LanguageClient neovim

See Getting started to build the ccls executable
Install LanguageClient-neovim You may use the plugin manager vim-plug

LanguageClient-neovim

nvim +PlugInstall +UpdateRemotePlugins +qa

~/.config/nvim/settings.json (optional, by default it creates cache directory .ccls-cache in the project root)

{
        "initializationOptions": {
                "cacheDirectory": "/tmp/ccls"
        }
}

~/.config/nvim/init.vim

let g:LanguageClient_serverCommands = {
    \ 'cpp': ['ccls', '--log-file=/tmp/cc.log'],
    \ 'c': ['ccls', '--log-file=/tmp/cc.log'],
    \ }

let g:LanguageClient_loadSettings = 1 " Use an absolute configuration path if you want system-wide settings
let g:LanguageClient_settingsPath = '/home/YOUR_USERNAME/.config/nvim/settings.json'

Make sure you have .ccls or compile_commands.json in your project root. Open a file in the project, run :LanguageClientStart.

These features will work out-of-the-box.

nn <silent> <M-j> :call LanguageClient#textDocument_definition()<cr>
nn <silent> <C-,> :call LanguageClient#textDocument_references({'includeDeclaration': v:false})<cr>
nn <silent> K :call LanguageClient#textDocument_hover()<cr>

`textDocument/documentHighlight`

augroup LanguageClient_config
  au!
  au BufEnter * let b:Plugin_LanguageClient_started = 0
  au User LanguageClientStarted setl signcolumn=yes
  au User LanguageClientStarted let b:Plugin_LanguageClient_started = 1
  au User LanguageClientStopped setl signcolumn=auto
  au User LanguageClientStopped let b:Plugin_LanguageClient_stopped = 0
  au CursorMoved * if b:Plugin_LanguageClient_started | sil call LanguageClient#textDocument_documentHighlight() | endif
augroup END

`$ccls/navigate`

Semantic navigation. Roughly,

"D" => first child declaration "L" => previous declaration "R" => next declaration "U" => parent declaration

nn <silent> xh :call LanguageClient#findLocations({'method':'$ccls/navigate','direction':'L'})<cr>
nn <silent> xj :call LanguageClient#findLocations({'method':'$ccls/navigate','direction':'D'})<cr>
nn <silent> xk :call LanguageClient#findLocations({'method':'$ccls/navigate','direction':'U'})<cr>
nn <silent> xl :call LanguageClient#findLocations({'method':'$ccls/navigate','direction':'R'})<cr>

Custom cross references

" bases of up to 3 levels
nn <silent> xb :call LanguageClient#findLocations({'method':'$ccls/inheritanceHierarchy','flat':v:true,'levels':3,'derived':v:false})<cr>
" derived of up to 3 levels
nn <silent> xd :call LanguageClient#findLocations({'method':'$ccls/inheritanceHierarchy','flat':v:true,'levels':3,'derived':v:true})<cr>
nn <silent> xe :call LanguageClient#findLocations({'method':'$ccls/callers'})<cr>
nn <silent> xm :call LanguageClient#findLocations({'method':'$ccls/memberHierarchy','flat':v:true})<cr>
nn <silent> xt :call LanguageClient#textDocument_typeDefinition()<cr>
nn <silent> xv :call LanguageClient#findLocations({'method':'$ccls/vars'})<cr>
nn <silent> xV :call LanguageClient#findLocations({'method':'$ccls/vars','kind':1})<cr>
nn xx x