sys_recv not called on Actor

[milgner]

Scenario: my actor registers a schedule and I was under the impression that I should cancel the schedule when the actor is shutting down. Unfortunately, Actor::post_stop doesn't have a reference to ActorSystem so I cannot cancel the schedule there.

It's possible that schedules for terminated actors get cleaned up automatically but during experimentation I realised that Actor::sys_recv doesn't get invoked even though the documentation suggests that it would be.

The following code only prints "Stopping the actor..." but not "System message!".

impl Actor for MyActor {
    type Msg = MyActorMsg;

    fn post_stop(&mut self) {
        println!("Stopping the actor for {}", self.configuration.uri);
        match self.schedule_id {
            Some(schedule_id) => {
                // TODO: how to cancel the schedule w/o reference to the ActorSystem?
                // ctx.system.cancel_schedule(schedule_id);
            }
            None => {
                warn!("Stopping the actor without any schedule running");
            }
        }
    }

    fn sys_recv(&mut self, ctx: &Context<Self::Msg>, msg: SystemMsg, sender: Sender) {
        println!("System message!");
    }

    fn recv(&mut self, ctx: &Context<Self::Msg>, msg: Self::Msg, sender: Sender) {
        self.receive(ctx, msg, sender)
    }
}