My custom Vsnip completion mapping function no longer works since commit db261b4

[bluz71]

FAQ

• I have checked the FAQ and it didn't resolve my problem.

Announcement

• I have checked Breaking change announcement.

Minimal reproducible full config

if has('vim_starting')
  set encoding=utf-8
endif
scriptencoding utf-8

if &compatible
  set nocompatible
endif

let s:plug_dir = expand('/tmp/plugged/vim-plug')
if !filereadable(s:plug_dir .. '/plug.vim')
  execute printf('!curl -fLo %s/autoload/plug.vim --create-dirs https://raw.githubusercontent.com/junegunn/vim-plug/master/plug.vim', s:plug_dir)
end

execute 'set runtimepath+=' . s:plug_dir
call plug#begin(s:plug_dir)
Plug 'hrsh7th/nvim-cmp'
Plug 'hrsh7th/cmp-buffer'
Plug 'hrsh7th/cmp-nvim-lsp'
Plug 'hrsh7th/vim-vsnip'
Plug 'neovim/nvim-lspconfig'
Plug 'hrsh7th/cmp-vsnip'
call plug#end()
PlugInstall | quit

" Setup global configuration. More on configuration below.
lua << EOF
local cmp = require "cmp"
cmp.setup {
  snippet = {
    expand = function(args)
      vim.fn["vsnip#anonymous"](args.body)
    end,
  },

  mapping = {
    ['<CR>'] = cmp.mapping.confirm({ select = true })
  },

  sources = cmp.config.sources({
    { name = "nvim_lsp" },
    { name = "buffer" },
  }),
}
EOF

function! VsnipComplete() abort
    let l:word_to_complete = matchstr(strpart(getline('.'), 0, col('.') - 1), '\S\+$')
    let l:contain_word = 'stridx(v:val.word, l:word_to_complete) >= 0'
    let l:candidates = vsnip#get_complete_items(bufnr('%'))
    let l:candidates = map(filter(l:candidates, l:contain_word),
                  \  "{
                  \      'word': v:val.word,
                  \      'menu': v:val.kind,
                  \      'dup' : 1,
                  \   }")
    let l:from_where = col('.') - len(l:word_to_complete)
    if !empty(l:candidates)
        call complete(l:from_where, l:candidates)
    endif

    return ''
endfunction

inoremap <silent> <C-s> <C-r>=VsnipComplete()<CR>

Description

Ever since commit db261b4 my custom <C-s> mapping no longer works.

Note, this is the same mapping that was provided in this Reddit post.

It appears the native popup menu quickly appears, then disappears (I think).

Steps to reproduce

Open a file with some vsnip snippets and then hit <Control-s> whilst in insert mode. Notice, no completion menu.

Now do the same with commit 27bc575. Notice, the completion menu appears (with snippets).

Expected behavior

Native completion menu should appear.

Actual behavior

Native completion does not appear (or is immediately closed).

Additional context

Hopefully it is just a simple tweak to the VsnipComplete function.

[bluz71]

Ok @hrsh7th, thanks for that.

Hopefully you find a longer-term fix.

Best regards.