibility methods? Is there an example I can follow?

[dsnopek]

Hm, digging into this one deeper, I don't think we currently have a way to provide compatibility methods on Variant types.

gdextension_variant_get_ptr_builtin_method() in gdextension_interface.cpp looks up the method by the name, recalculates its hash, and simply compares that with the value provided. We'll need to add something to variant_call.cpp to store, register and call compatibility methods, similar to the mechanism we already have in ClassDB.

[akien-mga]

"Hash changed" errors shouldn't be silenced. You need to add compat methods for all these, otherwise this breaks binary compatibility.

[dsnopek]

Unfortunately, as I pointed out in my previous comment, there isn't presently a way to register compatibility methods on Variant types. Adding a way to do that is a pre-requisite to this change.