Extend interceptors.

Tests/MQTTnet.Core.Tests/Internal/AsyncLock_Tests.cs

@@ -4,7 +4,7 @@ using System.Threading.Tasks;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 using MQTTnet.Internal;
 
-namespace MQTTnet.Tests
+namespace MQTTnet.Tests.Internal
 {
     [TestClass]
     public class AsyncLock_Tests

Tests/MQTTnet.Core.Tests/Internal/AsyncQueue_Tests.cs

@@ -4,7 +4,7 @@ using System.Threading.Tasks;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 using MQTTnet.Internal;
 
-namespace MQTTnet.Tests
+namespace MQTTnet.Tests.Internal
 {
     [TestClass]
     public class AsyncQueue_Tests

Tests/MQTTnet.Core.Tests/Internal/MqttPacketBus_Tests.cs

@@ -0,0 +1,110 @@
+using System;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using MQTTnet.Internal;
+using MQTTnet.Packets;
+
+namespace MQTTnet.Tests.Internal
+{
+    [TestClass]
+    public sealed class MqttPacketBus_Tests
+    {
+        [TestMethod]
+        [ExpectedException(typeof(OperationCanceledException))]
+        public async Task Wait_With_Empty_Bus()
+        {
+            var bus = new MqttPacketBus();
+
+            using (var timeout = new CancellationTokenSource(TimeSpan.FromSeconds(1)))
+            {
+                await bus.DequeueAsync(timeout.Token);
+            }
+        }
+        
+        [TestMethod]
+        public void Alternate_Priorities()
+        {
+            var bus = new MqttPacketBus();
+            
+            bus.Enqueue(new MqttPacketBusItem(new MqttPublishPacket()), MqttPacketBusPartition.Data);
+            bus.Enqueue(new MqttPacketBusItem(new MqttPublishPacket()), MqttPacketBusPartition.Data);
+            bus.Enqueue(new MqttPacketBusItem(new MqttPublishPacket()), MqttPacketBusPartition.Data);
+            
+            bus.Enqueue(new MqttPacketBusItem(new MqttSubAckPacket()), MqttPacketBusPartition.Control);
+            bus.Enqueue(new MqttPacketBusItem(new MqttSubAckPacket()), MqttPacketBusPartition.Control);
+            bus.Enqueue(new MqttPacketBusItem(new MqttSubAckPacket()), MqttPacketBusPartition.Control);
+            
+            bus.Enqueue(new MqttPacketBusItem(new MqttPingRespPacket()), MqttPacketBusPartition.Health);
+            bus.Enqueue(new MqttPacketBusItem(new MqttPingRespPacket()), MqttPacketBusPartition.Health);
+            bus.Enqueue(new MqttPacketBusItem(new MqttPingRespPacket()), MqttPacketBusPartition.Health);
+
+            Assert.AreEqual(9, bus.PacketsCount);
+            
+            Assert.IsInstanceOfType(bus.DequeueAsync(CancellationToken.None).Result.Packet, typeof(MqttPublishPacket));
+            Assert.IsInstanceOfType(bus.DequeueAsync(CancellationToken.None).Result.Packet, typeof(MqttSubAckPacket));
+            Assert.IsInstanceOfType(bus.DequeueAsync(CancellationToken.None).Result.Packet, typeof(MqttPingRespPacket));
+            Assert.IsInstanceOfType(bus.DequeueAsync(CancellationToken.None).Result.Packet, typeof(MqttPublishPacket));
+            Assert.IsInstanceOfType(bus.DequeueAsync(CancellationToken.None).Result.Packet, typeof(MqttSubAckPacket));
+            Assert.IsInstanceOfType(bus.DequeueAsync(CancellationToken.None).Result.Packet, typeof(MqttPingRespPacket));
+            Assert.IsInstanceOfType(bus.DequeueAsync(CancellationToken.None).Result.Packet, typeof(MqttPublishPacket));
+            Assert.IsInstanceOfType(bus.DequeueAsync(CancellationToken.None).Result.Packet, typeof(MqttSubAckPacket));
+            Assert.IsInstanceOfType(bus.DequeueAsync(CancellationToken.None).Result.Packet, typeof(MqttPingRespPacket));
+            
+            Assert.AreEqual(0, bus.PacketsCount);
+        }
+        
+        [TestMethod]
+        public void Export_Packets_Without_Dequeue()
+        {
+            var bus = new MqttPacketBus();
+
+            bus.Enqueue(new MqttPacketBusItem(new MqttPublishPacket()), MqttPacketBusPartition.Data);
+            bus.Enqueue(new MqttPacketBusItem(new MqttPublishPacket()), MqttPacketBusPartition.Data);
+            bus.Enqueue(new MqttPacketBusItem(new MqttPublishPacket()), MqttPacketBusPartition.Data);
+            
+            Assert.AreEqual(3, bus.PacketsCount);
+
+            var exportedPackets = bus.ExportPackets(MqttPacketBusPartition.Control);
+            Assert.AreEqual(0, exportedPackets.Count);
+            
+            exportedPackets = bus.ExportPackets(MqttPacketBusPartition.Health);
+            Assert.AreEqual(0, exportedPackets.Count);
+            
+            exportedPackets = bus.ExportPackets(MqttPacketBusPartition.Data);
+            Assert.AreEqual(3, exportedPackets.Count);
+            
+            Assert.AreEqual(3, bus.PacketsCount);
+        }
+        
+        [TestMethod]
+        public void Await_Single_Packet()
+        {
+            var bus = new MqttPacketBus();
+
+            var delivered = false;
+            
+            bus.Enqueue(new MqttPublishPacket(), MqttPacketBusPartition.Data);
+            bus.Enqueue(new MqttPublishPacket(), MqttPacketBusPartition.Data);
+            bus.Enqueue(new MqttPublishPacket(), MqttPacketBusPartition.Data).Delivered += (_, __) =>
+            {
+                delivered = true;
+            };
+            
+            Assert.IsFalse(delivered);
+
+            bus.DequeueAsync(CancellationToken.None).Result.MarkAsDelivered();
+            
+            Assert.IsFalse(delivered);
+            
+            bus.DequeueAsync(CancellationToken.None).Result.MarkAsDelivered();
+            
+            Assert.IsFalse(delivered);
+            
+            bus.DequeueAsync(CancellationToken.None).Result.MarkAsDelivered();
+            
+            // The third packet has the event attached.
+            Assert.IsTrue(delivered);
+        }
+    }
+}