completion does not work due to hover.lua error

[gohm44]

init.vim

all plug#begin('~/.vim/plugged')
    Plug 'neovim/nvim-lsp'
    Plug 'nvim-lua/completion-nvim'
call plug#end()
lua require'lspconfig'.sumneko_lua.setup{on_attach=require'completion'.on_attach}
au Filetype lua setl omnifunc=v:lua.vim.lsp.omnifunc
" Use <Tab> and <S-Tab> to navigate through popup menu
inoremap <expr> <Tab>   pumvisible() ? "\<C-n>" : "\<Tab>"
inoremap <expr> <S-Tab> pumvisible() ? "\<C-p>" : "\<S-Tab>"

" Set completeopt to have a better completion experience
set completeopt=menuone,noinsert,noselect

nvim --version

NVIM v0.5.0-828-g0a95549d6
Build type: RelWithDebInfo
LuaJIT 2.1.0-beta3
Compilation: /usr/bin/gcc-5 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1 -O2 -g -Og -g -Wall -Wextra -pedantic -Wno-unused-parameter -Wstrict-prototypes -std=gnu99 -Wshadow -Wconversion -Wmissing-prototypes -Wvla -fstack-protector-strong -fno-common -fdiagnostics-color=auto -DINCLUDE_GENERATED_DECLARATIONS -D_GNU_SOURCE -DNVIM_MSGPACK_HAS_FLOAT32 -DNVIM_UNIBI_HAS_VAR_FROM -DMIN_LOG_LEVEL=3 -I/home/travis/build/neovim/bot-ci/build/neovim/build/config -I/home/travis/build/neovim/bot-ci/build/neovim/src -I/home/travis/build/neovim/bot-ci/build/neovim/.deps/usr/include -I/usr/include -I/home/travis/build/neovim/bot-ci/build/neovim/build/src/nvim/auto -I/home/travis/build/neovim/bot-ci/build/neovim/build/include
Compiled by travis@travis-job-abaca5c2-51e7-4cf1-bc06-8cf3e644ab24

Features: +acl +iconv +tui
See ":help feature-compile"

   system vimrc file: "$VIM/sysinit.vim"
  fall-back for $VIM: "/share/nvim"

Run :checkhealth for more info

How to reproduce run neovim with the given configuration

Description At start nvim throws an error and completion does not work.

Error detected while processing /home/gohm/.config/nvim/init.vim:
line    5:
E5108: Error executing lua ...hm/.vim/plugged/completion-nvim/lua/completion/hover.lua:250: attempt to index field 'handlers' (a nil value)

So I guess the root cause of an issue:

M.default_handler = vim.lsp.handlers[handler]

Remove of this line allows to avoid an error during launch but still, completion does not work.

[sl8vz]

Hi, See #274, the problem is because the nvim nightly with the matching API hasn't been released yet. Temporary workaround is possible.

[gil-air-may]

Same issue here :eyes:

[gohm44]

As @sl8vz pointed out we need a newer version of neovim. I did install neovim-git via AUR on arch and it resolved the issue.

[cyansprite]

The manual bash script way to install the latest and greatest of Neovim. I know they have a CMakeFile but it didn't work for me so I just did it manually this way, hope that helps.

git clone https://github.com/neovim/neovim.git
cd neovim
mkdir .deps
cd .deps
cmake ../third-party
make
cd ..
mkdir build
cd build
cmake ..
make
sudo make install
cd ../../
rm -rf neovim

You'll probably need these too

sudo apt install gperf luajit luarocks libuv1-dev libluajit-5.1-dev libunibilium-dev libmsgpack-dev libtermkey-dev libvterm-dev libutf8proc-dev