Deoplete is a good auto-completion plugin for Neovim. In this post, I introduce how to set up auto-completion for Nvim with the help of deoplete.

Strictly speaking, it is an auto-completion engine. In order to enable auto-completion for a certain programming language, you need to install the corresponding source.

Install Deoplete

To use deoplete, you should make sure that you are using Python3 . You need to install pynvim – the Python client to Neovim:

pip3 install --user pynvim

Deoplete is easy to install. You can install deoplete with vim-plug:

Plug 'Shougo/deoplete.nvim', { 'do': ':UpdateRemotePlugins' }

Since deoplete is a completion engine. In order to use auto-completion for a specific language, you need to install the corresponding source for it. The complete list of sources supporting deoplete can be found here.

Follow the guide of the specific completion source to install it and enable completion for that language. For example, you can check here on how to set up deoplete and deoplete-jedi for Python auto-completion.

The minimum settings on deoplete’s side is to enalbe it at the start of Nvim:

let g:deoplete#enable_at_startup = 1

Other settings

Disable buffer and around source

The buffer and around source for deoplete is of little use for auto-completion. I would rather ignore them. To ignore these two sources, use the following settings

call deoplete#custom#option('ignore_sources', {'_': ['around', 'buffer']})

References

change the max width of the completion window

Sometimes, the completion term has long strings which are cut down due to limited completion window width. So change the max width allowed for completion window, use the following settings:

" maximum candidate window length
call deoplete#custom#source('_', 'max_menu_width', 80)

References