SyntaxHighlighter cache use seems to not be possible

[Trey2k]

Godot version

4.1.2-stable

godot-cpp version

4.1

System information

Arch linux: 6.3.2-arch1-1

Issue description

The current godot-cpp codegen generates the following definition for _get_line_syntax_highlighting

virtual Dictionary _get_line_syntax_highlighting(int32_t line) const;

In the base engine it is

virtual Dictionary _get_line_syntax_highlighting_impl(int p_line) { return Dictionary(); }

The issue I am running into is I am basing my SyntaxHighlighter implementation on the built in CodeHlighter. It caches color using a HashMap as a private member. But if _get_line_syntax_highlighting is const then we cannot modify the cache as we compute the color.

Steps to reproduce

Generate the header files for the current 4.1 branch

Minimal reproduction project

N/A

[Trey2k]

I have a dirty workaround for this

Dictionary LuaHighlighter::_get_line_syntax_highlighting(int p_line) const {
	return const_cast<LuaHighlighter *>(this)->get_line_syntax_highlighting(p_line);
}

Dictionary LuaHighlighter::get_line_syntax_highlighting(int p_line) {
	...
}

[dsnopek]

Thanks!

I think the fix for this would actually be a change in Godot. It's using the GDVIRTUAL1RC macro in scene/resources/syntax_highlighter.h:

	GDVIRTUAL1RC(Dictionary, _get_line_syntax_highlighting, int)

That would need to be changed to the GDVIRTUAL1R() macro (ie with no C at the end).

That said, changing this would be a source compatibility break: any GDExtensions that currently implement this method would need to update. I think binary compatibility would be fine, though? Given that not probably not a lot of GDExtensions use this, the compatibility breakage may be OK. That would need some wider discussion.