`nvim` launcher python script

nvim.py

#!/usr/bin/env python3
import neovim
import os
import sys

args = sys.argv[1:]
wait = 0
exitcode = 0

vimexe = "/usr/bin/nvim"
addr_env = 'NVIM'

if addr_env in os.environ:
    addr = os.environ[addr_env]
    if ":" in addr:
        split = addr.split(":")
        nvim = neovim.attach('tcp', address=split[0], port=split[1])
    else:
        nvim = neovim.attach('socket', path=os.environ[addr_env])

    def open_files(inbetween, on_every):
        global wait
        first = True
        for file in args:
            if not first:
                inbetween()
            first = False
            file = os.path.abspath(file)
            nvim.command('edit {}'.format(file))
            bvars = nvim.current.buffer.vars
            chanid = nvim.channel_id

            nvim.command('augroup nvr')
            nvim.command('autocmd BufDelete <buffer> silent! call rpcnotify({}, "BufDelete")'.format(chanid))
            nvim.command('autocmd VimLeave * if exists("v:exiting") && v:exiting > 0 | silent! call rpcnotify({}, "Exit", v:exiting) | endif'.format(chanid))
            nvim.command('augroup END')

            if 'nvr' in bvars:
                if chanid not in bvars['nvr']:
                    bvars['nvr'] = [chanid] + bvars['nvr']
            else:
                bvars['nvr'] = [chanid]
            on_every(file)

    onclose = lambda: None

    if len(args) >= 1 and args[0] == "-d":
        args = args[1:]
        nvim.command('TabooOpen review')

        def inbetween():
            nvim.command('vsplit')

        def on_every(filename):
            nvim.command('diffthis')
            if filename.endswith(".ml.new-tip") or filename.endswith(".ml.old-tip") or filename.endswith(".mli.old-tip") or filename.endswith(".mli.new-tip"):
                nvim.command('set filetype=ocaml')


        open_files(inbetween, on_every)
        onclose = lambda: nvim.command('tabclose')
    else:
        def inbetween():
            return None

        def on_every(filename):
            global wait
            wait += 1
            return None
        open_files(inbetween, on_every)

    def notification_cb(msg, args):
        global wait
        global exitcode
        if msg == 'BufDelete':
            wait -= 1
            if wait <= 0:
                onclose()
                nvim.stop_loop()
                if len(args) == 0:
                    exitcode = 0
                else:
                    exitcode = args[0]

    def err_cb(error):
        global exitcode
        nvim.stop_loop()
        exitcode = 1
    nvim.run_loop(None, notification_cb, None, err_cb)
    nvim.close()
    sys.exit(exitcode)
else:
    os.execvp(vimexe, [vimexe, '-u', '~/.config/nvim/init.lua'] + args)