Incorrect autocomplete with Javascript using nvim-lspconfig

Question

My lspconfig works fine with typescript files, but not with Javascript.

• Autocomplete shows .constructor and other standard props/methods instead of the expected ones defined on the type
• This happens even though the correct type is set (through jsdoc) or inferred from imported typescript modules
• If I simply set the filetype to typescript (:set ft=typescript), it starts working

I used the Array class in the example, but the issue is the same with user-defined types, even when the type definition is written using jsdoc.

How can I make autocomplete work as expected with Javascript files too?

Note: I use native LSP only, other plugins like nvim-cmp and coq-nvim work as expected, but I prefer to avoid them. Since they all use LSP, I suppose I am misconfiguring something.

My relevant configs:

init.vim

" LSP config
set omnifunc=v:lua.vim.lsp.omnifunc
set tagfunc=v:lua.vim.lsp.tagfunc

" open LSP definition
map <F9> :lua vim.lsp.buf.hover()<CR>
inoremap <F9> <C-o>:lua vim.lsp.buf.hover()<CR>

" go to definition
map <F12> :lua vim.lsp.buf.definition()<CR>
inoremap <F12> <C-o>:lua vim.lsp.buf.definition()<CR>

" code completion with omni function
inoremap <C-Space> <C-x><C-o>
inoremap <C-@> <C-x><C-o>

config.lua

-- LSP config
local lspconfig = require('lspconfig')
local servers = { 'bashls', 'sumneko_lua', 'solargraph', 'tsserver', 'vimls' }
for _, lsp in ipairs(servers) do
  lspconfig[lsp].setup({})
end

Full config files:

• https://github.com/paulodiovani/dot-files/blob/1f4166898a839a630e5aa7fd3bbd50fffc855609/home/user/.config/nvim/init.vim#L15-L17
• https://github.com/paulodiovani/dot-files/blob/1f4166898a839a630e5aa7fd3bbd50fffc855609/home/user/.config/nvim/init.vim#L34-L44
• https://github.com/paulodiovani/dot-files/blob/1f4166898a839a630e5aa7fd3bbd50fffc855609/home/user/.config/nvim/lua/config.lua#L54-L59

Output of :LspInfo

 Language client log: /home/diovani/.cache/nvim/lsp.log
 Detected filetype:   javascript
 
 2 client(s) attached to this buffer: 
 
 Client: tsserver (id: 1, pid: 114182, bufnr: [1])
    filetypes:       javascript, javascriptreact, javascript.jsx, typescript, typescriptreact, typescript.tsx
    autostart:       true
    root directory:  /home/diovani/Development/Node/interactive-pbta-bot
    cmd:             typescript-language-server --stdio
 
 Client: null-ls (id: 2, pid: 5001, bufnr: [1])
    filetypes:       typescriptreact, typescript, javascriptreact, javascript, vue, lua, ruby, sh, less, scss, sass, css, yaml, json
    autostart:       false
    root directory:  /home/diovani/Development/Node/interactive-pbta-bot
    cmd:             nvim
 
 Configured servers list: bashls, sumneko_lua, solargraph, tsserver, vimls

Answer 1

I found the solution in this reddit post: https://www.reddit.com/r/neovim/comments/rs47cx/tsserver_and_vimlspomnifunc/.

Neovim comes with its built-in javascript autocomplete which was overriding the omnifunc.

To check if that is happening, open a Javascript file and type:

set omnifunc?

if the result is omnifunc=javascriptcomplete#CompleteJS it is using the built-in autocomplete.

The solution is to set omnifunc (and keymaps, if any) on the attach event of the LSP servers setup, as suggested in lsp_config docs.

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.

Here is my final configuration, finally working:

-- LSP config
local lspconfig = require('lspconfig')
local servers = { 'bashls', 'sumneko_lua', 'solargraph', 'tsserver', 'vimls' }
for _, lsp in ipairs(servers) do
  lspconfig[lsp].setup({
    on_attach = function(_, bufnr)
      vim.api.nvim_buf_set_option(bufnr, 'omnifunc', 'v:lua.vim.lsp.omnifunc')
      vim.api.nvim_buf_set_option(bufnr, 'tagfunc', 'v:lua.vim.lsp.tagfunc')
    end
  })
end