The _Init() method doesn't work in C#

[aaronfranke]

Godot version: 3.1.1 and 30e16ff

OS/device including version: Ubuntu 18.04 64-bit

Issue description: It seems that _Init doesn't work at all in C#. @neikeq

Steps to reproduce: Open and run the reproduction project, which contains the following:

public override void _Init()
{
    GD.Print("This text is never printed.");
}

In 3.1.1: The code in _Init() isn't executed at all.

In master: 'TestNode._Init()': no suitable method found to override (CS0115)

Minimal reproduction project: OverrideVoidInit.zip

[Zylann]

What would _init be for in C# since it has constructors?

[neikeq]

Duplicate of #22633

_Init never did anything in C#, and as I recently commented:

I'm removing _Init for now in #29140, but I plan to add a working implementation in the future ...

[NQNStudios]

For API parity, I think _Init() should exist for C#. Or documentation should explain how to replicate the functionality with a C# constructor.