GitHub - nim-lang/langserver: The Nim language server implementation (based on nimsuggest) (original) (raw)
Nim Language Server
Nim Language Server, or nimlangserver, is a language server for Nim.
Installation
IMPORTANT you might want to use latest build of the nimlangserver and/or build it from source.
nimlangserver requires nimble >= 0.16.1
Installing binaries
NB: nimlangserver requires nimsuggest version that supports --v3:
You can install the latest release into $HOME/.nimble/bin using e.g.:
nimble install nimlangserver
From Source
VSCode
- vscode-nim has support for
nimlangserver. Follow the instructions at:https://github.com/nim-lang/vscode-nim#using
Sublime Text
Install LSP-nimlangserver from Package Control.
Zed Editor
Install Nim Extenstion from the Zed Editor extensions.
Helix
Just install the langserver with Nimble and make sure it's on your PATH.
To verify that everything is set up, run:
$ hx --health nim Configured language servers: ✓ nimlangserver: /home/username/.nimble/bin/nimlangserver Configured debug adapter: None Configured formatter: ✓ /home/username/.nimble/bin/nph Tree-sitter parser: ✓ Highlight queries: ✓ Textobject queries: ✓ Indent queries: ✓
Neovim
- lsp Neovim has built-in LSP support. Although, you might want to use something like lsp-config to take care of the boilerplate code for the most LSP configurations. Install
lsp-configusing your favourite plugin manager an place the following code into yourinit.vimconfig:
lua <<EOF
require'lspconfig'.nim_langserver.setup{ settings = { nim = { nimsuggestPath = "~/.nimble/bin/custom_lang_server_build" } } }
EOF
Change configuration to your liking (most probably you don't need to provide any settings at all, defaults should work fine for the majority of the users). You might also want to read lsp-config documentation to setup key bindings, autocompletion and so on.
IMPORTANT you might want to use latest build of the nimlangserver and/or build it from source.
VIM/Neovim
- coc.nvim supports both classical VIM as well as Neovim. It also supports vscode-like
coc-settings.jsonfor LSP configuration. Install the plugin via your favourite plugin manager, createcoc-settings.jsonalongside yourinit.vimand add the following contents to it:
{ "languageserver": { "nim": { "command": "nimlangserver", "filetypes": ["nim"], "trace.server": "verbose", "settings": { "nim": { "nimsuggestPath": "~/.nimble/bin/nimsuggest" } } } } }
Of course, change the configuration to your liking. You might also want to read coc.nvim documentation to setup key bindings, autocompletion and so on.
Configuration Options
nim.projectMapping- configure hownimsuggestshould be started. Here it is sample configuration forVScode. We don't wantnimlangserverto startnimsuggestfor each file and this configuration will allow configuring pairprojectFile/fileRegexso when one of the regexp in the list matches current file thennimlswill userootto startnimsuggest. In case there are no matchesnimlangserverwill try to guess the most suitable project root.
{ "nim.projectMapping": [{ // open files under tests using one nimsuggest instance started with root = test/all.nim "projectFile": "tests/all.nim", "fileRegex": "tests/.*\.nim" }, { // everything else - use main.nim as root. "projectFile": "main.nim", "fileRegex": ".*\.nim" }] }
Note when in a nimble project, nimble will drive the entry points for nimsuggest.
nim.timeout- the request timeout in ms after whichnimlangserverwill restart the language server. If not specified the default is 2 minutes.nim.nimsuggestPath- the path to thenimsuggest. The default is"nimsuggest".nim.autoCheckFile- check the file on the flynim.autoCheckProject- check the project after saving the filenim.autoRestart- auto restart once in case ofnimsuggestcrash. Note that the server won't restart if there weren't any successful calls after the last restart.nim.workingDirectoryMapping- configure the working directory for specific projects.nim.checkOnSave- check the file on save.nim.logNimsuggest- enable logging fornimsuggest.nim.inlayHints- configure inlay hints.nim.notificationVerbosity- configure the verbosity of notifications. Can be set to"none","error","warning", or"info".nim.formatOnSave- format the file on save. Requiresnphto be available in the PATH.nim.nimsuggestIdleTimeout- the timeout in ms after which an idlenimsuggestwill be stopped. If not specified the default is 120 seconds.nim.useNimCheck- usenim checkinstead ofnimsuggestfor linting. Defaults totrue.nim.maxNimsuggestProcesses- the maximum number ofnimsuggestprocesses to keep alive. 0 means unlimited. If not specified the default is 0.
Inlay Hints
Inlay hints are visual snippets displayed by the editor inside your code.
Typical usage for inlay hints is displaying type information but it can go beyond that and provide all sorts of useful context.
nimlangserver offers three kinds of inlay hints:
- Type hints. Show variable types.
- Exception hints. Highlight functions that raise exceptions.
- Parameter hints. Hints for param names in function calls.
- Note: This kind of inlay hints is not implemented yet so enabling it won't do anything at the moment. See issue 183.
Here's how inlay hints look like in VSCode
Here are the same hints in Helix:
In VSCode, inlay hints are enabled by default. You can toggle different kinds of hints in the settings:
- Go to Settings.
- Search inlay.
- Go to Nim configuration.
To enable inlay hints in Neovim, configure lspconfig in your init.vim:
lua << EOF
lspconfig.nim_langserver.setup({ settings = { nim = { inlayHints = { typeHints = true, exceptionHints = true, parameterHints = true, } } },
-- Enable hints on LSP attach on_attach = function(client, bufnr) if client.server_capabilities.inlayHintProvider then vim.lsp.inlay_hint.enable(true, { bufnr = bufnr }) end end })
EOF
In Vim, use the coc configuration to enable inlay hints (see VIM/Neovim).
To enable inlay hints in Helix, add this langserver configuration to your languages.toml (you can toggle different hint kinds individually):
[language-server.nimlangserver.config.nim] inlayHints = { typeHints = true, exceptionHints = true, parameterHints = true }
Features
nimlangserver supports the following LSP features:
- Initialize
- Completions
- Hover
- Goto definition
- Goto declaration
- Goto type definition
- Document symbols
- Find references
- Code actions
- Prepare rename
- Rename symbols
- Inlay hints
- Signature help
- Document formatting (Requires
nphto be available in the PATH.) - Execute command
- Workspace symbols
- Document highlight
- Shutdown
- Exit
You can install nimlangserver using the instructions for your text editor below:
Extension methods
In addition to the standard LSP methods, nimlangserver provides additional nim specific methods.
extension/macroExpand
- Request:
type ExpandTextDocumentPositionParams* = ref object of RootObj textDocument*: TextDocumentIdentifier position*: Position level*: Option[int]
Where:
positionis the position in the document.textDocumentis the document.levelis the how much levels to expand from the current position- Response:
type ExpandResult* = ref object of RootObj range*: Range content*: string
Where:
contentis the expand resultrangeis the original range of the request.
Here it is sample request/response:
[Trace - 11:10:09 AM] Sending request 'extension/macroExpand - (141)'.
Params: {
"textDocument": {
"uri": "file:///.../tests/projects/hw/hw.nim"
},
"position": {
"line": 27,
"character": 2
},
"level": 1
}
[Trace - 11:10:10 AM] Received response 'extension/macroExpand - (141)' in 309ms.
Result: {
"range": {
"start": {
"line": 27,
"character": 0
},
"end": {
"line": 28,
"character": 19
}
},
"content": " block:\n template field1(): untyped =\n a.field1\n\n template field2(): untyped =\n a.field2\n\n field1 = field2"
}
VSCode
Install the vscode-nim extension from here
Emacs
- Install lsp-mode and
nim-modefrom melpa and add the following to your config:
(add-hook 'nim-mode-hook #'lsp)
Transport
nimlangserver supports two transport modes:
- stdio
- socket
To use socket mode, start nimlangserver with the --socket flag. You can set the port using the --port flag. If you don't specify the port, nimlangserver will automatically find an open port and print it in the console.
Test Runner
In order to list and run tests the test library unittest2 >= 0.2.4 must be used. An entry point for the tests must be provided via the vsc extension nim.test.entryPoint or testEntryPoint in future versions of nimble
Related Projects
- nimlsp
Bothnimlangserverandnimlspare based onnimsuggest, but the main difference is thatnimlsphas a single specific version ofnimsuggestembedded in the server executable, whilenimlangserverlaunchesnimsuggestas an external process. This allowsnimlangserverto handle anynimsuggestcrashes more gracefully.
License
MIT




