https://github.com/crisidev/bacon-ls
A Language Server for Rust using Bacon diagnostics
https://github.com/crisidev/bacon-ls
diagnostics ide lsp lsp-server neovim rust
Last synced: about 1 year ago
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A Language Server for Rust using Bacon diagnostics
- Host: GitHub
- URL: https://github.com/crisidev/bacon-ls
- Owner: crisidev
- License: mit
- Created: 2024-05-17T16:50:59.000Z (about 2 years ago)
- Default Branch: main
- Last Pushed: 2025-03-26T09:54:27.000Z (over 1 year ago)
- Last Synced: 2025-03-28T10:01:44.537Z (about 1 year ago)
- Topics: diagnostics, ide, lsp, lsp-server, neovim, rust
- Language: Rust
- Homepage: https://github.com/crisidev/bacon-ls
- Size: 3.98 MB
- Stars: 81
- Watchers: 2
- Forks: 5
- Open Issues: 3
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# 🐽 Bacon Language Server 🐽
[](https://github.com/crisidev/bacon-ls/actions?query=workflow%3Aci)
[](https://github.com/crisidev/bacon-ls/actions?query=workflow%3Arelease)
[](https://crates.io/crates/bacon-ls)
[](https://crates.io/crates/bacon-ls)
[](https://github.com/crisidev/bacon-ls/blob/main/LICENSE)
[](https://codecov.io/github/crisidev/bacon-ls)
**Are you tired of [rust-analyzer](https://rust-analyzer.github.io/) diagnostics being slow?**
LSP Server wrapper for the exceptional [Bacon](https://dystroy.org/bacon/) exposing [textDocument/diagnostic](https://microsoft.github.io/language-server-protocol/specification#textDocument_diagnostic) and [workspace/diagnostic](https://microsoft.github.io/language-server-protocol/specification#workspace_diagnostic) capabilities.
`bacon-ls` 🐽 does not substitute `rust-analyzer`, it's a companion tool that can help with large
codebases where `rust-analyzer` can become slow dealing with diagnostics.
**`bacon-ls` 🐽 does not help with completion, analysis, refactor, etc... For these, `rust-analyzer` must be running.**
* [Features](#features)
* [Limitations](#limitations)
* [Installation](#installation)
* [VSCode](#vscode)
* [Mason.nvim](#mason.nvim)
* [Manual](#manual)
* [Nix](#nix)
* [Configuration](#configuration)
* [Neovim - LazyVim](#neovim---lazyvim)
* [Neovim - Manual](#neovim---manual)
* [VSCode](#vscode)
* [Coc.nvim](#coc.nvim)
* [Helix](#helix)
* [Troubleshooting](#troubleshooting)
* [Bacon preferences](#bacon-preferences)
* [Vim - Neovim](#vim---neovim)
* [VSCode](#vscode)
* [How does it work?](#how-does-it-work?)
* [Thanks](#thanks)
* [Roadmap to 1.0 - ✅ done 🕖 in progress 🌍 future](#roadmap-to-1.0---✅-done-🕖-in-progress-🌍-future)
See `bacon-ls` 🐽 blog post: https://lmno.lol/crisidev/bacon-language-server
`bacon-ls` 🐽 is meant to be easy to include in your IDE configuration.
## Features
* Read diagnostics from produced by Bacon.
* Push diagnostics to the LSP client on certain events like saving or files changes.
* Precise diagnostics positions.
* Ability to react to changes over document saves and changes that can be configured.
* Replacement code actions as suggested by `clippy`.
* Automatic validation of `bacon` preferences to ensure `bacon-ls` can work with them.
* Start `bacon` in background based on user preferences (requires `bacon` 3.8.0).
* Synchronize diagnostics for all open files.
* Support [cargo workspaces](https://doc.rust-lang.org/book/ch14-03-cargo-workspaces.html).
### Limitations
* Windows support is not tested and probably broken - [#10](https://github.com/crisidev/bacon-ls/issues/10)
## Installation
### VSCode
First, install [Bacon](https://dystroy.org/bacon/#installation).
The VSCode extension is available on both VSCE and OVSX:
* `VSCE` [https://marketplace.visualstudio.com/items?itemName=MatteoBigoi.bacon-ls-vscode](https://marketplace.visualstudio.com/items?itemName=MatteoBigoi.bacon-ls-vscode)
* `OVSX` [https://open-vsx.org/extension/MatteoBigoi/bacon-ls-vscode](https://open-vsx.org/extension/MatteoBigoi/bacon-ls-vscode)
### Mason.nvim
Both Bacon and Bacon-ls are installable via [mason.nvim](https://github.com/williamboman/mason.nvim):
```vim
:MasonInstall bacon bacon-ls
```
### Manual
First, install [Bacon](https://dystroy.org/bacon/#installation) and `bacon-ls` 🐽
```bash
❯❯❯ cargo install --locked bacon bacon-ls
❯❯❯ bacon --version
bacon 3.8.0 # make sure you have at least 3.8.0
❯❯❯ bacon-ls --version
0.14.0 # make sure you have at least 0.14.0
```
### Nix
Both [bacon](https://github.com/Canop/bacon/blob/main/flake.nix) and [bacon-ls](./flake.nix) can be consumed from their Nix flakes.
## Configuration
Configure Bacon export settings with `bacon-ls` 🐽 export format and proper span support in the `bacon` preference file.
To find where the file should be saved, you can use the command `bacon --prefs`:
```toml
[jobs.bacon-ls]
command = [ "cargo", "clippy", "--workspace", "--tests", "--all-targets", "--all-features", "--message-format", "json-diagnostic-rendered-ansi" ]
analyzer = "cargo_json"
need_stdout = true
[exports.cargo-json-spans]
auto = true
exporter = "analyzer"
line_format = "{diagnostic.level}|:|{span.file_name}|:|{span.line_start}|:|{span.line_end}|:|{span.column_start}|:|{span.column_end}|:|{diagnostic.message}|:|{diagnostic.rendered}|:|{span.suggested_replacement}"
path = ".bacon-locations"
```
**NOTE: `bacon` MUST be running to generate the export locations with the `bacon-ls` job: `bacon -j bacon-ls`.
From `bacon-ls` 0.10.0, this is done automatically if the option `runBaconInBackground` is set to true.**
The language server can be configured using the appropriate LSP protocol and
supports the following values:
- `locationsFile` Bacon export filename (default: `.bacon-locations`).
- `updateOnSave` Try to update diagnostics every time the file is saved (default: true).
- `updateOnSaveWaitMillis` How many milliseconds to wait before updating diagnostics after a save (default: 1000).
- `validateBaconPreferences`: Try to validate that `bacon` preferences are setup correctly to work with `bacon-ls` (default: true).
- `createBaconPreferencesFile`: If no `bacon` preferences file is found, create a new preferences file with the `bacon-ls` job definition (default: true).
- `runBaconInBackground`: Run `bacon` in background for the `bacon-ls` job (default: true)
- `runBaconInBackgroundCommandArguments`: Command line arguments to pass to `bacon` running in background (default "--headless -j bacon-ls")
- `synchronizeAllOpenFilesWaitMillis`: How many milliseconds to wait between background diagnostics check to synchronize all open files (default: 2000).
### Neovim - LazyVim
```lua
vim.g.lazyvim_rust_diagnostics = "bacon-ls"
```
### Neovim - Manual
NeoVim requires [nvim-lspconfig](https://github.com/neovim/nvim-lspconfig/) to be configured
and [rust-analyzer](https://rust-analyzer.github.io/) diagnostics must be turned off for `bacon-ls` 🐽
to properly function.
`bacon-ls` is part of `nvim-lspconfig` from commit
[6d2ae9f](https://github.com/neovim/nvim-lspconfig/commit/6d2ae9fdc3111a6e8fd5db2467aca11737195a30)
and it can be configured like any other LSP server works best when
[vim.diagnostics.opts.update_in_insert](https://neovim.io/doc/user/diagnostic.html#vim.diagnostic.Opts)
is set to `true`.
```lua
require("lspconfig").bacon_ls.setup({
init_options = {
updateOnSave = true
updateOnSaveWaitMillis = 1000
...
}
})
```
For `rust-analyzer`, these 2 options must be turned off:
```lua
rust-analyzer.checkOnSave.enable = false
rust-analyzer.diagnostics.enable = false
```
### VSCode
The extension can be configured using the VSCode settings interface.
**It is very important that rust-analyzer `Check On Save` and `Diagnostics` are turned off for `bacon-ls` to work properly:**
* Untick `Rust-analyzer -> general -> Check On Save`
* Untick `Rust-analyzer -> diagnostics -> Enable`
### Coc.nvim
```vim
call coc#config('languageserver', {
\ 'bacon-ls': {
\ 'command': '~/.cargo/bin/bacon-ls',
\ 'filetypes': ['rust'],
\ 'rootPatterns': ['.git/', 'Cargo.lock', 'Cargo.toml'],
\ 'initializationOptions': {
\ 'updateOnSave': v:true,
\ 'updateOnSaveWaitMillis': 1000,
\ },
\ 'settings': {}
\ }
\ })
```
### Helix
Extend your `languages.toml` with the following:
```toml
[[language]]
name = "rust"
language-servers = ["rust-analyzer", "bacon-ls"]
[language-server.rust-analyzer.config]
checkOnSave = { enable = false }
diagnostics = { enable = false }
[language-server.bacon-ls]
command = "bacon-ls"
```
## Troubleshooting
`bacon-ls` 🐽 can produce a log file in the folder where its running by exporting the `RUST_LOG` variable in the shell:
### Bacon preferences
If the `bacon` preference are not correct, an error message will be published to the LSP client, advising the user to
check the README.
### Vim - Neovim
```bash
❯❯❯ export RUST_LOG=debug
❯❯❯ nvim src/some-file.rs # or vim src/some-file.rs
# the variable can also be exported for the current command and not for the whole shell
❯❯❯ RUST_LOG=debug nvim src/some-file.rs # or RUST_LOG=debug vim src/some-file.rs
❯❯❯ tail -F ./bacon-ls.log
```
### VSCode
Enable debug logging in the extension options.
```bash
❯❯❯ tail -F ./bacon-ls.log
```
## How does it work?
`bacon-ls` 🐽 reads the diagnostics location list generated
by [Bacon's export-locations](https://dystroy.org/bacon/config/#export-locations)
and exposes them on STDIO over the LSP protocol to be consumed
by the client diagnostics.
It requires [Bacon](https://dystroy.org/bacon/) to be running alongside
to ensure regular updates of the export locations.
The LSP client reads them as response to `textDocument/diagnostic` and `workspace/diagnostic`.
## Thanks
`bacon-ls` 🐽 has been inspired by [typos-lsp](https://github.com/tekumara/typos-lsp).
## Roadmap to 1.0 - ✅ done 🕖 in progress 🌍 future
- ✅ Implement LSP server interface for `textDocument/diagnostic` and `workspace/diagnostic`
- ✅ Manual Neovim configuration
- ✅ Manual [LazyVim](https://www.lazyvim.org) configuration
- ✅ Automatic NeoVim configuration
- ✅ Add `bacon-ls` to [nvim-lspconfig](https://github.com/neovim/nvim-lspconfig/) - https://github.com/neovim/nvim-lspconfig/pull/3160
- ✅ Add `bacon` and `bacon-ls` to [mason.nvim](https://github.com/williamboman/mason.nvim) - https://github.com/mason-org/mason-registry/pull/5774
- ✅ Add `bacon-ls` to LazyVim [Rust extras](https://github.com/LazyVim/LazyVim/blob/main/lua/lazyvim/plugins/extras/lang/rust.lua) - https://github.com/LazyVim/LazyVim/pull/3212
- ✅ Add compiler hints to [Bacon](https://dystroy.org/bacon/) export locations - https://github.com/Canop/bacon/pull/187 https://github.com/Canop/bacon/pull/188
- ✅ Support correct span in [Bacon](https://dystroy.org/bacon/) export locations - working from `bacon` 3.7 and `bacon-ls` 0.6.0
- ✅ VSCode extension and configuration - available on the [release](https://github.com/crisidev/bacon-ls/releases) page from 0.6.0
- ✅ VSCode extension published available on Marketplace
- ✅ Add `bacon-ls` to `bacon` website - https://github.com/Canop/bacon/pull/289
- ✅ Smarter handling of parsing the Bacon locations file
- ✅ Faster response after a save event
- ✅ Replacement code actions
- ✅ Validate `bacon` preferences and return an error to the LSP client if they are not compatible with `bacon` - working from `bacon-ls` 0.9.0
- ✅ Create `bacon` preferences file if not found on disk - working from `bacon-ls` 0.10.0
- ✅ Start `bacon` in background based on user preferences - working from `bacon-ls` 0.10.0
- ✅ Synchronize diagnostics for all open files - working from `bacon-ls` 0.10.0
- ✅ Support Helix editor - working from `bacon-ls` 0.12.0
- ✅ Nix flake support
- ✅ Support [cargo workspaces](https://doc.rust-lang.org/book/ch14-03-cargo-workspaces.html) - working from `bacon-ls` 0.14.0
- 🌍 Emacs configuration