Fix preserved reference surrogate in collection deserialization bug (#…

…264)

* Add spec

* Add preserve object reference support to surrogate deserializer

src/Hyperion.API.Tests/CoreApiSpec.ApproveApi.approved.txt

@@ -36,6 +36,7 @@ namespace Hyperion
         public object GetDeserializedObject(int id) { }
         public System.Type GetTypeFromTypeId(int typeId) { }
         public Hyperion.TypeVersionInfo GetVersionInfo([Hyperion.Internal.NotNull] System.Type type) { }
+        public void ReplaceOrAddTrackedDeserializedObject([Hyperion.Internal.NotNull] object origin, [Hyperion.Internal.NotNull] object replacement) { }
         public void TrackDeserializedObject([Hyperion.Internal.NotNull] object obj) { }
         public void TrackDeserializedType([Hyperion.Internal.NotNull] System.Type type) { }
         public void TrackDeserializedTypeWithVersion([Hyperion.Internal.NotNull] System.Type type, [Hyperion.Internal.NotNull] Hyperion.TypeVersionInfo versionInfo) { }

src/Hyperion.Akka.Integration.Tests/IntegrationSpec.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using Akka.Actor;
 using Akka.Configuration;
 using Akka.Serialization;
@@ -60,6 +61,32 @@ public void Akka_HyperionSerializer_should_serialize_properly()
             deserialized.Count.Should().Be(24);
         }
 
+        [Fact]
+        public void Bugfix263_Akka_HyperionSerializer_should_serialize_ActorPath_list()
+        {
+            var actor = Sys.ActorOf(Props.Create<MyActor>());
+            var container = new ContainerClass(new List<ActorPath>{ actor.Path, actor.Path });
+            var serialized = _serializer.ToBinary(container);
+            var deserialized = _serializer.FromBinary<ContainerClass>(serialized);
+            deserialized.Destinations.Count.Should().Be(2);
+            deserialized.Destinations[0].Should().Be(deserialized.Destinations[1]);
+        }
+
+        private class MyActor: ReceiveActor
+        {
+
+        }
+
+        private class ContainerClass
+        {
+            public ContainerClass(List<ActorPath> destinations)
+            {
+                Destinations = destinations;
+            }
+
+            public List<ActorPath> Destinations { get; }
+        }
+
         private class MyPocoClass
         {
             public string Name { get; set; }

src/Hyperion.Tests/CollectionTests.cs

@@ -15,6 +15,7 @@
 using System.Dynamic;
 using System.IO;
 using System.Linq;
+using FluentAssertions;
 using Xunit;
 using Hyperion.SerializerFactories;
 using Hyperion.ValueSerializers;
@@ -415,6 +416,35 @@ public void Issue18()
             Assert.True(msg.SequenceEqual(deserialized));
         }
 
+        [Fact]
+        public void Issue263_CanSerializeArrayOfSurrogate_WhenPreservingObjectReference()
+        {
+	        var invoked = new List<SurrogatedClass.ClassSurrogate>();
+	        var serializer = new Serializer(new SerializerOptions(
+		        preserveObjectReferences: true, 
+		        surrogates: new []
+		        {
+			        Surrogate.Create<SurrogatedClass, SurrogatedClass.ClassSurrogate>( 
+				        to => to.ToSurrogate(),
+				        from => { 
+					        invoked.Add(from);
+					        return from.FromSurrogate();
+				        }), 
+		        }));
+
+	        var objectRef = new SurrogatedClass(5);
+	        var expected = new List<SurrogatedClass> { objectRef, objectRef };
+	        using (var stream = new MemoryStream())
+	        {
+		        serializer.Serialize(expected, stream);
+		        stream.Position = 0;
+		        var deserialized = serializer.Deserialize<List<SurrogatedClass>>(stream);
+		        deserialized.Count.Should().Be(2);
+		        invoked.Count.Should().Be(1);
+		        ReferenceEquals(deserialized[0], deserialized[1]).Should().BeTrue();
+	        }
+        }
+
         #region test classes
 
         public class CustomAdd : IEnumerable<int>
@@ -451,6 +481,56 @@ public CustomAddRange(IImmutableList<int> inner)
             IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
         }
 
+        public class SurrogatedClass
+        {
+	        public class ClassSurrogate
+	        {
+		        public ClassSurrogate(string value)
+		        {
+			        Value = value;
+		        }
+
+		        public string Value { get; }
+
+		        public SurrogatedClass FromSurrogate()
+			        => new SurrogatedClass(int.Parse(Value));
+
+		        public override bool Equals(object obj)
+		        {
+			        if (ReferenceEquals(null, obj)) return false;
+			        if (ReferenceEquals(this, obj)) return true;
+			        return obj is ClassSurrogate s && s.Value == Value;
+		        }
+
+		        public override int GetHashCode()
+		        {
+			        return (Value != null ? Value.GetHashCode() : 0);
+		        }
+	        }
+
+	        public SurrogatedClass(int value)
+	        {
+		        Value = value;
+	        }
+
+	        public int Value { get; }
+
+	        public ClassSurrogate ToSurrogate()
+		        => new ClassSurrogate(Value.ToString());
+
+	        public override bool Equals(object obj)
+	        {
+		        if (ReferenceEquals(null, obj)) return false;
+		        if (ReferenceEquals(this, obj)) return true;
+		        return obj is SurrogatedClass s && s.Value == Value;
+	        }
+
+	        public override int GetHashCode()
+	        {
+		        return Value;
+	        }
+        }
+
         #endregion
 
         [Fact]

src/Hyperion/DeserializeSession.cs

@@ -65,6 +65,15 @@ public object GetDeserializedObject(int id)
             return _objectById[id];
         }
 
+        public void ReplaceOrAddTrackedDeserializedObject([NotNull] object origin, [NotNull] object replacement)
+        {
+            var index = _objectById.IndexOf(origin);
+            if (index == -1)
+                _objectById.Add(origin);
+            else
+                _objectById[index] = replacement;
+        }
+
         public void TrackDeserializedType([NotNull]Type type)
         {
             if (_identifierToType == null)

src/Hyperion/SerializerFactories/FromSurrogateSerializerFactory.cs

@@ -31,7 +31,7 @@ public override ValueSerializer BuildSerializer(Serializer serializer, Type type
             var surrogate = serializer.Options.Surrogates.FirstOrDefault(s => s.To.GetTypeInfo().IsAssignableFrom(type.GetTypeInfo()));
             var objectSerializer = new ObjectSerializer(type);
             // ReSharper disable once PossibleNullReferenceException
-            var fromSurrogateSerializer = new FromSurrogateSerializer(surrogate.FromSurrogate, objectSerializer);
+            var fromSurrogateSerializer = new FromSurrogateSerializer(surrogate.FromSurrogate, objectSerializer, serializer.Options.PreserveObjectReferences);
             typeMapping.TryAdd(type, fromSurrogateSerializer);
 
 

src/Hyperion/ValueSerializers/FromSurrogateSerializer.cs

@@ -16,11 +16,16 @@ internal sealed class FromSurrogateSerializer : ValueSerializer
     {
         private readonly ValueSerializer _surrogateSerializer;
         private readonly Func<object, object> _translator;
+        private readonly bool _preserveObjectReferences;
 
-        public FromSurrogateSerializer(Func<object, object> translator, ValueSerializer surrogateSerializer)
+        public FromSurrogateSerializer(
+            Func<object, object> translator,
+            ValueSerializer surrogateSerializer,
+            bool preserveObjectReferences)
         {
             _translator = translator;
             _surrogateSerializer = surrogateSerializer;
+            _preserveObjectReferences = preserveObjectReferences;
         }
 
         public override void WriteManifest(Stream stream, SerializerSession session)
@@ -37,6 +42,8 @@ public override object ReadValue(Stream stream, DeserializerSession session)
         {
             var surrogateValue = _surrogateSerializer.ReadValue(stream, session);
             var value = _translator(surrogateValue);
+            if(_preserveObjectReferences)
+                session.ReplaceOrAddTrackedDeserializedObject(surrogateValue, value);
             return value;
         }