Install coc.nvim
Open config file with command :CocConfig
{
"languageserver": {
"ccls": {
"command": "ccls",
"filetypes": ["c", "cpp", "cuda", "objc", "objcpp"],
"rootPatterns": [".ccls-root", "compile_commands.json"],
"initializationOptions": {
"cache": {
"directory": ".ccls-cache"
},
"client": {
"snippetSupport": true
}
}
}
}
}
Note: coc.nvim also supports configuration from .vimrc instead.
more about initializationOptions, see src/config.hh in ccls source code
First example:
cd /tmp; mkdir c; cd c
git init # let coc.nvim know this is a project
printf '#include <stddef.h>\nint main() {}\n' > a.cc
nvim a.cc
For a larger project, you'll need .ccls or compile_commands.json in your project root.
These features will work out-of-the-box. Find more on coc.nvim's README.
nmap <silent> <M-j> <Plug>(coc-definition)
nmap <silent> <C-,> <Plug>(coc-references)
nn <silent> K :call CocActionAsync('doHover')<cr>
textDocument/documentHighlight
set updatetime=300
au CursorHold * sil call CocActionAsync('highlight')
au CursorHoldI * sil call CocActionAsync('showSignatureHelp')
Completion
See client.snippetSupport and completion.placeholder for customization of snippet expansion.
Cross reference extensions
See LSP Extensions for the description of these extensions.
" bases
nn <silent> xb :call CocLocations('ccls','$ccls/inheritance')<cr>
" bases of up to 3 levels
nn <silent> xB :call CocLocations('ccls','$ccls/inheritance',{'levels':3})<cr>
" derived
nn <silent> xd :call CocLocations('ccls','$ccls/inheritance',{'derived':v:true})<cr>
" derived of up to 3 levels
nn <silent> xD :call CocLocations('ccls','$ccls/inheritance',{'derived':v:true,'levels':3})<cr>
" caller
nn <silent> xc :call CocLocations('ccls','$ccls/call')<cr>
" callee
nn <silent> xC :call CocLocations('ccls','$ccls/call',{'callee':v:true})<cr>
" $ccls/member
" member variables / variables in a namespace
nn <silent> xm :call CocLocations('ccls','$ccls/member')<cr>
" member functions / functions in a namespace
nn <silent> xf :call CocLocations('ccls','$ccls/member',{'kind':3})<cr>
" nested classes / types in a namespace
nn <silent> xs :call CocLocations('ccls','$ccls/member',{'kind':2})<cr>
nmap <silent> xt <Plug>(coc-type-definition)<cr>
nn <silent> xv :call CocLocations('ccls','$ccls/vars')<cr>
nn <silent> xV :call CocLocations('ccls','$ccls/vars',{'kind':1})<cr>
nn xx x
$ccls/navigate
See $ccls/navigate
nn <silent><buffer> <C-l> :call CocLocations('ccls','$ccls/navigate',{'direction':'D'})<cr>
nn <silent><buffer> <C-k> :call CocLocations('ccls','$ccls/navigate',{'direction':'L'})<cr>
nn <silent><buffer> <C-j> :call CocLocations('ccls','$ccls/navigate',{'direction':'R'})<cr>
nn <silent><buffer> <C-h> :call CocLocations('ccls','$ccls/navigate',{'direction':'U'})<cr>
Customization with coc.nvim
Options listed in Customization can be passed to CCLS via initializationOptions in the Coc configuration file. For example, if to direct ccls to look for compile_commands.json in the project build directory, you could add an entry for compilationDatabaseDirectory, and update rootPatterns accordingly.
{
"languageserver": {
"ccls": {
"command": "ccls",
"filetypes": ["c", "cpp", "cuda", "objc", "objcpp"],
"rootPatterns": [".ccls-root", "build/compile_commands.json"],
"initializationOptions": {
"cache": {
"directory": ".ccls-cache"
},
"client": {
"snippetSupport": true
},
"compilationDatabaseDirectory": "build"
}
}
}
}
Options like clang.extraArgs may be similarly be added using the same syntax as client.snippetSupport in the example above. For example, we can support C++20 by default by passing -std=c++20 as an extra argument to clang:
{
"languageserver": {
"ccls": {
"command": "ccls",
"filetypes": ["c", "cpp", "cuda", "objc", "objcpp"],
"rootPatterns": [".ccls-root", "build/compile_commands.json"],
"initializationOptions": {
"cache": {
"directory": ".ccls-cache"
},
"client": {
"snippetSupport": true
},
"compilationDatabaseDirectory": "build",
"clang": {
"extraArgs": [ "-std=c++20" ]
}
}
}
}
}