rust-analyzer reporting file not included in module tree (unlinked-file) if crate directory is inside another crate

[ttencate]

Summary

When a crate is a subdirectory of another crate, rust-analyzer fails to work and gives the error message file not included in module tree (unlinked-file) with a green squiggly line on the first three characters of the file.

I'm filing this as a bug with Helix, rather than with rust-analyzer, because VS Code has no such trouble. If I'm doing something wrong, please let me know.

Reproduction Steps

$ cargo init foo
$ cd foo
$ cargo init bar
$ cd bar
$ helix src/main.rs 

Helix log

~/.cache/helix/helix.log

2023-04-14T15:01:31.620 helix_vcs [ERROR] PeelToCommit(
    Unborn {
        name: FullName(
            "refs/heads/main",
        ),
    },
)
2023-04-14T15:01:31.621 helix_vcs [ERROR] failed to open diff base for /tmp/foo/bar/src/main.rs
2023-04-14T15:01:31.621 helix_vcs [ERROR] PeelToCommit(
    Unborn {
        name: FullName(
            "refs/heads/main",
        ),
    },
)
2023-04-14T15:01:31.621 helix_vcs [ERROR] failed to obtain current head name for /tmp/foo/bar/src/main.rs

Platform

Linux

Terminal Emulator

n/a

Helix Version

23.03

rust-analyzer Version

1.68.2 (9eb3afe 2023-03-27)

[pascalkuthe]

rust analyzer is automatically started at the topmost Cargo.toml file in the workspace. To make the nested crate show up you can either use a cargo workspace (which is usually better) but if you really want separate nested crates then you can create a .helix/config.toml file at the repo root (same directory as .git) and manually configure the additional roots:

[editor]
workspace-lsp-roots = ["bar"]

[ttencate]

I don't think there is a workspace here at all, at least not according to cargo, since there is no [workspace] section anywhere: https://doc.rust-lang.org/cargo/reference/workspaces.html. If I issue cargo build in foo, I don't see bar being built, or vice versa. cargo build -p bar does not work inside foo and vice versa. So it would seem that Helix has a different notion of "workspace root" than cargo does.

[antoyo]

Is there any reason why this doesn't work while opening 2 projects that are at the same level (e.g. not nested) work?
Since the non-nested case works, wouldn't it be easy to make the nested case work?

[the-mikedavis]

When they are not nested we can detect the roots accurately - the topmost Cargo.toml. When they're nested though the higher Cargo.toml is automatically detected as the workspace root for both which is incorrect for the nested project. Using editor.workspace-lsp-roots is the proper way to handle this