coc.nvim.autocomplete.map

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

inoremap <expr><S-TAB> pumvisible() ? "\<C-p>" : "\<C-h>"

" inoremap <expr> <TAB> pumvisible() ? "\<C-y>" : "\<C-g>u\<TAB>"

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

let g:coc_snippet_next = '<tab>'