reST リアルタイムでレンダリングする vim script

instant_rst.vim

python <<EOPython

import vim

class InstantReST(object):
    from multiprocessing import Queue

    queue = Queue()
    process = None
    last_rst = None

    @staticmethod
    def _process_main(queue):
        import os, sys
        # XXX: ignore docutils' warnings
        sys.stderr = open(os.devnull, 'w')

        import docutils.core
        import docutils.writers.html4css1
        import threading

        from gi.repository import GLib
        from gi.repository import Gtk
        from gi.repository import WebKit

        GLib.threads_init()

        w = Gtk.Window()
        w.set_size_request(640, 480)

        webview = WebKit.WebView()

        w.add(webview)
        w.connect('destroy', lambda *_: Gtk.main_quit())
        w.show_all()

        def q_watcher():
            while True:
                rst = queue.get()
                html = docutils.core.publish_string(rst, writer=docutils.writers.html4css1.Writer())

                # load string in main thread
                GLib.idle_add(webview.load_string, html, 'text/html', 'UTF-8', '')

        threading.Thread(target=q_watcher).start()
        Gtk.main()

    @classmethod
    def start_webview_process(cls):
        from multiprocessing import Process
        cls.process = Process(target=cls._process_main, args=(cls.queue, ))
        cls.process.start()

    @classmethod
    def view_rst(cls, rst):
        if cls.process is None or not cls.process.is_alive():
            # FIXME: by unknown reason, second process can't get from queue
            cls.start_webview_process()

        cls.queue.put(rst)

    @classmethod
    def update_view(cls):
        rst = '\n'.join(vim.current.buffer[:])
        if rst != cls.last_rst:
            cls.last_rst = rst
            cls.view_rst(rst)

    @classmethod
    def stop_view(cls):
        if cls.process is not None:
            # FIXME: process doesn't exit
            cls.process.terminate()

EOPython

autocmd CursorMoved,CursorMovedI,CursorHold,CursorHoldI *.rst silent python InstantReST.update_view()
autocmd BufWinEnter *.rst silent python InstantReST.update_view()
autocmd BufWinLeave *.rst silent python InstantReST.stop_view()