Fix missing import in SubStates derive macro (#22892)

[Cr0a3]

Objective

Hello, this pr fixes #22892

Solution

I fixed the 'missing import' bug, by hard coding the import in the code generated by the proc macro.

Testing

The code example given in the issue now compiles fine.

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[alice-i-cecile]

CI is complaining about duplicate imports; can you take a look?

[GiantBlargg]

AFAIK you shouldn't put use in macros, as you don't know what may or may not already be included in the namespace.

You probably want something like:

        impl #impl_generics #state_trait_path for #struct_name #ty_generics #where_clause {
            const DEPENDENCY_DEPTH : usize = <<Self as #trait_path>::SourceStates as #state_set_trait_path>::SET_DEPENDENCY_DEPTH + 1;
        }

[Cr0a3]

AFAIK you shouldn't put use in macros, as you don't know what may or may not already be included in the namespace.

You probably want something like:

        impl #impl_generics #state_trait_path for #struct_name #ty_generics #where_clause {
            const DEPENDENCY_DEPTH : usize = <<Self as #trait_path>::SourceStates as #state_set_trait_path>::SET_DEPENDENCY_DEPTH + 1;
        }

Thank you

[Cr0a3]

CI is complaining about duplicate imports; can you take a look?

Sure

[Cr0a3]

CI is complaining about duplicate imports; can you take a look?

I now fixed the issue with the suggestion being helpful 😁

[kfc35]

Confirmed the provided fix works