Saga scenario testing framework can't handle ReplyToOriginator

src/NServiceBus.Testing.Tests/Sagas/ReplyToOriginator.cs

@@ -0,0 +1,84 @@
+namespace NServiceBus.Testing.Tests.Sagas
+{
+    using System;
+    using System.Collections.Generic;
+    using System.Linq;
+    using System.Threading.Tasks;
+    using NUnit.Framework;
+
+    [TestFixture]
+    public class ReplyToOriginator
+    {
+        [Test]
+        public async Task ReplyToOriginatorShouldReplyToInitialOriginator()
+        {
+            const string originatorAddress = "expectedReplyAddress";
+
+            var saga = new TestableSaga<ReplyingSaga, ReplyingSagaData>();
+            // the Originator value is populated by the header value, not the context property
+            await saga.Handle(new StartSagaMessage() { CorrelationProperty = Guid.NewGuid() }, messageHeaders: new Dictionary<string, string>()
+            {
+                {Headers.ReplyToAddress, originatorAddress}
+            });
+            var result = await saga.HandleQueuedMessage();
+
+            var reply = result.Context.RepliedMessages.SingleOrDefault();
+            Assert.NotNull(reply);
+            Assert.AreEqual(originatorAddress, reply.Options.GetDestination());
+            Assert.AreEqual(originatorAddress, reply.Message<ReplyMessage>().OriginatorAddress);
+        }
+
+        [Test]
+        public async Task OriginatorShouldBeSetByDefault()
+        {
+            // ensure the testing API also works without explicitly defining a replyTo header value
+            var saga = new TestableSaga<ReplyingSaga, ReplyingSagaData>();
+
+            await saga.Handle(new StartSagaMessage() { CorrelationProperty = Guid.NewGuid() });
+            var result = await saga.HandleQueuedMessage();
+
+            var reply = result.Context.RepliedMessages.SingleOrDefault();
+            Assert.NotNull(reply);
+            string replyAddress = reply.Options.GetDestination();
+            Assert.NotNull(replyAddress);
+            Assert.AreEqual(replyAddress, reply.Message<ReplyMessage>().OriginatorAddress);
+        }
+
+        class ReplyingSaga : NServiceBus.Saga<ReplyingSagaData>, IAmStartedByMessages<StartSagaMessage>, IHandleMessages<SendReplyMessage>
+        {
+            protected override void ConfigureHowToFindSaga(SagaPropertyMapper<ReplyingSagaData> mapper) => mapper
+                .ConfigureMapping<StartSagaMessage>(m => m.CorrelationProperty)
+                .ToSaga(s => s.CorrelationProperty);
+
+            public Task Handle(StartSagaMessage message, IMessageHandlerContext context)
+            {
+                return context.SendLocal(new SendReplyMessage());
+            }
+
+            public Task Handle(SendReplyMessage message, IMessageHandlerContext context)
+            {
+                return ReplyToOriginator(context, new ReplyMessage { OriginatorAddress = Data.Originator });
+            }
+        }
+
+        class ReplyingSagaData : ContainSagaData
+        {
+            public Guid CorrelationProperty { get; set; }
+        }
+
+        class StartSagaMessage : IMessage
+        {
+            public Guid CorrelationProperty { get; set; }
+        }
+
+        class SendReplyMessage : ICommand
+        {
+            public Guid CorrelationProperty { get; set; }
+        }
+
+        class ReplyMessage : IMessage
+        {
+            public string OriginatorAddress { get; set; }
+        }
+    }
+}

src/NServiceBus.Testing/Sagas/TestableSaga.cs

@@ -213,7 +213,7 @@ async Task<HandleResult> InnerHandle(QueuedSagaMessage message, string handleMet
             {
                 await session.Open(context.Extensions, context.CancellationToken).ConfigureAwait(false);
 
-                var (data, isNew, mappedValue) = await LoadSagaData(message, session, context.Extensions, context.CancellationToken).ConfigureAwait(false);
+                var (data, isNew, mappedValue) = await LoadSagaData(message, session, context).ConfigureAwait(false);
                 saga.Entity = data;
 
                 await sagaMapper.InvokeHandlerMethod(saga, handleMethodName, message, context).ConfigureAwait(false);
@@ -279,16 +279,14 @@ async Task<HandleResult> HandleTimeout(OutgoingMessage<object, SendOptions> time
         }
 
         async Task<(TSagaData Data, bool IsNew, object MappedValue)> LoadSagaData(
-            QueuedSagaMessage message, ISynchronizedStorageSession session, ContextBag contextBag, CancellationToken cancellationToken)
+            QueuedSagaMessage message, ISynchronizedStorageSession session, TestableMessageHandlerContext context)
         {
             var messageMetadata = sagaMapper.GetMessageMetadata(message.Type);
             TSagaData sagaData;
 
-            if (message.Headers != null &&
-                message.Headers.TryGetValue(Headers.SagaId, out var sagaIdString) &&
-                Guid.TryParse(sagaIdString, out Guid sagaId))
+            if (message.Headers.TryGetValue(Headers.SagaId, out var sagaIdString) && Guid.TryParse(sagaIdString, out Guid sagaId))
             {
-                sagaData = await persister.Get<TSagaData>(sagaId, session, contextBag, cancellationToken).ConfigureAwait(false);
+                sagaData = await persister.Get<TSagaData>(sagaId, session, context.Extensions, context.CancellationToken).ConfigureAwait(false);
                 if (sagaData != null)
                 {
                     return (sagaData, false, null);
@@ -297,7 +295,7 @@ async Task<HandleResult> HandleTimeout(OutgoingMessage<object, SendOptions> time
 
             var messageMappedValue = sagaMapper.GetMessageMappedValue(message);
 
-            sagaData = await persister.Get<TSagaData>(sagaMapper.CorrelationPropertyName, messageMappedValue, session, contextBag, cancellationToken).ConfigureAwait(false);
+            sagaData = await persister.Get<TSagaData>(sagaMapper.CorrelationPropertyName, messageMappedValue, session, context.Extensions, context.CancellationToken).ConfigureAwait(false);
 
             if (sagaData != null)
             {
@@ -306,7 +304,10 @@ async Task<HandleResult> HandleTimeout(OutgoingMessage<object, SendOptions> time
 
             if (messageMetadata.IsAllowedToStartSaga)
             {
-                sagaData = new TSagaData { Id = Guid.NewGuid() };
+                var originatorAddress = message.Headers.TryGetValue(Headers.ReplyToAddress, out var replyAddress)
+                    ? replyAddress
+                    : context.ReplyToAddress; // This property has a default value set even when the header isn't set to require less setup for testing
+                sagaData = new TSagaData { Id = Guid.NewGuid(), Originator = originatorAddress };
                 sagaMapper.SetCorrelationPropertyValue(sagaData, messageMappedValue);
                 return (sagaData, true, messageMappedValue);
             }