GVim starts slowly with enable_for_buffer()

If you’re having trouble with NCM2, Please provide the following information along with your detailed issue description:

OS

Windows 10 Pro 1803

neovim :version output

GVim 8.1 with patch 1-116

Minimal vimrc for reproducing the issue

set nocompatible
set fileformat=unix
set fileformats=unix,dos
set encoding=utf-8

call plug#begin('E:\ProgramFiles\Vim\vimfiles\plugged')
Plug 'ncm2/ncm2'
Plug 'roxma/nvim-yarp'
Plug 'roxma/vim-hug-neovim-rpc'
call plug#end()

autocmd BufEnter * call ncm2#enable_for_buffer()

neovim :messages output when the error occurs

N/A.

Log files if you think the issue is a bug

gvim --startuptime log.txt

with and without the autocmd BufEnter * call ncm2#enable_for_buffer().

Additional description

In short, is there a solution to make this autocmd work without slowing down the startup?

Basically, with autocmd BufEnter * call ncm2#enable_for_buffer() in my full vimrc, it could take as much as about 2.6s to start GVim while it takes only about 500ms to start without this autocmd. However, it is necessary to put this autocmd in my vimrc since I usually load a session before working.

Startup timing log files of minimal vimrc are attached below. Thanks in advanced.

log.txt log_wo.txt

[YaLTeR]

I believe I’m hitting the same issue, with neovim-gtk, except it straight up hits a timeout and shows an error message with

autocmd BufEnter * call ncm2#enable_for_buffer()

so it’s rather critical. Launching nvim in terminal works fine.

autocmd InsertEnter * call ncm2#enable_for_buffer()

seems to work too but it’s a workaround.

Edit: turns out the InsertEnter workaround doesn’t work very well: it makes the LSP completions not show up until the language client is manually restarted (probably due to it initializing before ncm2). I switched to the timer workaround.

[roxma]

Hmm…

If you don’t want ncm2 to start as vim starts.

Try something like

    function s:ncm2_start(...)
        if v:vim_did_enter
            call ncm2#enable_for_buffer()
        endif
        autocmd BufEnter * call ncm2#enable_for_buffer()
    endfunc
    call timer_start(500, function('s:ncm2_start'))

or

autocmd InsertEnter * call ncm2#enable_for_buffer()