Add new test to AkkaSerializationSpec. Failed for HyperionSerializer.

[seriousbox]

An error occurred while serializing the ActorPath collection with duplicate paths. For the last ActorPath, Hyperion.ValueSerializers.ObjectSerializer is used instead of Hyperion.ValueSerializers.FromSurrogateSerializer. This causes the error System.InvalidCastException: Unable to cast object of type 'Surrogate' to type 'Akka.Actor.ActorPath'. For the Poco (ISurrogated) collection of objects no error occurs regardless of the stored values.

In the test I gave an example with a simple array of elements, but in a real task the following class State is used.

public class Scheduled
{
    public Scheduled(string scheduleId, ActorPath executor)
    {
        ScheduleId = scheduleId;
        Executor = executor;
    }

    public string ScheduleId { get; }
    public ActorPath Executor { get; }
}

public sealed class State
{
    private readonly ImmutableDictionary<string, Scheduled> _entries;

    public State()
    {
        _entries = ImmutableDictionary<string, ScheduledTest>.Empty;
    }

    public State(IEnumerable<Scheduled> entries)
    {
        _entries = ImmutableDictionary.CreateRange(entries.Select(e => new KeyValuePair<string, Scheduled>(e.ScheduleId, e)));
    }

    public IEnumerable<Scheduled> Entries => _entries.Values;
}

[Aaronontheweb]

hi @seriousbox - @eaba is looking into this now

[eaba]

The root of this issue can be found in Hyperion:

if (session.Serializer.Options.PreserveObjectReferences && session.TryGetObjectId(value, out existingId))
                {
                    //write the serializer manifest
                    ObjectReferenceSerializer.Instance.WriteManifest(stream, session);
                    //write the object reference id
                    ObjectReferenceSerializer.Instance.WriteValue(stream, existingId, session);
                }

It just return the object as it was written:

public override object ReadValue(Stream stream, DeserializerSession session)
        {
            var id = stream.ReadInt32(session);
            var obj = session.GetDeserializedObject(id);
            return obj;
        }

@Aaronontheweb can't ObjectReferenceSerializer hold the Manifest of the actual Serializer?
One way to avoid this issue is to turn off PreserveObjectReferences

[eaba]

How can ObjectReferenceSerializer be improved to hold the Manifest of the actual Serializer for the object without any breaking changes? Suggestion are welcomed

[Arkatufus]

After reviewing the code, I've found several bugs that complicates this issue, each one caused by problems in the Hyperion code base. I'm moving this to the Hyperion repo instead.

[Arkatufus]

@eaba please look at akkadotnet/Hyperion#200 and akkadotnet/Hyperion#201

[eaba]

@Arkatufus okay