core.py 文件源码

def add_cog(self, cls):
        """Tries to load a cog.

        If not all dependencies are loaded, will defer until they are.
        """
        desc = getattr(cls, PLUGIN_DESC, None)
        if not desc:
            log.debug("Loading cog %s", cls)
            return super().add_cog(cls)

        depends = [self.get_cog(name) for name in desc.depends]
        if not all(depends):
            self._dango_unloaded_cogs[cls.__name__] = cls
            return

        self._config.load()
        cgroup = self._config.root.add_group(utils.snakify(cls.__name__))

        depends.insert(0, cgroup)
        if desc.pass_bot:
            depends.insert(0, self)

        try:
            cog = cls(*depends)
        except config.InvalidConfig:
            raise
        finally:
            self._config.save()
        super().add_cog(cog)
        setattr(cog, COG_DESC, CogDesc(datetime.datetime.utcnow()))
        log.debug("Loaded dcog %s.%s", cls.__module__, cls.__name__)

        # Try loading previously unloaded plugins.
        unloaded_plugins = self._dango_unloaded_cogs
        self._dango_unloaded_cogs = {}
        for plugin in unloaded_plugins.values():
            self.add_cog(plugin)