Language Server Protocol (LSP) plugin for Vim. You need Vim version 9.0 or above to use this plugin. This plugin is written using only the Vim9 script.

Installation

You can install this plugin directly from github using the following steps:

mkdir -p $HOME/.vim/pack/downloads/opt
cd $HOME/.vim/pack/downloads/opt
git clone https://github.com/yegappan/lsp
vim -u NONE -c "helptags $HOME/.vim/pack/downloads/opt/lsp/doc" -c q

After installing the plugin using the above steps, add the following line to your $HOME/.vimrc file:

packadd lsp

You can also install and manage this plugin using any one of the Vim plugin managers (dein.vim, pathogen, vam, vim-plug, volt, Vundle, etc.).

You will also need to download and install one or more language servers corresponding to the programming languages that you are using. Refer to the https://langserver.org/ page for the list of available language servers. This plugin doesn't install the language servers.

Features

The following language server protocol (LSP) features are supported:

• Code completion
• Jump to definition, declaration, implementation, type definition
• Peek definition, declaration, implementation, type definition and references
• Display warning and error diagnostics
• Find all symbol references
• Document and Workspace symbol search
• Display code outline
• Rename symbol
• Display type and documentation on hover
• Signature help
• Code action
• Display Call hierarchy
• Display Type hierarchy
• Highlight current symbol references
• Formatting code
• Folding code
• Inlay hints
• Visually select symbol block/region
• Semantic Highlight

Configuration

To use the plugin features with a particular file type(s), you need to first register a LSP server for that file type(s).

The LSP servers are registered using the LspAddServer() function. This function accepts a list of LSP servers.

To register a LSP server, add the following lines to your .vimrc file (use only the LSP servers that you need from the below list). If you used vim-plug to install the LSP plugin, the steps are described later in this section.

" Clangd language server
call LspAddServer([#{
    \    name: 'clangd',
    \    filetype: ['c', 'cpp'],
    \    path: '/usr/local/bin/clangd',
    \    args: ['--background-index']
    \  }])

" Javascript/Typescript language server
call LspAddServer([#{
    \    name: 'typescriptlang',
    \    filetype: ['javascript', 'typescript'],
    \    path: '/usr/local/bin/typescript-language-server',
    \    args: ['--stdio'],
    \  }])

" Go language server
call LspAddServer([#{
    \    name: 'golang',
    \    filetype: ['go', 'gomod'],
    \    path: '/usr/local/bin/gopls',
    \    args: ['serve'],
    \    syncInit: v:true
    \  }])

" Rust language server
call LspAddServer([#{
    \    name: 'rustlang',
    \    filetype: ['rust'],
    \    path: '/usr/local/bin/rust-analyzer',
    \    args: [],
    \    syncInit: v:true
    \  }])

The above lines register the language servers for C/C++, Javascript/Typescript, Go and Rust file types. Refer to the Wiki page for various language server specific configuration.

To register a LSP server, the following information is needed:

The LspAddServer() function accepts a list of LSP servers with the above information.

Some of the LSP plugin features can be enabled or disabled by using the LspOptionsSet() function, detailed in :help lsp-options. Here is an example of configuration with default values:

call LspOptionsSet(#{
        \   aleSupport: v:false,
        \   autoComplete: v:true,
        \   autoHighlight: v:false,
        \   autoHighlightDiags: v:true,
        \   autoPopulateDiags: v:false,
        \   completionMatcher: 'case',
        \   completionMatcherValue: 1,
        \   diagSignErrorText: 'E>',
        \   diagSignHintText: 'H>',
        \   diagSignInfoText: 'I>',
        \   diagSignWarningText: 'W>',
        \   echoSignature: v:false,
        \   hideDisabledCodeActions: v:false,
        \   highlightDiagInline: v:true,
        \   hoverInPreview: v:false,
        \   ignoreMissingServer: v:false,
        \   keepFocusInDiags: v:true,
        \   keepFocusInReferences: v:true,
        \   completionTextEdit: v:true,
        \   diagVirtualTextAlign: 'above',
        \   diagVirtualTextWrap: 'default',
        \   noNewlineInCompletion: v:false,
        \   omniComplete: v:null,
        \   outlineOnRight: v:false,
        \   outlineWinSize: 20,
        \   semanticHighlight: v:true,
        \   showDiagInBalloon: v:true,
        \   showDiagInPopup: v:true,
        \   showDiagOnStatusLine: v:false,
        \   showDiagWithSign: v:true,
        \   showDiagWithVirtualText: v:false,
        \   showInlayHints: v:false,
        \   showSignature: v:true,
        \   snippetSupport: v:false,
        \   ultisnipsSupport: v:false,
        \   useBufferCompletion: v:false,
        \   usePopupInCodeAction: v:false,
        \   useQuickfixForLocations: v:false,
        \   vsnipSupport: v:false,
        \   bufferCompletionTimeout: 100,
        \   customCompletionKinds: v:false,
        \   completionKinds: {},
        \   filterCompletionDuplicates: v:false,
    \ })

If you used vim-plug to install the LSP plugin, then you need to use the LspSetup User autocmd to initialize the LSP server and to set the LSP server options. For example:

let lspOpts = #{autoHighlightDiags: v:true}
autocmd User LspSetup call LspOptionsSet(lspOpts)

let lspServers = [#{
    \     name: 'clang',
    \     filetype: ['c', 'cpp'],
    \     path: '/usr/local/bin/clangd',
    \     args: ['--background-index']
    \ }]
autocmd User LspSetup call LspAddServer(lspServers)

Supported Commands

The following commands are provided to use the LSP features.

Similar Vim LSP Plugins

1. vim-lsp: Async Language Server Protocol
2. Coc: Conquer of Completion
3. vim-lsc: Vim Language Server Client
4. LanguageClient-neovim
5. ALE: Asynchronous Lint Engine
6. Neovim built-in LSP client
7. Omnisharp LSP client