fixed #691

Tests/MQTTnet.AspNetCore.Tests/Mockups/LimitedMemoryPool.cs

@@ -0,0 +1,18 @@
+using System.Buffers;
+
+namespace MQTTnet.AspNetCore.Tests.Mockups
+{
+    public class LimitedMemoryPool : MemoryPool<byte>
+    {
+        protected override void Dispose(bool disposing)
+        {
+        }
+
+        public override IMemoryOwner<byte> Rent(int minBufferSize = -1)
+        {
+            return new MemoryOwner(minBufferSize);
+        }
+
+        public override int MaxBufferSize { get; }
+    }
+}