public void SubscriptionCollection_CreateReport_Test()
        {
            var target = new SubscriptionCollection(new MessageBus());

            target.Subscribe <int>(b => b
                                   .WithTopic("test1")
                                   .Invoke(x => { }));
            target.Listen <int, string>(b => b
                                        .WithTopic("test2")
                                        .Invoke(x => "ok"));
            target.Participate <long, DateTime>(b => b
                                                .WithTopic("test3")
                                                .Invoke(x => DateTime.UtcNow));

            var report = target.ReportContents();

            report.Length.Should().Be(3);
        }