Code cleanup.

Source/MQTTnet.Tests/Formatter/MqttPacketSerialization_V3_Binary_Tests.cs

@@ -17,6 +17,7 @@ using MQTTnet.Internal;
 using MQTTnet.Packets;
 using MQTTnet.Protocol;
 using MQTTnet.Tests.Extensions;
+using MQTTnet.Tests.Mockups;
 
 namespace MQTTnet.Tests
 {

Source/MQTTnet.Tests/Mockups/TestMqttChannel.cs

@@ -0,0 +1,57 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.IO;
+using System.Security.Cryptography.X509Certificates;
+using System.Threading;
+using System.Threading.Tasks;
+using MQTTnet.Channel;
+
+namespace MQTTnet.Tests.Mockups
+{
+    public sealed class TestMqttChannel : IMqttChannel
+    {
+        readonly MemoryStream _stream;
+
+        public TestMqttChannel(MemoryStream stream)
+        {
+            _stream = stream;
+        }
+
+        public TestMqttChannel(byte[] buffer)
+        {
+            _stream = new MemoryStream(buffer);
+        }
+
+        public string Endpoint { get; } = "<Test channel>";
+
+        public bool IsSecureConnection { get; } = false;
+
+        public X509Certificate2 ClientCertificate { get; }
+
+        public Task ConnectAsync(CancellationToken cancellationToken)
+        {
+            return Task.FromResult(0);
+        }
+
+        public Task DisconnectAsync(CancellationToken cancellationToken)
+        {
+            return Task.FromResult(0);
+        }
+
+        public Task<int> ReadAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)
+        {
+            return _stream.ReadAsync(buffer, offset, count, cancellationToken);
+        }
+
+        public Task WriteAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)
+        {
+            return _stream.WriteAsync(buffer, offset, count, cancellationToken);
+        }
+
+        public void Dispose()
+        {
+        }
+    }
+}

Source/MQTTnet.Tests/MqttPacketSerializationHelper.cs

@@ -5,6 +5,7 @@ using MQTTnet.Diagnostics;
 using MQTTnet.Formatter;
 using MQTTnet.Internal;
 using MQTTnet.Packets;
+using MQTTnet.Tests.Mockups;
 
 namespace MQTTnet.Tests
 {