Objects whose `_init()` takes arguments fail to be decoded when sent over RPC

[elenakrittik]

Tested versions

4.4dev7

System information

Godot v4.4.dev7 - Windows 10 (build 19045) - Multi-window, 1 monitor - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 3060 (NVIDIA; 32.0.15.6636) - AMD Ryzen 7 5800X 8-Core Processor (8 threads)

Issue description

Let's say you have a PlayerData Object that for convenience defines a constructor:

class_name PlayerData extends Object

var position: Vector3
var rotation: Vector3

func _init(position_: Vector3, rotation_: Vector3) -> void:
    self.position = position_
    self.rotation = rotation_

When you try to send a PlayerData over RPC, the receiving side fails to decode it because it doesn't know what to put into these arguments.

Steps to reproduce

Download the MRP. Open Debug > Customize Run Instances and configure it as shown here:

Run the project. Observe the errors.

Minimal reproduction project (MRP)

netbug.zip

[AThousandShips]

This is always the case, see just like for saving types

[elenakrittik]

Yep, this just needs to be documented

[AThousandShips]

It is, see Object._init

[elenakrittik]

It doesn't mention the networking use case, and if you didn't straight up point me to this, i would've hardly guessed that this is the culprit. Would a PR to add a few words about networking be welcome?

EDIT: I realize now that my "Yep" must've been pretty confusing

[AThousandShips]

I mean it's explicitly said that:

If any other means (such as PackedScene.instantiate or Node.duplicate) are used, the script's initialization will fail.

I would say this counts as "any other case", but we could add it to make it even more obvious