Diagnostic attributes for traits behind #[cgp_component]

[iMashtak]

Would errors of CGP DSL be more informative when writing #[diagnostic::on_unimplemented()] for #[cgp_component] traits and propagate whem further for generated traits? Now for that kind of code:

#[diagnostic::on_unimplemented(
    message = "message",
    label = "label"
)]
#[cgp_component(SelectClauseBuilder)]
pub trait CanBuildSelectClause<Code> {
    fn build_select(&self, code: PhantomData<Code>) -> String;
}

I have the following warning:

`#[diagnostic::on_unimplemented]` can only be applied to trait definitions

Or am I wrong and that diagnostics will not help even if properly applied?