rust-analyzer hangs forever and remembers (?) state

[maxRN]

Have you read the docs and searched existing issues?

• I have read the README's troubleshooting guide and FAQ(https://github.com/mrcjkb/rustaceanvim?tab=readme-ov-file#left_speech_bubble-faq).
• I am using the latest rustaceanvim release.
• I have searched existing issues.
• I have searched existing discussions.
• I have searched the existing issues of other plugins related to this issue (if applicable).
• I have searched the existing rust-analyzer issues (if applicable).
• I can reproduce the issue with stable Neovim (not a distribution or nightly) and the minimal config. Do not open issues here if you are using a distro (like LazyVim) to reproduce.
• This is an issue about rustaceanvim, not rust-analyzer or Neovim.
• This is not an issue with autocompletion.

Neovim version (nvim -v)

v0.11.3

Operating system/version

MacOS 15.5

Output of :checkhealth rustaceanvim

Checking for Lua dependencies ~
- ✅ OK optional dependency nvim-dap not installed. Needed for debugging features [mfussenegger/nvim-dap](https://github.com/mfussenegger/nvim-dap)

Checking external dependencies ~
- ✅ OK rust-analyzer: found rust-analyzer 2025-07-21
- ✅ OK Cargo: found cargo 1.88.0 (873a06493 2025-05-10)
- ✅ OK rustc: found rustc 1.88.0 (6b00bc388 2025-06-23) (built from a source tarball)
- ✅ OK debug adapter: found codelldb 

Checking config ~
- ✅ OK No errors found in config.

Checking for conflicting plugins ~
- ✅ OK No conflicting plugins detected.

Checking for tree-sitter parser ~
- ✅ OK tree-sitter parser for Rust detected.

How to reproduce the issue

I have a project where rust-analyzer hangs forever when opening it, but only when using rustaceanvim. With "normal" lsp-config rust-analyzer it works.
I have reduced the project down to a minimal example, however: If I clone the same example in a new directory it works again.
It seems like there is something about this project wich makes rustaceanvim hang forever and it also somehow remembers it, even though the problematic files should be gone.

I sadly can't share the code, since this is not a public repo.

More information:

• I have fidget.nvim installed so I can see that rust-analyzer "spins" forever and doesn't progress.
• :RustLsp logFile is empty
• I tried it with the nix run minimal flake.
• Using normal rust-analyzer setup it always works.

I have attached the "minimal repro" below, which actually WORKS in my case, but only when cloned into a new directory.

git clone git@github.com:maxRN/rustaceanvim-repro.git
nix run "github:mrcjkb/rustaceanvim#nvim-minimal-stable"
:e src/main.rs
* wait a few seconds for rust-analyzer to finish*
Position cursor on `println!...` press `Shift-K` to get hover information
--> Nothing happens

Expected behaviour

NeoVim should show me hover information for println! macro.

Actual behaviour

NeoVim reports "No information available"

The minimal config used to reproduce this issue.

nix run "github:mrcjkb/rustaceanvim#nvim-minimal-stable"

[maxRN]

Okay it seems to have fixed itself and it might related to this: rust-lang/rust-analyzer#19317
I swear it didn't work at all for multiple days. Sorry for the false report.

[mrcjkb]

[converted this to a Q&A discussion because this is unlikely to be a rustaceanvim bug]

If it works in a fresh clone/checkout, then it's probably caused by local files that aren't under version control (e.g. build artefacts).
If Neovim's file watcher is disabled, rustaceanvim configures rust-analyzer to enable server-side file watching.
You can influence that behaviour by configuring the rust-analyzer.files.watcher setting yourself.

Another thing that can cause rust-analyzer to hang is macros. You can try disabling certain macros in the rust-analyzer settings.