`@icon` does not work unless `class_name` is specified

[RedMser]

Godot version

4.0.dev (728785d)

System information

Windows 10

Issue description

If you specify only @icon, it does not work. You must add class_name to your script for the icon to show up.

This is unlike the documentation which states:

Add a custom icon to the current script. The icon is displayed in the Scene dock for every node that the script is attached to. For named classes the icon is also displayed in various editor dialogs.

Steps to reproduce

• Create an icon
• Create a node with a script
• Add @icon("res://icon.svg") to the script
• Reload project (since this does not seem to live reload), icon does not show up
• Add class_name Something to the script
• Reload project again, icon now shows up

Minimal reproduction project

icon_annotation.zip

Icon will only show up if you add class_name Something to the script and then reload project.

[RedMser]

Seems like there are some places that explicitly check for ScriptServer::is_global_class and early-returning with no icon (such as EditorData::script_class_get_icon_path).
Might be since the syntax used to be class_name name, "path"?

Possible solutions:

• Update documentation to clarify this limitation, possibly also show an error when the annotation is used without class_name
• Resolve the issue so that @icon works even without class_name

[Gatada]

I actually thought this was by design? Custom classes can have custom icons.

Would be nice to be able to have icons on anything though.

[RedMser]

I actually thought this was by design?

Not sure, since by splitting it to a separate annotation, I'd expect it to be usable standalone. "Silently doing nothing" seems more like a bug than intentional design.

Didn't really investigate how much effort it'd be to make @icon work without class_name, but yeah would be the nicest solution here... :)

[bend-n]

I vote this works without class_name, as custom icons are good for addons, and having duplicate classes of the same name is not something godot appreciates, meaning addons cant have dependencys on other addons.

[akien-mga]

For now the docs should be fixed, as they're wrong. The way this feature implemented is tied to class_name aka "global script classes"

In your project.godot you can see that the two are linked:

_global_script_classes=[{
"base": "Node",
"class": &"MyClass",
"language": &"GDScript",
"path": "res://myclass.gd"
}, {
"base": "Node2D",
"class": &"MyNewClass",
"language": &"GDScript",
"path": "res://node_2d.gd"
}]
_global_script_class_icons={
"MyClass": "",
"MyNewClass": ""
}

To support icons for non global scripts, the scripts would need to be parsed on a case by case basis which might add some technical complexity. Might be possible and maybe not even hard, but it's still in the "new feature" realm, the implementation would need to be rethought.

[YuriSizov]

I think that my intended reading of that documentation snippet was that named classes appear in dialogs -> so the icon is also visible there, not to imply that it should work with unnamed classes. I don't think I've tested that 🙃

To support icons for non global scripts, the scripts would need to be parsed on a case by case basis which might add some technical complexity. Might be possible and maybe not even hard

Yeah, it should be available as a part of the editor filesystem cache.

[bend-n]

I can make a proposal?