Consider parsing JSON output from check and clippy

[CorvusPrudens]

This issue is motivated by crisidev/bacon-ls#2.

bacon's locations export doesn't surface enough information to fully describe spans in an editor. From my quick investigation, I believe this is because bacon simply parses the direct output of check and clippy, but do correct me if I'm wrong.

However, both tools can provide much more information with their JSON message formats as described here. As far as I can tell, json-diagnostic-rendered-ansi provides the best of both worlds by providing detailed information along with fully rendered messages.

I don't know what the scope of such a change would be, so it's possible this is impractical. However, while it may seem a little roundabout, I've found using bacon in this way very refreshing and more reliable than rust-analyzer for my larger projects. It would be amazing if we could get accurate spans to boot!

[Canop]

it's possible this is impractical

This would require some work but is doable. Biggest problem for me today is finding time.

[crisidev]

I am working on bacon-ls 0.4.0, but when I am done with the release, I have some time to start the MR and try to work on it.

[Canop]

@crisidev I'm working on designing a new version of the analyzer framework, in accordance with this roadmap. Please come chat about what you intend to do exactly before starting a PR.

[crisidev]

Nice, I'll join the chat to see if I can help.

After reading the roadmap, I think I can help updating the analyzers for cargo using json output, to provide precise locations.