Fix ref struct scan for sagas

src/NServiceBus.AcceptanceTests/Core/Conventions/When_scanning_an_assembly_containing_a_ref_struct_and_sagas_enabled.cs

@@ -0,0 +1,53 @@
+namespace NServiceBus.AcceptanceTests.Core.Conventions;
+
+using System;
+using System.Threading.Tasks;
+using AcceptanceTesting;
+using EndpointTemplates;
+using NServiceBus.AcceptanceTesting.Customization;
+using NUnit.Framework;
+
+public class When_scanning_an_assembly_containing_a_ref_struct_and_sagas_enabled : NServiceBusAcceptanceTest
+{
+ [Test]
+ public void It_should_not_throw_an_exception()
+ => Assert.DoesNotThrowAsync(
+ () => Scenario.Define<ScenarioContext>()
+ .WithEndpoint<EndpointWithASaga>()
+ .Run()
+ );
+
+ // HINT: This will get picked up by the AssemblyRouteSource created by the routing call below
+ // Even though it is not a message type, it is still checked by passing it to conventions.
+ // The conventions added by Sagas were throwing an exception when passed a ref struct.
+ // See https://github.com/Particular/NServiceBus/issues/7179 for details.
+ ref struct RefStruct { }
+
+ class EndpointWithASaga : EndpointConfigurationBuilder
+ {
+ public EndpointWithASaga() => EndpointSetup<DefaultServer>(cfg => cfg
+ .ConfigureRouting()
+ .RouteToEndpoint(
+ typeof(RefStruct).Assembly,
+ Conventions.EndpointNamingConvention(typeof(EndpointWithASaga))
+ )
+ );
+
+ class RealSagaToSetUpConventions : Saga<RealSagaToSetUpConventions.RealSagaToSetUpConventionsSagaData>, IAmStartedByMessages<SomeMessage>
+ {
+ public Task Handle(SomeMessage message, IMessageHandlerContext context) => Task.CompletedTask;
+ protected override void ConfigureHowToFindSaga(SagaPropertyMapper<RealSagaToSetUpConventionsSagaData> mapper)
+ => mapper.MapSaga(saga => saga.BusinessId).ToMessage<SomeMessage>(msg => msg.BusinessId);
+
+ public class RealSagaToSetUpConventionsSagaData : ContainSagaData
+ {
+ public virtual Guid BusinessId { get; set; }
+ }
+ }
+ }
+
+ public class SomeMessage : IMessage
+ {
+ public Guid BusinessId { get; set; }
+ }
+}

src/NServiceBus.Core/Sagas/Sagas.cs

@@ -104,6 +104,13 @@ static bool IsCompatible(Type t, Type source)
 
  static bool IsTypeATimeoutHandledByAnySaga(Type type, IEnumerable<Type> sagas)
  {
+ // MakeGenericType() throws an exception if passed a ref struct type
+ // Messages cannot be ref struct types
+ if (type.IsByRefLike)
+ {
+ return false;
+ }
+
  var timeoutHandler = typeof(IHandleTimeouts<>).MakeGenericType(type);
  var messageHandler = typeof(IHandleMessages<>).MakeGenericType(type);