How to stop lualine from flickering when selecting options in the coc menu?

[skamsie]

I am using lualine and each time I navigate through the coc menu with Ctrl-P Ctrl-N my status line flickers. I can see it is because with each movement in the coc menu it briefly enters command mode so the status line updates from 'normal' to 'command' and viceversa... Is there a way to prevent this?

my coc settings are minimal:

return {
  'neoclide/coc.nvim',
  config = function()
    vim.g.coc_global_extensions = {
      'coc-clangd',
      'coc-css',
      'coc-html',
      'coc-lua',
      'coc-solargraph',
      'coc-solargraph',
      'coc-vimlsp',
    }

    vim.cmd[[
      nmap <silent> gd <Plug>(coc-definition)
      nmap <silent> gy <Plug>(coc-type-definition)
      nmap <silent> gi <Plug>(coc-implementation)
      nmap <silent> gr <Plug>(coc-references)
    ]]
  end
}

Screen.Recording.2024-10-17.at.20.53.34.mov

[hexh250786313]

@skamsie Hi.

inoremap <silent><expr> <TAB>
      \ coc#pum#visible() ? coc#pum#next(1) :
      \ CheckBackspace() ? "\<Tab>" :
      \ coc#refresh()
inoremap <expr><S-TAB> coc#pum#visible() ? coc#pum#prev(1) : "\<C-h>"

I guess your coc configuration code is similar to the above configuration. The issue lies in the coc#pum#next and coc#pum#prev functions. Let's take a look at their source code:

coc.nvim/autoload/coc/pum.vim

Lines 134 to 136 in 3b8869a

	function! coc#pum#next(insert) abort
	return "\<C-r>=coc#pum#_navigate(1,".a:insert.")\<CR>"
	endfunction

In fact, they call \<C-r>=coc#pum#_navigate(1,".a:insert.")\<CR>, which can be understood as executing :call xxxxx in the vim command. Using : as the command prefix will cause lualine to flicker. This is not only an issue with coc, but other plugins and even your custom commands may have this problem. Therefore, I recommend using <cmd>call xxx to call functions, which will avoid the flickering issue. Of course, I think it would be better for lualine to solve this problem itself.

Back to the coc issue, you can try modifying your configuration by changing coc#pum#next() and coc#pum#prev() to:

inoremap <silent><expr> <TAB>
  \ coc#pum#visible() ? "<cmd>call coc#pum#_navigate(1,0)<cr>" :
  \ CheckBackspace() ? "\<Tab>" :
  \ coc#refresh()
inoremap <expr><S-TAB> coc#pum#visible() ? "<cmd>call coc#pum#_navigate(0,0)<cr>" : "\<C-h>"

This way, the original functions are called through <cmd>, which should avoid the flickering issue. Although this is not the optimal solution, it can temporarily solve your problem.

[skamsie]

thanks for your reply, but I already posted my coc settings in the original message and I do not have any custom key bindings, I just use Ctrl-N and Ctrl-P. In any case, the problem seems to be with lualine and I opened an issue there nvim-lualine/lualine.nvim#1313

[hexh250786313]

@skamsie

It might be that I didn't explain it clearly enough before. What I mean is that whether it's the default keymap of coc or your custom keymap, as long as it uses the coc#pum#prev and coc#pum#next keymaps, this issue will occur.

coc.nvim/plugin/coc.vim

Lines 710 to 715 in 3b8869a

	if empty(mapcheck('<C-n>', 'i'))
	inoremap <silent><expr> <C-n> coc#pum#visible() ? coc#pum#next(1) : "\<C-n>"
	endif
	if empty(mapcheck('<C-p>', 'i'))
	inoremap <silent><expr> <C-p> coc#pum#visible() ? coc#pum#prev(1) : "\<C-p>"
	endif

You can see in the coc source code that these two keymaps are bound by default. So, as I mentioned above, you can set a keymap to override these two keymaps, and this issue will not occur. The functionality of these two is exactly the same; the only difference is that the command prefix is changed from : to <cmd>:

inoremap <silent><expr> <C-n> coc#pum#visible() ? "<cmd>call coc#pum#_navigate(1,0)<cr>" : "\<C-n>" 
inoremap <silent><expr> <C-p> coc#pum#visible() ? "<cmd>call coc#pum#_navigate(0,0)<cr>" : "\<C-p>" 

20241105_113505.mp4