private void PacketReceive_EventCanceled <TPacket, TEvent>(TPacket packet, IPlayer sender)
            where TPacket : IPacket
            where TEvent : Event
        {
            Action <PacketReceiveEvent <TPacket> >?registeredHandler = null;

            var events = Mock.Of <IEventManager>();
            var log    = Mock.Of <ILogger>();

            Mock.Get(events)
            .Setup(em => em.RegisterHandler(It.IsAny <Action <PacketReceiveEvent <TPacket> > >(), log))
            .Callback <Action <PacketReceiveEvent <TPacket> >, ILogger>(
                (handler, log) => registeredHandler = handler);

            using var signService = new OrionSignService(events, log);

            var evt = new PacketReceiveEvent <TPacket>(packet, sender);

            Mock.Get(events)
            .Setup(em => em.Raise(It.IsAny <TEvent>(), log))
            .Callback <TEvent, ILogger>((evt, log) => evt.Cancel());

            Assert.NotNull(registeredHandler);
            registeredHandler !(evt);

            Assert.True(evt.IsCanceled);

            Mock.Get(events).VerifyAll();
        }