Line source for ddu.vim
This source collects current buffer lines.
https://github.com/vim-denops/denops.vim
https://github.com/Shougo/ddu.vim
https://github.com/Shougo/ddu-kind-file
call ddu#start(#{ 'sources': [#{ name: 'line' }] })