Investigate discussion #1793

Add a test to try and reproduce the `SemaphoreFullException`.

Author: lukebakken

projects/Test/Integration/GH/TestGitHubIssues.cs

@@ -329,5 +329,45 @@ await ch.BasicPublishAsync(exchange: string.Empty, routingKey: queueName,
                 _output.WriteLine("saw {0} publishExceptions", publishExceptions.Count);
             }
         }
+
+        [Fact]
+        public async Task MaybeSomethingUpWithRateLimiter_GH1793()
+        {
+            _connFactory = new ConnectionFactory
+            {
+                AutomaticRecoveryEnabled = true
+            };
+
+            _conn = await _connFactory.CreateConnectionAsync();
+
+            var channelOpts = new CreateChannelOptions(
+                publisherConfirmationsEnabled: true,
+                publisherConfirmationTrackingEnabled: true,
+                outstandingPublisherConfirmationsRateLimiter: new ThrottlingRateLimiter(256)
+            );
+
+            _channel = await _conn.CreateChannelAsync(channelOpts);
+
+            var properties = new BasicProperties
+            {
+                DeliveryMode = DeliveryModes.Persistent
+            };
+            int retryCount = 0;
+            const int maxRetries = 3;
+            while (retryCount <= maxRetries)
+            {
+                try
+                {
+                    var bytes = Encoding.UTF8.GetBytes("message");
+                    await _channel.BasicPublishAsync(string.Empty, string.Empty, true, properties, bytes);
+                    break;
+                }
+                catch (Exception ex)
+                {
+                    retryCount++;
+                    _output.WriteLine("{0} exception: {1}", _testDisplayName, ex);
+                }
+            }
+        }
     }
 }