Multiplayer: Typed Arrays in RPC Functions Throw Errors

[Luzzotica]

Godot version

4.1.1.stable

System information

Godot v4.1.1.stable - macOS 13.4.0 - Vulkan (Mobile) - dedicated AMD Radeon Pro 5500M - Intel(R) Core(TM) i9-9980HK CPU @ 2.40GHz (16 Threads)

Issue description

Here is the RPC function I have created.

rpc("call_local")
func show_items(item_names: Array[String], multiplier: int = 1, reroll: bool = false):
    pass

This function throws the following error on the clients (not the RPC caller).

E 0:00:19:0744   _process_rpc: RPC - 'CanvasLayer(ItemChooserSystem.gd)::show_items': Cannot convert argument 1 from Array to Array
  <C++ Source>   modules/multiplayer/scene_rpc_interface.cpp:294 @ _process_rpc()

I would expect it to be able to convert to the proper type, but getting rid of the type on the array resolves the issue.

Steps to reproduce

1. Create a multiplayer game.
2. Create an RPC function with a typed array
3. Call that RPC function with a valid array
4. See the error on the client

Minimal reproduction project

TypedArrayRPCError.zip

[Jordyfel]

Maybe related to #74391

[dalexeev]

• Duplicate of Unable to do an rpc with a function that uses arguments annotated with an typed Array #69215.
• May be fixed by Core: Add typed array support for binary serialization #78219.

Thanks for reporting the bug nonetheless!