Code formatting feature

[poslegm]

There is a great tool for automatic code formatting called scalafmt.

It will be great to be able to call it on current open file with one command like :ScalaFmt.

Similar feature realized in vim-go plugin for go fmt and it works well.

[derekwyatt]

I dunno if you'd want to spawn a JVM every time you wanted to format a file; this is something that is far more appropriate for SBT to do, IMHO. At any rate, I probably won't be writing this one, but if someone has a decent implementation, a PR would be fine.

[poslegm]

Oh, while writing this issue I relied on my experience with a scalafmt-intellij plugin which works very fast. But I missed out that Intellij plugin just call scalafmt functions from already running JVM.

I measured the launch time of scalafmt-cli and it will obviously annoy the user 😒
In this case, I see no reason to keep this issue open.

[ches]

FWIW there may be alternative ways to get this, through language server processes that stay active so are fast to invoke:

• Metals supports scalafmt.
• ENSIME had work in progress on scalafmt before, I'm not sure where it stands now.

[poslegm]

Eventually I achive it in the following way:

1. vim-autoformat plugin with config

let g:formatdef_scalafmt = "'scalafmt --stdin'"
let g:formatters_scala = ['scalafmt']

2. scalafmt built with GraalVM. GraalVM allows instant scalafmt CLI launch:

scalafmt --help  0,01s user 0,02s system 15% cpu 0,199 total

But without GraalVM it is unviable idea.