vim-lsp

Async Language Server Protocol plugin for vim8 and neovim.

Installing

Plug 'prabirshrestha/async.vim'
Plug 'prabirshrestha/vim-lsp'

Note: async.vim is required and is used to normalize jobs between vim8 and neovim.

Registering servers

For other languages please refer to the wiki.

if executable('pyls')
    " pip install python-language-server
    au User lsp_setup call lsp#register_server({
        \ 'name': 'pyls',
        \ 'cmd': {server_info->['pyls']},
        \ 'whitelist': ['python'],
        \ })
endif

While most of the time it is ok to just set the name, cmd and whitelist there are times when you need to get more control of the root_uri. By default root_uri for the buffer can be found using lsp#utils#get_default_root_uri() which internaly uses getcwd(). Here is an example that sets the root_uri to the directory where it contains tsconfig.json and traverses up the directories automatically, if it isn't found it returns empty string which tells vim-lsp to start the server but don't initialize the server. If you would like to avoid starting the server you can return empty array for cmd.

if executable('typescript-language-server')
    au User lsp_setup call lsp#register_server({
        \ 'name': 'typescript-language-server',
        \ 'cmd': {server_info->[&shell, &shellcmdflag, 'typescript-language-server --stdio']},
        \ 'root_uri':{server_info->lsp#utils#path_to_uri(lsp#utils#find_nearest_parent_file_directory(lsp#utils#get_buffer_path(), 'tsconfig.json'))},
        \ 'whitelist': ['typescript'],
        \ })
endif

vim-lsp supports incremental changes of Language Server Protocol.

auto-complete

Refer to docs on configuring omnifunc or asyncomplete.vim.

Snippets

vim-lsp does not support snippets by default. If you want snippet integration, you will first have to install a third-party snippet plugin and a plugin that integrates it in vim-lsp. At the moment, you have two options:

1. UltiSnips together with vim-lsp-ultisnips
2. neosnippet.vim together with vim-lsp-neosnippet

For more information, refer to the readme and documentation of the respective plugins.

Semantic highlighting

vim-lsp supports the unofficial extension to the LSP protocol for semantic highlighting (microsoft/vscode-languageserver-node#367). This feature requires Neovim highlights, or Vim with the textprop feature enabled. You will also need to link language server semantic scopes to Vim highlight groups. Refer to :h vim-lsp-semantic for more info.

Folding

You can let the language server automatically handle folding for you. To enable this, you have to set 'foldmethod', 'foldexpr' and (optionally) 'foldtext':

set foldmethod=expr
  \ foldexpr=lsp#ui#vim#folding#foldexpr()
  \ foldtext=lsp#ui#vim#folding#foldtext()

If you would like to disable folding globally, you can add this to your configuration:

let g:lsp_fold_enabled = 0

Also see :h vim-lsp-folding.

Supported commands

Note:

• Some servers may only support partial commands.
• While it is possible to register multiple servers for the same filetype, some commands will pick only the first server that supports it. For example, it doesn't make sense for rename and format commands to be sent to multiple servers.

Command	Description
:LspCodeAction	Gets a list of possible commands that can be applied to a file so it can be fixed (quick fix)
:LspDeclaration	Go to the declaration of the word under the cursor, and open in the current window
:LspDefinition	Go to the definition of the word under the cursor, and open in the current window
:LspDocumentDiagnostics	Get current document diagnostics information
:LspDocumentFormat	Format entire document
:LspDocumentRangeFormat	Format document selection
:LspDocumentSymbol	Show document symbols
:LspHover	Show hover information
:LspImplementation	Show implementation of interface in the current window
:LspNextError	jump to next error
:LspNextReference	jump to next reference to the symbol under cursor
:LspPeekDeclaration	Go to the declaration of the word under the cursor, but open in preview window
:LspPeekDefinition	Go to the definition of the word under the cursor, but open in preview window
:LspPeekImplementation	Go to the implementation of an interface, but open in preview window
:LspPeekTypeDefinition	Go to the type definition of the word under the cursor, but open in preview window
:LspPreviousError	jump to previous error
:LspPreviousReference	jump to previous reference to the symbol under cursor
:LspReferences	Find references
:LspRename	Rename symbol
:LspStatus	Show the status of the language server
:LspTypeDefinition	Go to the type definition of the word under the cursor, and open in the current window
:LspWorkspaceSymbol	Search/Show workspace symbol

Diagnostics

Document diagnostics (e.g. warnings, errors) are enabled by default, but if you preferred to turn them off and use other plugins instead (like Neomake or ALE, set g:lsp_diagnostics_enabled to 0:

let g:lsp_diagnostics_enabled = 0         " disable diagnostics support

Signs

let g:lsp_signs_enabled = 1         " enable signs
let g:lsp_diagnostics_echo_cursor = 1 " enable echo under cursor when in normal mode

Four groups of signs are defined and used: LspError, LspWarning, LspInformation, LspHint. It is possible to set custom text or icon that will be used for each sign (note that icons are only available in GUI). To do this, set some of the following globals: g:lsp_signs_error, g:lsp_signs_warning, g:lsp_signs_information, g:lsp_signs_hint. They should be set to a dict, that contains either text that will be used as sign in terminal, or icon that will be used for GUI, or both. For example:

let g:lsp_signs_error = {'text': '✗'}
let g:lsp_signs_warning = {'text': '‼', 'icon': '/path/to/some/icon'} " icons require GUI
let g:lsp_signs_hint = {'icon': '/path/to/some/other/icon'} " icons require GUI

Also two highlight groups for every sign group are defined (for example for LspError these are LspErrorText and LspErrorLine). By default, LspError text is highlighted using Error group, LspWarning is highlighted as Todo, others use Normal group. Line highlighting is not set by default. If your colorscheme of choise does not provide any of these, it is possible to clear them or link to some other group, like so:

highlight link LspErrorText GruvboxRedSign " requires gruvbox
highlight clear LspWarningLine

Highlights

Highlighting diagnostics requires either NeoVim 0.3+ or Vim with patch 8.1.0579. They are enabled by default when supported, but can be turned off respectively by

let g:lsp_highlights_enabled = 0
let g:lsp_textprop_enabled = 0

Can be customized by setting or linking LspErrorHighlight, LspWarningHighlight, LspInformationHighlight and LspHintHighlight highlight groups.

Virtual text

In NeoVim 0.3 or newer you can use virtual text feature (enabled by default). You can disable it by adding

let g:lsp_virtual_text_enabled = 0

To your configuration.

Virtual text will use the same highlight groups as signs feature.

Highlight references

Highlight references to the symbol under the cursor. To enable, set in your configuration:

let g:lsp_highlight_references_enabled = 1

To change the style of the highlighting, you can set or link the lspReference highlight group, e.g.:

highlight lspReference ctermfg=red guifg=red ctermbg=green guibg=green

Debugging

In order to enable file logging set g:lsp_log_file.

let g:lsp_log_verbose = 1
let g:lsp_log_file = expand('~/vim-lsp.log')

" for asyncomplete.vim log
let g:asyncomplete_log_file = expand('~/asyncomplete.log')