top-level `use`s are grouped up onto one line

[cramertj]

I know I've filed issues like this before, but I couldn't find the right one, so I'm opening this one again:

use {
    fidl::endpoints::RequestStream,
    fuchsia_async as fasync,
    fuchsia_zircon as zx,
    std::marker::PhantomData,
};

gets rustfmt'd into

use {
    fidl::endpoints::RequestStream, fuchsia_async as fasync, fuchsia_zircon as zx,
    std::marker::PhantomData,
};

which IMO is pretty clearly less readable.

[scampi]

have you tried the option imports_layout ? The variants HorizontalVertical or Vertical could be what you want.

[cramertj]

No, I haven't, as I can't use unstable options, and any non-default formatting changes have to be approved for use in the project I work on. HorizontalVertical seems like what I would want, though.

In particular, it seems especially wrong to group multiple top-level crates onto the same line.

[mdittmer]

FWIW, I would advocate putting every comma-separable entity on its own line (regardless of nesting) because version control systems can be of more assistance identifying and/or resolving conflicts precisely where they reside. The cost of extra lines is generally low, since most editor/viewer interfaces support folding bracketed lines.

I suspect that even enforcing this at least for top-level crates would go a long way.

[kellytk]

@cramertj

In particular, it seems especially wrong to group multiple top-level crates onto the same line.

While I personally prefer Vertical, #3361 (comment) mentions a possible benefit.

[ytmimi]

This is a duplicate of #3286