How can a user run more than one cargo watch command?

[Lokathor]

In cargo watch you can use -x for each thing you want it to do, so you could write

cargo watch -x build -x clippy

And you'd get a build and a clippy run. However, I'm not seeing how to do this in RA.

[kiljacken]

This is not currently supported, and I'm uncertain whether we want to support it given the amount of trouble running a single command from the server already causes :)

[Lokathor]

Okay then can you add a way to run specifically clippy as well as another command?

[matklad]

Note also that long-term, we will remove cargo check execution from rust-analyzer completely, and instead just compute all the diagnostics on the fly, internally. So the long term answer here is that a user needs cargo watch external process anyway.

[Lokathor]

Well rust-analyzer should have some way of running clippy directly in that case.

[matklad]

See

#5383 (comment)

[Lokathor]

Wait you gotta document that somewhere in the readme or something.

Just putting a comment at the end of a closed issue is not helping the users.

[matklad]

Yeah, I might not forget about this next time I get to updating the manual. But this is mostly build-in vscode feature, so I don’t think we necessary must document it ourselves.

[Lokathor]

I read the comment though, and I don't even know what it actually means. Like where do I even put that json block? It's completely unclear.

I think that maybe you're too good at using VS Code, and you've forgotten that most of us actually have no idea how anything with it works ;P

[Michael-F-Bryan]

Like where do I even put that json block? It's completely unclear.

I googled "vs code task" (keywords mentioned in the original comment) and the first result was Integrate with External Tools via Tasks from the official VS Code docs telling me all about how tasks work.

The problem you're always going to have is that rust-analyzer has a lot of features, so even if the relevant information was in the manual it'd be hard to discover because not everyone reads to the end. Plus the line is quite blurry between VS Code and the rust-analyzer plugin, so it's hard to know which project is responsible for documenting a particular feature.

[matklad]

Yeah, my long-term strategy is to crowd-source documentation for all editors. Doesn't work as good as I would like so far, I've bumped the link to the source:

[lnicola]

You can also set cargo clippy as the check command and run cargo watch -x build in a terminal. There used to be some problems with warnings reported only once, but I think they work fine now.

[Lokathor]

The problem is that I want cargo build as my "check" command, and then I can't have clippy for free.

[lnicola]

The problem is that I want cargo build as my "check" command

Why? cargo clippy will report the same warnings, and you can build the code in the background with cargo watch.

[Lokathor]

Well however it happens I don't super care I suppose. The point is that in the GUI for the rust-analyzer settings that you get in VS Code you can only input one command to have rust-analyzer's cargo watch do on repeat, and I want more than one command.

Exactly what those "more than one command" actions are seems unimportant, because various users will have their own needs.

Which is why we need this documentation about how to setup an additional automatic cargo watch, as provided by the PR that referenced this topic (#5407).