tab key will freeze nvim

[krisfans]

see hrsh7th/vim-vsnip#214

[krisfans]

I just update this plugin , a new problem appears . The same stpes , nvim report a error "E5108: Error executing lua ...pos/github.com/hrsh7th/nvim-cmp/lua/cmp/utils/keymap.lua:163: Vim:E121: Undefined variable: Tab"

[hrsh7th]

@krisfans Thank you for your report. It's very insightful.

Sorry for annoying but Could you check with the following debug codes?

-- keymap.lua:L162
misc.set(_G, { 'cmp', 'utils', 'keymap', 'evacuate', 'expr' }, function(mode, lhs, rhs)
  return keymap.t(keymap.recursive(mode, lhs, vim.api.nvim_eval(rhs)))
end)

↓↓↓

misc.set(_G, { 'cmp', 'utils', 'keymap', 'evacuate', 'expr' }, function(mode, lhs, rhs)
  print(rhs)
  return keymap.t(keymap.recursive(mode, lhs, vim.api.nvim_eval(rhs)))
end)

[krisfans]

vsnip#jumpable(1)? '(vsnip-jump-next)' : ''
E5108: Error executing lua ...pos/github.com/hrsh7th/nvim-cmp/lua/cmp/utils/keymap.lua:167: Vim:E121: Undefined variable: Tab

[rti]

Thank you so much for looking into this.

I think I run into a similar issue here:

from my init.lua

local cmp = require'cmp'

cmp.setup({
  snippet = {
    expand = function(args)
      vim.fn["vsnip#anonymous"](args.body)
    end,
  },

  mapping = {
    ['<C-d>'] = cmp.mapping.scroll_docs(-4),
    ['<C-f>'] = cmp.mapping.scroll_docs(4),
    ['<C-Space>'] = cmp.mapping.complete(),
    ['<C-e>'] = cmp.mapping.close(),
    ['<CR>'] = cmp.mapping.confirm({ select = true }),
    ['<C-j>'] = cmp.mapping.confirm({ select = true }),
    ['<TAB>'] = cmp.mapping.confirm({ select = true }),   -- removing this line fixes the issue
  },

  sources = {
    { name = 'nvim_lsp' },
    { name = 'vsnip' },
    { name = 'buffer' },
  }
})

In insert mode, press <TAB>, nvim freezes @ 100% CPU.
I am on cc21a61.
I do not get any error messages though.
Adding the print line mentioned above does not lead to any output here.

[hrsh7th]

@rti Thank you for pointing me it. Unfortunately, I can't reproduce the issue.
Can you still reproduce this issue with latest nvim-cmp?

[rti]

Sorry. Apparently I was hiding the most interesting part of my init.lua from you.

Yes, I am on the latest revision (cc21a61). Nvim 0.5.1.

The issue seems to be triggered by me configuring vsnip to react on <TAB> as well. Not sure whether my desired setting is possible at all, but from a user perspective, it would be very convenient :)

Minimal init.lua to reproduce the issue. It will install vim-plug on the first run in data path.
Disabling either cmp's or vsnip's <TAB> mapping prevents the freeze.

local cmd = vim.cmd
local call = vim.call
local fn = vim.fn

local scopes = {o = vim.o, b = vim.bo, w = vim.wo}

local function opt(scope, key, value)
  scopes[scope][key] = value
  if scope ~= 'o' then scopes['o'][key] = value end
end

opt('o', 'completeopt', 'menu,menuone,noselect')

local install_path = fn.stdpath('data') .. '/site/autoload/'
local install_file = install_path .. 'plug.vim'

if fn.empty(fn.glob(install_file)) > 0 then
  cmd[[echom 'Installing vim-plug']]
  fn.system({'mkdir', '-p', install_path})
  fn.system({
    'curl',
    '-fLo',
    install_file,
    'https://raw.githubusercontent.com/junegunn/vim-plug/master/plug.vim'
  })
end

local Plug = fn['plug#']

call('plug#begin', '~/.config/nvim/plugged')

Plug 'hrsh7th/nvim-cmp'
Plug 'hrsh7th/cmp-vsnip'
Plug 'hrsh7th/vim-vsnip'

call('plug#end')

local cmp = require'cmp'

cmp.setup({
  snippet = {
    expand = function(args)
      vim.fn["vsnip#anonymous"](args.body)
    end,
  },

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

  sources = {
    { name = 'vsnip' },
  }
})

cmd[[imap <expr> <Tab> vsnip#jumpable(1) ? '<Plug>(vsnip-jump-next)' : '<Tab>']]

Load with nvim -u, enter insert mode, press <TAB>, nvim will freeze. At least on my machine :)

[hrsh7th]

It's reproduced. Thank you. I will tackle it.

[rti]

Awesome. Indeed. It is fixed. My <TAB> key can now trigger completion AND jump the snipped.

Thank you so much ❤️

[gmorer]

Hello I ran into that issue today, when i press the TAB key without the the cmp popup, my neovim do freeze, filling the log file with Executing: call v:lua.cmp.utils.keymap.listen.run(23592651)
I can reproduce with the following conf:

mapping = {
   ['<Tab>'] = cmp.mapping.select_next_item()
}

my nvim version is v0.5.1
and nvim cmp local HEAD is at 4ecf2a2 (Sun Oct 17)

[hrsh7th]

I'll try it with minimal config.

[Diomendius]

I think I'm encountering the same issue. I use <c-n> / <c-p>, but otherwise the symptoms are the same. <c-c> will un-freeze Nvim, by the way.

In my case, it is a regression. Bisecting shows that 5fe7dc1 is the first bad commit.

[hrsh7th]

Please minimal reproduction configuration...

[Diomendius]

Use this init.vim:

lua << EOF
local cmp = require('cmp')
cmp.setup {
	mapping = {
		['<c-n>'] = cmp.mapping.select_next_item(),
	},
}
EOF

This assumes cmp is already loaded, so if it isn't already available in runtimepath or packpath, symlink/copy it there first.

To test it on my end, I made a temporary directory containing the following:

• nvim/init.vim (contents from above)
• pack/packs/start/nvim-cmp (the root of this repo, copied/symlinked/wget'd/whatever)

Then, I ran XDG_CONFIG_HOME=$NVIM_TEST XDG_DATA_HOME=$NVIM_TEST nvim, where $NVIM_TEST is the temporary directory I described above.

Nvim should freeze when typing CTRL-N in Insert mode. CTRL-C should unfreeze Nvim.

This is probably reproducible with any config that binds select_next_item() or select_prev_item(), but I can definitely reproduce it with this config.

[ghost]

Hello I ran into that issue today, when i press the TAB key without the the cmp popup, my neovim do freeze, filling the log file with Executing: call v:lua.cmp.utils.keymap.listen.run(23592651) I can reproduce with the following conf:

mapping = {
   ['<Tab>'] = cmp.mapping.select_next_item()
}

my nvim version is v0.5.1 and nvim cmp local HEAD is at 4ecf2a2 (Sun Oct 17)

Same Isssue persists for neovim for latest commit.

[hrsh7th]

I can't reproduce the issue with the following configuration.

I can't fix if the user doesn't provide minimal reproducible configuration.

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'
call plug#end()

lua <<EOF
local cmp = require("cmp")
cmp.setup({
  mapping = {
    ['<c-n>'] = cmp.mapping.select_next_item(),
    ['<C-p>'] = cmp.mapping.select_prev_item(),
    ['<C-d>'] = cmp.mapping.scroll_docs(-4),
    ['<C-f>'] = cmp.mapping.scroll_docs(4),
    ['<C-Space>'] = cmp.mapping.complete(),
    ['<C-e>'] = cmp.mapping.abort(),
    ['<CR>'] = cmp.mapping.confirm({ select = true }),
    ['<C-y>'] = cmp.mapping.confirm({ select = true }),
  },
  sources = {
    { name = 'buffer' }
  }
})
EOF

[hrsh7th]

Sorry... reproduced.

[gmorer]

The issue is stil present (i did update to latest) with:

['<Tab>'] = cmp.mapping.select_next_item(),
['<S-Tab>'] = cmp.mapping.select_prev_item(),

and with:

['<Tab>'] = function(fallback)
    if cmp.visible() then
         cmp.mapping.select_next_item()
      else
         fallback()
      end
 end,
['<S-Tab>'] = function(fallback)
      if cmp.visible() then
         cmp.mapping.select_prev_item()
      else
         fallback()
      end
end,

Same return in the log, it fill the log in an endless loop with Executing: call v:lua.cmp.utils.keymap.listen.run(12475286)

I recorded the log just before it strat to write that line endlessly: https://pastebin.com/dfUP8HEd

[hrsh7th]

What is the HighlightMatchingPairs?
I will try it with your config.

[gmorer]

From neovim sourcecode The function that is invoked (very often) to define a ":match" highlighting for any matching paren., look like it's call on thoses events: autocmd! CursorMoved,CursorMovedI,WinEnter * call s:Highlight_Matching_Pair() and autocmd! TextChanged,TextChangedI * call s:Highlight_Matching_Pair()
From neovim report in runtime/plugin/matchparen.vim