When trying to send an Array that is typed with a custom type a type error is emitted and no data is sent.

Tested versions

Reproducible in 4.3.stable

System information

Godot v4.3.stable unknown - Arch Linux #1 SMP PREEMPT_DYNAMIC Thu, 10 Oct 2024 20:11:06 +0000 - Wayland - Vulkan (Forward+) - dedicated AMD Radeon RX 7700S (RADV NAVI33) - AMD Ryzen 7 7840HS w/ Radeon 780M Graphics (16 Threads)

Issue description

I have a multiplayer game it requires clients to send some extra info, like usernames etc. I have a custom class that holds this info. I have created a typed array that hold all connected players. This info needs to be sent to the client instances and so I have an rpc like so :

var players : Array[Player] = []

@rpc("authority")
func send_data(data : Array[Player]):
  players = data

I get the following error when executing this rpc

E 0:00:00:0359   _process_rpc: RPC - 'Node2D(game.gd)::data_rpc': Cannot convert argument 1 from Array to Array
  <C++ Source>   modules/multiplayer/scene_rpc_interface.cpp:290 @ _process_rpc()

when inspecting the node that hold the player array it is empty

Steps to reproduce

Create new project. Setup basic Multiplayer functionality Open a server and a client instance.

func createServer():
  var peer = EnetMultiplayerPeer.new()
  peer.create_server(6643)
  multiplayer.multiplayer_peer = peer

func createClient():
  var peer = EnetMultiplayerPeer.new()
  peer.create_client("127.0.0.1", 6643)
  multiplayer.multiplayer_peer = peer

Create Custom class and create a Typed array that is of that type

class Player:
  var id : int;
  var username : String;

var players : Array[Player] = []

Create rpc function that attempts to sync the array:

@rpc()
func data_rpc(data : Array[Player]):
  players = data

Minimal reproduction project (MRP)

mrp.zip

godotengine / godot