No way to get rid of the Wait.

src/Squidex.Infrastructure/CQRS/Events/Actors/EventConsumerActor.cs

@@ -100,6 +100,14 @@ namespace Squidex.Infrastructure.CQRS.Events.Actors
             }
         }
 
+        public async Task WaitForCompletionAsync()
+        {
+            while (dispatcher.InputCount > 0)
+            {
+                await Task.Delay(20);
+            }
+        }
+
         public Task SubscribeAsync(IEventConsumer eventConsumer)
         {
             Guard.NotNull(eventConsumer, nameof(eventConsumer));

tests/Squidex.Infrastructure.Tests/CQRS/Commands/AggregateHandlerTests.cs

@@ -87,7 +87,7 @@ namespace Squidex.Infrastructure.CQRS.Commands
 
             await sut.CreateAsync<MyDomainObject>(context, async x =>
             {
-                await Task.Delay(1);
+                await Task.Yield();
 
                 passedDomainObject = x;
             });
@@ -139,7 +139,7 @@ namespace Squidex.Infrastructure.CQRS.Commands
 
             await sut.UpdateAsync<MyDomainObject>(context, async x =>
             {
-                await Task.Delay(1);
+                await Task.Yield();
 
                 passedDomainObject = x;
             });

tests/Squidex.Infrastructure.Tests/CQRS/Events/Actors/EventConsumerActorTests.cs

@@ -207,6 +207,10 @@ namespace Squidex.Infrastructure.CQRS.Events.Actors
             await OnSubscribeAsync();
             await OnErrorAsync(eventSubscription, ex);
 
+            await Task.Delay(200);
+
+            await sut.WaitForCompletionAsync();
+
             sut.Dispose();
 
             A.CallTo(() => eventConsumerInfoRepository.SetAsync(consumerName, consumerInfo.Position, false, null))
@@ -341,25 +345,19 @@ namespace Squidex.Infrastructure.CQRS.Events.Actors
                 .MustHaveHappened(Repeated.Exactly.Twice);
         }
 
-        private async Task OnErrorAsync(IEventSubscription subscriber, Exception ex)
+        private Task OnErrorAsync(IEventSubscription subscriber, Exception ex)
         {
-            await sutSubscriber.OnErrorAsync(subscriber, ex);
-
-            await Task.Delay(200);
+            return sutSubscriber.OnErrorAsync(subscriber, ex);
         }
 
-        private async Task OnEventAsync(IEventSubscription subscriber, StoredEvent ev)
+        private Task OnEventAsync(IEventSubscription subscriber, StoredEvent ev)
         {
-            await sutSubscriber.OnEventAsync(subscriber, ev);
-
-            await Task.Delay(200);
+            return sutSubscriber.OnEventAsync(subscriber, ev);
         }
 
-        private async Task OnSubscribeAsync()
+        private Task OnSubscribeAsync()
         {
-            await sut.SubscribeAsync(eventConsumer);
-
-            await Task.Delay(200);
+            return sut.SubscribeAsync(eventConsumer);
         }
     }
 }

tests/Squidex.Infrastructure.Tests/CQRS/Events/PollingSubscriptionTests.cs

@@ -0,0 +1,68 @@
+// ==========================================================================
+//  PollingSubscriptionTests.cs
+//  Squidex Headless CMS
+// ==========================================================================
+//  Copyright (c) Squidex Group
+//  All rights reserved.
+// ==========================================================================
+
+using System;
+using System.Threading;
+using System.Threading.Tasks;
+using FakeItEasy;
+using Xunit;
+
+namespace Squidex.Infrastructure.CQRS.Events
+{
+    public class PollingSubscriptionTests
+    {
+        private readonly IEventStore eventStore = A.Fake<IEventStore>();
+        private readonly IEventNotifier eventNotifier = new DefaultEventNotifier(new InMemoryPubSub());
+        private readonly IEventSubscriber eventSubscriber = A.Fake<IEventSubscriber>();
+        private readonly PollingSubscription sut;
+        private readonly string position = Guid.NewGuid().ToString();
+
+        public PollingSubscriptionTests()
+        {
+            sut = new PollingSubscription(eventStore, eventNotifier, eventSubscriber, "^my-stream", position);
+        }
+
+        [Fact]
+        public async Task Should_subscribe_on_start()
+        {
+            await WaitAndStopAsync();
+
+            A.CallTo(() => eventStore.GetEventsAsync(A<Func<StoredEvent, Task>>.Ignored, A<CancellationToken>.Ignored, "^my-stream", position))
+                .MustHaveHappened(Repeated.Exactly.Once);
+        }
+
+        [Fact]
+        public async Task Should_not_subscribe_on_notify_when_stream_matches()
+        {
+            eventNotifier.NotifyEventsStored("other-stream-123");
+
+            await WaitAndStopAsync();
+
+            A.CallTo(() => eventStore.GetEventsAsync(A<Func<StoredEvent, Task>>.Ignored, A<CancellationToken>.Ignored, "^my-stream", position))
+                .MustHaveHappened(Repeated.Exactly.Once);
+        }
+
+        [Fact]
+        public async Task Should_subscribe_on_notify_when_stream_matches()
+        {
+            eventNotifier.NotifyEventsStored("my-stream-123");
+
+            await WaitAndStopAsync();
+
+            A.CallTo(() => eventStore.GetEventsAsync(A<Func<StoredEvent, Task>>.Ignored, A<CancellationToken>.Ignored, "^my-stream", position))
+                .MustHaveHappened(Repeated.Exactly.Twice);
+        }
+
+        private async Task WaitAndStopAsync()
+        {
+            await Task.Delay(1000);
+
+            await sut.StopAsync();
+        }
+    }
+}

tests/Squidex.Infrastructure.Tests/UsageTracking/BackgroundUsageTrackerTests.cs

@@ -112,8 +112,7 @@ namespace Squidex.Infrastructure.UsageTracking
             await sut.TrackAsync("key1", 0, 1000);
 
             sut.Next();
-
-            await Task.Delay(100);
+            sut.Dispose();
 
             A.CallTo(() => usageStore.TrackUsagesAsync(A<DateTime>.Ignored, A<string>.Ignored, A<double>.Ignored, A<long>.Ignored)).MustNotHaveHappened();
         }