lspconfig

A collection of common configurations for Neovim's built-in language server client.

This plugin allows for declaratively configuring, launching, and initializing language servers you have installed on your system. Disclaimer: Language server configurations are provided on a best-effort basis and are community-maintained. See contributions.

lspconfig has extensive help documentation, see :help lspconfig.

LSP overview

Neovim supports the Language Server Protocol (LSP), which means it acts as a client to language servers and includes a Lua framework vim.lsp for building enhanced LSP tools. LSP facilitates features like:

• go-to-definition
• find-references
• hover
• completion
• rename
• format
• refactor

Neovim provides an interface for all of these features, and the language server client is designed to be highly extensible to allow plugins to integrate language server features which are not yet present in Neovim core such as auto-completion (as opposed to manual completion with omnifunc) and snippet integration.

These features are not implemented in this repo, but in Neovim core. See :help lsp for more details.

Install

• Requires Neovim v0.6.1 or Nightly. Update Neovim and 'lspconfig' before reporting an issue.

• Install 'lspconfig' like any other Vim plugin, e.g. with packer.nvim:

  local use = require('packer').use
  require('packer').startup(function()
    use 'wbthomason/packer.nvim' -- Package manager
    use 'neovim/nvim-lspconfig' -- Collection of configurations for the built-in LSP client
  end)

Quickstart

1. Install a language server, e.g. pyright

   npm i -g pyright

2. Add the language server setup to your init.lua.

   require'lspconfig'.pyright.setup{}

3. Launch neovim, the language server will now be attached and providing diagnostics (see :LspInfo)

   nvim main.py
   

4. See Keybindings and completion for mapping useful functions and enabling omnifunc completion

For a full list of servers, see server_configurations.md or :help lspconfig-server-configurations. This document contains installation instructions and additional, optional, customization suggestions for each language server. For some servers that are not on your system path (e.g., jdtls, elixirls), you will be required to manually add cmd as an entry in the table passed to setup. Most language servers can be installed in less than a minute.

Suggested configuration

'lspconfig' does not map keybindings or enable completion by default. The following example configuration provides suggested keymaps for the most commonly used language server functions, and manually triggered completion with omnifunc (<c-x><c-o>).

Note: you must pass the defined on_attach as an argument to every setup {} call and the keybindings in on_attach only take effect on buffers with an active language server.

-- Mappings.
-- See `:help vim.diagnostic.*` for documentation on any of the below functions
local opts = { noremap=true, silent=true }
vim.api.nvim_set_keymap('n', '<space>e', '<cmd>lua vim.diagnostic.open_float()<CR>', opts)
vim.api.nvim_set_keymap('n', '[d', '<cmd>lua vim.diagnostic.goto_prev()<CR>', opts)
vim.api.nvim_set_keymap('n', ']d', '<cmd>lua vim.diagnostic.goto_next()<CR>', opts)
vim.api.nvim_set_keymap('n', '<space>q', '<cmd>lua vim.diagnostic.setloclist()<CR>', opts)

-- Use an on_attach function to only map the following keys
-- after the language server attaches to the current buffer
local on_attach = function(client, bufnr)
  -- Enable completion triggered by <c-x><c-o>
  vim.api.nvim_buf_set_option(bufnr, 'omnifunc', 'v:lua.vim.lsp.omnifunc')

  -- Mappings.
  -- See `:help vim.lsp.*` for documentation on any of the below functions
  vim.api.nvim_buf_set_keymap(bufnr, 'n', 'gD', '<cmd>lua vim.lsp.buf.declaration()<CR>', opts)
  vim.api.nvim_buf_set_keymap(bufnr, 'n', 'gd', '<cmd>lua vim.lsp.buf.definition()<CR>', opts)
  vim.api.nvim_buf_set_keymap(bufnr, 'n', 'K', '<cmd>lua vim.lsp.buf.hover()<CR>', opts)
  vim.api.nvim_buf_set_keymap(bufnr, 'n', 'gi', '<cmd>lua vim.lsp.buf.implementation()<CR>', opts)
  vim.api.nvim_buf_set_keymap(bufnr, 'n', '<C-k>', '<cmd>lua vim.lsp.buf.signature_help()<CR>', opts)
  vim.api.nvim_buf_set_keymap(bufnr, 'n', '<space>wa', '<cmd>lua vim.lsp.buf.add_workspace_folder()<CR>', opts)
  vim.api.nvim_buf_set_keymap(bufnr, 'n', '<space>wr', '<cmd>lua vim.lsp.buf.remove_workspace_folder()<CR>', opts)
  vim.api.nvim_buf_set_keymap(bufnr, 'n', '<space>wl', '<cmd>lua print(vim.inspect(vim.lsp.buf.list_workspace_folders()))<CR>', opts)
  vim.api.nvim_buf_set_keymap(bufnr, 'n', '<space>D', '<cmd>lua vim.lsp.buf.type_definition()<CR>', opts)
  vim.api.nvim_buf_set_keymap(bufnr, 'n', '<space>rn', '<cmd>lua vim.lsp.buf.rename()<CR>', opts)
  vim.api.nvim_buf_set_keymap(bufnr, 'n', '<space>ca', '<cmd>lua vim.lsp.buf.code_action()<CR>', opts)
  vim.api.nvim_buf_set_keymap(bufnr, 'n', 'gr', '<cmd>lua vim.lsp.buf.references()<CR>', opts)
  vim.api.nvim_buf_set_keymap(bufnr, 'n', '<space>f', '<cmd>lua vim.lsp.buf.formatting()<CR>', opts)
end

-- Use a loop to conveniently call 'setup' on multiple servers and
-- map buffer local keybindings when the language server attaches
local servers = { 'pyright', 'rust_analyzer', 'tsserver' }
for _, lsp in pairs(servers) do
  require('lspconfig')[lsp].setup {
    on_attach = on_attach,
    flags = {
      -- This will be the default in neovim 0.7+
      debounce_text_changes = 150,
    }
  }
end

Manual, triggered completion is provided by neovim's built-in omnifunc. For autocompletion, a general purpose autocompletion plugin is required.

Debugging

If you have an issue with 'lspconfig', the first step is to reproduce with a minimal configuration.

The most common reasons a language server does not start or attach are:

1. The language server is not installed. 'lspconfig' does not install language servers for you. You should be able to run the cmd defined in each server's lua module from the command line and see that the language server starts. If the cmd is an executable name instead of an absolute path to the executable, ensure it is on your path.

2. Missing filetype plugins. Certain languages are not detecting by vim/neovim because they have not yet been added to the filetype detection system. Ensure :set ft? shows the filetype and not an empty value.

3. Not triggering root detection. Some language servers will only start if it is opened in a directory, or child directory, containing a file which signals the root of the project. Most of the time, this is a .git folder, but each server defines the root config in the lua file. See server_configurations.md or the source for the list of root directories.

4. You must pass on_attach and capabilities for each setup {} if you want these to take effect.

5. Do not call setup {} twice for the same server. The second call to setup {} will overwrite the first.

Before reporting a bug, check your logs and the output of :LspInfo. Add the following to your init.vim to enable logging:

vim.lsp.set_log_level("debug")

Attempt to run the language server, and open the log with:

:lua vim.cmd('e'..vim.lsp.get_log_path())

Most of the time, the reason for failure is present in the logs.

Built-in commands

• :LspInfo shows the status of active and configured language servers.

The following support tab-completion for all arguments:

• :LspStart <config_name> Start the requested server name. Will only successfully start if the command detects a root directory matching the current config. Pass autostart = false to your .setup{} call for a language server if you would like to launch clients solely with this command. Defaults to all servers matching current buffer filetype.
• :LspStop <client_id> Defaults to stopping all buffer clients.
• :LspRestart <client_id> Defaults to restarting all buffer clients.

The wiki

Please see the wiki for additional topics, including:

• Automatic server installation
• Snippets support
• Project local settings
• Recommended plugins for enhanced language server features

Contributions

If you are missing a language server on the list in server_configurations.md, contributing a new configuration for it would be appreciated. You can follow these steps:

1. Read CONTRIBUTING.md.

2. Create a new file at lua/lspconfig/server_configurations/SERVER_NAME.lua.

   • Copy an existing config to get started. Most configs are simple. For an extensive example see texlab.lua.

3. Ask questions on our Discourse or in the Neovim Matrix room.

You can also help out by testing PRs with the needs-testing label that affect language servers you use regularly.