coc-snippests.vim

" Use <C-l> for trigger snippet expand.
imap <C-l> <Plug>(coc-snippets-expand)

" Use <C-j> for select text for visual placeholder of snippet.
vmap <C-j> <Plug>(coc-snippets-select)

" Use <C-j> for jump to next placeholder, it's default of coc.nvim
let g:coc_snippet_next = '<c-j>'

" Use <C-k> for jump to previous placeholder, it's default of coc.nvim
let g:coc_snippet_prev = '<c-k>'

" Use <C-j> for both expand and jump (make expand higher priority.)
imap <C-j> <Plug>(coc-snippets-expand-jump)

inoremap <silent><expr> <TAB>
      \ pumvisible() ? coc#_select_confirm() :
      \ coc#expandableOrJumpable() ? "\<C-r>=coc#rpc#request('doKeymap', ['snippets-expand-jump',''])\<CR>" :
      \ <SID>check_back_space() ? "\<TAB>" :
      \ coc#refresh()

function! s:check_back_space() abort
  let col = col('.') - 1
  return !col || getline('.')[col - 1]  =~# '\s'
endfunction

let g:coc_snippet_next = '<tab>'