order stacks of imports and/or pub mod delcarations

[softprops]

I'm looking to apply rustfmt to a couple projects. So far my experience is good except for one surprise when I opt to order my imports it seems like the ordering only applies to a single line of imports, those within brackets. It would be nice to also have this order stacks of use declarations and for bonus points pub mod declarations. It this is not doable let me know. If it easy doable and you can point me in the right direction, also let me know. I'd love to contribute something like this.

[nrc]

I think this is both doable and desirable, however it is not super-easy, but you could certainly have a go. You should look at how we format import items already, specifically look at src/imports.rs and visit_item in src/visitor.rs.

When we walk the AST, we visit one item at a time. In order to format all imports at once, we would need to collect all the import nodes (presumably in a separate pass over the AST) and format them at once. Note that we only want to do this for a given scope, if we were to look at all imports from a walk, we'd get every import in every module. This means we probably need to do a different walk over items in visit_mod (which we don't currently override, see https://dxr.mozilla.org/rust/source/src/libsyntax/visit.rs#61).

If you're keen and have questions once you've looked over that code, feel free to ping me on irc with questions.

[nrc]

Oh, and I would start with just imports and do mod declarations as a followup, they will be similar, but different and will want separate options.

It would be really cool to see this done!

[softprops]

cool. like the fun! label :)

[nrc]

(fun because (I think) it will be the first bit of non-local reformatting)

[jdm]

There may be some prior art that can be stolen from servo/servo#7546 .

[softprops]

going to take a stab at this this weekend. thanks for the links

[cassiersg]

NB: for the mod re-ordering, we need to take exported macros into account...

[cassiersg]

There might be some things to take from Wafflespeanut/rust-sorty.

[softprops]

cool, I started looking at this again last night. look for pr soon