Fix logos_path in generated code

[jannik4]

No description provided.

[jeertmans]

Nice! Could you add a small test that would break if your fix was not present?

[jannik4]

I've already considered it, but unfortunately I don't think it's that easy.
The problem is that you need a crate that has access to logos without having logos directly as a dependency. You can't even shadow logos since the derive macro could (and should) use ::logos.

For example:

• crate logos_reexport depends on logos and reexports logos
• crate logos_use depends only on logos_reexport and uses logos_reexport::logos as logos_path

That should make sure it does not break again, but it adds two new crates to the repository just for this. If that's okay, please tell me where to put them and I can do that.

(Maybe there's something I'm missing, but I think this is the only way.)

[jeertmans]

Hello @jannik4, sorry for the late reply, but I needed to think a bit about this :-)

So I don't think we really need to create a new crate, depending on how cargo actually resolves dependencies.

I have two ideas:

1. Try to create a submodule mod mylogos and re-export logos inside it:

   // any tests/tests/*.rs file, or actually could also be inside some #[cfg(test)]
   mod mylogos {
     pub use logos as logos_path;
   }

   or you can also create a custom module in the tests directory.
2. Because the parent tests directory is actually a crate, you could actually re-export logos in tests/src/lib.rs.

The only doubt I have is whether the tests will fail without your fix, because cargo may be smart enough to see that your re-export points to the same logos as ::logos.

What do you think?

[jannik4]

Isn't this exactly the same as the already existing test tests/tests/crate_.rs? The problem here is that ::logos is always accessible, so if the derive is missing the custom path at one point it continues to just work.

[jeertmans]

Hum ok I guess this isn't as easy as I would have hoped, but not problem I will merge this like this then ;-) Thanks for your work!