CSharp class is creatable in the scene without passing parameters.

[Shadowblitz16]

Tested versions

v4.4 stable

System information

Debian 13

Issue description

CSharp classes that have the globalclass attribute and no parameter-less constructor are treated as if they have a parameter-less constructor.

using Godot;
using System;

[GlobalClass]
public partial class Test : Godot.Node2D
{
    // This class doesn't have a parameterless constructor but godot is creating it without parameters.
	public Test(Vector2 position)
	{
		Position =position;
	}
}

This fix should probably be done for classes with generics too.

using Godot;
using System;

[GlobalClass]
public partial class Test<T> : Godot.Node2D
{
}

Generics actually error so they are less of a problem.

What should happen in both cases is either...

1. A dialog comes up to pass in parameters and generics.
2. The classes compiles fine and is shown but acts as a abstract class in the node dialog.
3. They are clear compile time errors.

Of course abstract classes should be able to be parameterized and generic since they are never created.

Steps to reproduce

• Download example project.
• Open it.
• Look at script.
• Try to create it in scene.
• It works fine but it's not constructed correctly.

Minimal reproduction project (MRP)

csharp-parameter-bug.zip

[Arctis-Fireblight]

@Shadowblitz16 I believe this is the intended behavior.
IIRC, the C# glue will generate a default constructor even if you dont make one yourself.
Notice how your class is declared as partial. Godot Sharp is generating additional methods and properties for your class at compile time so that it works properly with Godot/Redot.

Anything that inherits from Node has to have a default constructor so that the engine can instantiate it.

The general guidance is that you expose properties for your class to the inspector, and set them that way, and execute whatever Initialization code you need with the Ready() method.

Is there a particular reason you are looking to disallow a default constructor for your class?

[Shadowblitz16]

@Shadowblitz16 I believe this is the intended behavior. IIRC, the C# glue will generate a default constructor even if you dont make one yourself. Notice how your class is declared as partial. Godot Sharp is generating additional methods and properties for your class at compile time so that it works properly with Godot/Redot.

Anything that inherits from Node has to have a default constructor so that the engine can instantiate it.

The general guidance is that you expose properties for your class to the inspector, and set them that way, and execute whatever Initialization code you need with the Ready() method.

Is there a particular reason you are looking to disallow a default constructor for your class?

I need to disallow a default constructors so I can pass in data at construction time.
If this is default behavior can it be changed? generating a default constructors is hacky and could lead to unintended behavior on the game developers end.

[Arctis-Fireblight]

I mean, you can define a private default constructor which would effectively prevent it from being called, but this will likely result in unexpected behavior and crashes.

This may seem kind of backwards from normal C# development, but you really should not be manually calling constructors for anything that inherits from Node. The engine expects to handle creation and destruction of nodes themselves.

Generally speaking, Nodes should be created within engine from the editor and setup via the inspector.
A node's lifecycle typically works as follows:

Node is instantiated in the engine -> C# default constructor is called to setup the C# representation of the Node. -> Any serialized properties of the object are set to whatever they are defined as in the inspector or per their resource file on disk. -> The Ready() method is called to handle any other needed user defined setup. -> The object is now active and can be interacted with, and will be updated every frame until it is destroyed.

There really isnt a way to deviate from this. While this may seem a little counter intuitive from normal C# development, this is how most game engine's work that have C# scripting. The core of the engine itself is written in C++, and all of the real control logic is implemented on the C++ representation of your object, and this will call a hand full of predefined methods on your C# node such as Ready() at the proper times.

[Shadowblitz16]

I assumed csharp godot objects were initialized in the default constructor of the node it is using introp.

That would be nice.

The issue I have with the way it works currently is it's really easy to break.

For example try passing in a node in the constuctor and adding it as a child.

What ideally should happen is the node is initialized in the default constructor of the base node and then children should be pooled to add later when the script is added to the scene.