reorganize_definitions: Shorten paths that are imported into the current module

[ahomescu]

Add an extra step to reorganize_definitions that checks for every path if it is already imported into the current module, and uses the short import instead of the fully qualified path. E.g.

use crate::foo::Bar;
// Was: fn foo(x: crate::foo::Bar) {}
fn foo(x: Bar) {}

[fw-immunant]

Needs a rebase. Changes in the only commit not on master look good, but I agree with @kkysen that it would be nice to have this in a separate pass.

[ahomescu]

I agree with @kkysen that it would be nice to have this in a separate pass.

I'm not against splitting it, I just have to figure out how to do that. The current implementation uses a lot of internal state from reorganize_definitions.

[kkysen]

@ahomescu, did you see my earlier comment here #1408 (comment)?

[fw-immunant]

While this would be really useful as its own transform, since it appears that would be a substantial effort I'd vote in favor of going ahead and merging as-is this to benefit from it as part of reorganize_definitions in the meantime.

[ahomescu]

@ahomescu, did you see my earlier comment here #1408 (comment)?

Sorry, I missed it until now. Do we still want to try that?

[kkysen]

This doesn't seem to be working in CI. I still see plenty of ::core::ffi::c_uints instead of use ::core::ffi::c_uint;, c_uint.

[ahomescu]

Most recent offline discussion: @kkysen and I agreed that it makes sense to split this off into a separate transform, which would also fix some bugs with scoping and aliases.

[ahomescu]

I moved this to a separate transform.