CSHARP-1296: Add delayed lookup of child serializers to prevent stack…

… overflows when there are cyclic types.

src/MongoDB.Bson.Tests/MongoDB.Bson.Tests.csproj

@@ -139,6 +139,7 @@
     <Compile Include="Serialization\IdGenerators\AscendingGuidGeneratorTests.cs" />
     <Compile Include="Serialization\IdGenerators\CombGuidGeneratorTests.cs" />
     <Compile Include="Serialization\Options\RepresentationConverterTests.cs" />
+    <Compile Include="Serialization\Serializers\EnumerableInterfaceImplementerSerializerTests.cs" />
     <Compile Include="Serialization\Serializers\ExpandoObjectSerializerTests.cs" />
     <Compile Include="Serialization\Serializers\ExtraElementsTests.cs" />
     <Compile Include="Serialization\Serializers\KeyValuePairSerializerTests.cs" />

src/MongoDB.Bson.Tests/Serialization/Serializers/EnumerableInterfaceImplementerSerializerTests.cs

@@ -0,0 +1,83 @@
+/* Copyright 2015 MongoDB Inc.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+using System.Collections;
+using System.Collections.Generic;
+using System.IO;
+using FluentAssertions;
+using MongoDB.Bson.IO;
+using MongoDB.Bson.Serialization;
+using MongoDB.Bson.Serialization.Serializers;
+using NUnit.Framework;
+
+namespace MongoDB.Bson.Tests.Serialization.Serializers
+{
+    [TestFixture]
+    public class EnumerableInterfaceImplementerSerializerTests
+    {
+        public class C : IEnumerable<C>
+        {
+            public int Id;
+            public List<C> Children;
+
+            public IEnumerator<C> GetEnumerator()
+            {
+                return Children.GetEnumerator();
+            }
+
+            IEnumerator IEnumerable.GetEnumerator()
+            {
+                return GetEnumerator();
+            }
+        }
+
+        [Test]
+        public void LookupSerializer_should_not_throw_StackOverflowException()
+        {
+            var serializer = BsonSerializer.LookupSerializer<C>();
+
+            serializer.Should().BeOfType<EnumerableInterfaceImplementerSerializer<C, C>>();
+            var itemSerializer = ((EnumerableInterfaceImplementerSerializer<C, C>)serializer).ItemSerializer;
+            itemSerializer.Should().BeSameAs(serializer);
+        }
+
+        [Test]
+        public void Serialize_should_return_expected_result()
+        {
+            var subject = CreateSubject();
+
+            using (var stringWriter = new StringWriter())
+            using (var jsonWriter = new JsonWriter(stringWriter))
+            {
+                var context = BsonSerializationContext.CreateRoot(jsonWriter);
+                var value = new C { Id = 1, Children = new List<C> { new C { Id = 2, Children = new List<C>() } } };
+
+                subject.Serialize(context, value);
+
+                var json = stringWriter.ToString();
+                json.Should().Be("[[]]");
+            }
+        }
+
+        private IBsonSerializer<C> CreateSubject()
+        {
+            // create subject without using the global serializer registry
+            var serializerRegistry = new BsonSerializerRegistry();
+            var subject = new EnumerableInterfaceImplementerSerializer<C, C>(serializerRegistry);
+            serializerRegistry.RegisterSerializer(typeof(C), subject);
+            return subject;
+        }
+    }
+}

src/MongoDB.Bson/Serialization/AttributedSerializationProvider.cs

@@ -1,4 +1,4 @@
-/* Copyright 2010-2014 MongoDB Inc.
+/* Copyright 2010-2015 MongoDB Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
@@ -23,14 +23,8 @@ namespace MongoDB.Bson.Serialization
     /// </summary>
     public class AttributedSerializationProvider : BsonSerializationProviderBase
     {
-        /// <summary>
-        /// Gets a serializer for a type that has been annotated with a <see cref="BsonSerializerAttribute"/> specifying which serializer to use.
-        /// </summary>
-        /// <param name="type">The type.</param>
-        /// <returns>
-        /// A serializer.
-        /// </returns>
-        public override IBsonSerializer GetSerializer(Type type)
+        /// <inheritdoc/>
+        public override IBsonSerializer GetSerializer(Type type, IBsonSerializerRegistry serializerRegistry)
         {
             if (type == null)
             {

src/MongoDB.Bson/Serialization/BsonClassMapSerializationProvider.cs

@@ -1,4 +1,4 @@
-/* Copyright 2010-2014 MongoDB Inc.
+/* Copyright 2010-2015 MongoDB Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
@@ -20,14 +20,10 @@ namespace MongoDB.Bson.Serialization
     /// <summary>
     /// Represents the class map serialization provider.
     /// </summary>
-    internal class BsonClassMapSerializationProvider : IBsonSerializationProvider
+    internal class BsonClassMapSerializationProvider : BsonSerializationProviderBase
     {
-        /// <summary>
-        /// Gets the serializer for a type.
-        /// </summary>
-        /// <param name="type">The type.</param>
-        /// <returns>The serializer.</returns>
-        public IBsonSerializer GetSerializer(Type type)
+        /// <inheritdoc/>
+        public override IBsonSerializer GetSerializer(Type type, IBsonSerializerRegistry serializerRegistry)
         {
             if (type == null)
             {

src/MongoDB.Bson/Serialization/BsonObjectModelSerializationProvider.cs

@@ -1,4 +1,4 @@
-/* Copyright 2010-2014 MongoDB Inc.
+/* Copyright 2010-2015 MongoDB Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
@@ -22,7 +22,7 @@ namespace MongoDB.Bson.Serialization
     /// <summary>
     /// Provides serializers for BsonValue and its derivations.
     /// </summary>
-    public class BsonObjectModelSerializationProvider : IBsonSerializationProvider
+    public class BsonObjectModelSerializationProvider : BsonSerializationProviderBase
     {
         private static readonly Dictionary<Type, IBsonSerializer> __serializers;
 
@@ -54,14 +54,8 @@ static BsonObjectModelSerializationProvider()
             };
         }
 
-        /// <summary>
-        /// Gets a serializer for a type.
-        /// </summary>
-        /// <param name="type">The type.</param>
-        /// <returns>
-        /// A serializer.
-        /// </returns>
-        public IBsonSerializer GetSerializer(Type type)
+        /// <inheritdoc/>
+        public override IBsonSerializer GetSerializer(Type type, IBsonSerializerRegistry serializerRegistry)
         {
             if (type == null)
             {

src/MongoDB.Bson/Serialization/BsonSerializationProviderBase.cs

@@ -1,4 +1,4 @@
-/* Copyright 2010-2014 MongoDB Inc.
+/* Copyright 2010-2015 MongoDB Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
@@ -20,16 +20,16 @@ namespace MongoDB.Bson.Serialization
     /// <summary>
     /// Base class for serialization providers.
     /// </summary>
-    public abstract class BsonSerializationProviderBase : IBsonSerializationProvider
+    public abstract class BsonSerializationProviderBase : IRegistryAwareBsonSerializationProvider
     {
-        /// <summary>
-        /// Gets a serializer for a type.
-        /// </summary>
-        /// <param name="type">The type.</param>
-        /// <returns>
-        /// A serializer.
-        /// </returns>
-        public abstract IBsonSerializer GetSerializer(Type type);
+        /// <inheritdoc/>
+        public virtual IBsonSerializer GetSerializer(Type type)
+        {
+            return GetSerializer(type, BsonSerializer.SerializerRegistry);
+        }
+
+        /// <inheritdoc/>
+        public abstract IBsonSerializer GetSerializer(Type type, IBsonSerializerRegistry serializerRegistry);
 
         /// <summary>
         /// Creates the serializer from a serializer type definition and type arguments.
@@ -38,9 +38,23 @@ public abstract class BsonSerializationProviderBase : IBsonSerializationProvider
         /// <param name="typeArguments">The type arguments.</param>
         /// <returns>A serializer.</returns>
         protected virtual IBsonSerializer CreateGenericSerializer(Type serializerTypeDefinition, params Type[] typeArguments)
+        {
+            return CreateGenericSerializer(serializerTypeDefinition, typeArguments, BsonSerializer.SerializerRegistry);
+        }
+
+        /// <summary>
+        /// Creates the serializer from a serializer type definition and type arguments.
+        /// </summary>
+        /// <param name="serializerTypeDefinition">The serializer type definition.</param>
+        /// <param name="typeArguments">The type arguments.</param>
+        /// <param name="serializerRegistry">The serializer registry.</param>
+        /// <returns>
+        /// A serializer.
+        /// </returns>
+        protected virtual IBsonSerializer CreateGenericSerializer(Type serializerTypeDefinition, Type[] typeArguments, IBsonSerializerRegistry serializerRegistry)
         {
             var serializerType = serializerTypeDefinition.MakeGenericType(typeArguments);
-            return CreateSerializer(serializerType);
+            return CreateSerializer(serializerType, serializerRegistry);
         }
 
         /// <summary>
@@ -50,7 +64,34 @@ protected virtual IBsonSerializer CreateGenericSerializer(Type serializerTypeDef
         /// <returns>A serializer.</returns>
         protected virtual IBsonSerializer CreateSerializer(Type serializerType)
         {
-            return (IBsonSerializer)Activator.CreateInstance(serializerType);
+            return CreateSerializer(serializerType, BsonSerializer.SerializerRegistry);
+        }
+
+        /// <summary>
+        /// Creates the serializer.
+        /// </summary>
+        /// <param name="serializerType">The serializer type.</param>
+        /// <param name="serializerRegistry">The serializer registry.</param>
+        /// <returns>
+        /// A serializer.
+        /// </returns>
+        protected virtual IBsonSerializer CreateSerializer(Type serializerType, IBsonSerializerRegistry serializerRegistry)
+        {
+            var constructorInfo = serializerType.GetConstructor(new[] { typeof(IBsonSerializerRegistry) });
+            if (constructorInfo != null)
+            {
+                return (IBsonSerializer)constructorInfo.Invoke(new object[] { serializerRegistry });
+            }
+
+            constructorInfo = serializerType.GetConstructor(new Type[0]);
+            if (constructorInfo != null)
+            {
+                return (IBsonSerializer)constructorInfo.Invoke(new object[0]);
+            }
+
+            throw new MissingMethodException(string.Format(
+                "No suitable constructor found for serializer type: '{0}'.",
+                serializerType.FullName));
         }
     }
 }

src/MongoDB.Bson/Serialization/BsonSerializerRegistry.cs

@@ -1,4 +1,4 @@
-/* Copyright 2010-2014 MongoDB Inc.
+/* Copyright 2010-2015 MongoDB Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
@@ -125,7 +125,18 @@ private IBsonSerializer CreateSerializer(Type type)
         {
             foreach (var serializationProvider in _serializationProviders)
             {
-                var serializer = serializationProvider.GetSerializer(type);
+                IBsonSerializer serializer;
+
+                var registryAwareSerializationProvider = serializationProvider as IRegistryAwareBsonSerializationProvider;
+                if (registryAwareSerializationProvider != null)
+                {
+                    serializer = registryAwareSerializationProvider.GetSerializer(type, this);
+                }
+                else
+                {
+                    serializer = serializationProvider.GetSerializer(type);
+                }
+
                 if (serializer != null)
                 {
                     return serializer;