S: stream::Stream<Item = XmppCommand, Error = ()> + 'static,

    S: stream::Stream<Item = XmppCommand> + 'static,

                            future::ok(future::Loop::Break((None, conn.into())))

                            future::ok(future::Loop::Break(()))

    .and_then(|(opt_cmd_recv, _conn): (Option<S>, MaybeXmppConnection)| {
        if let Some(cmd_recv) = opt_cmd_recv {
            // process left commands
            info!("Stop accepting commands");
            Box::new(
                cmd_recv
                    .for_each(|_cmd| future::ok(()))
                    .map_err(|_| format_err!("cmd receiver last error")),
            ) as Box<Future<Item = (), Error = failure::Error>>
        } else {
            Box::new(future::ok(()))
        }
    })