-Fix to preserve collection type information in certain situations when serializing

-Add missing Newtonsoft.Json.WindowsPhone.sln file

Src/Newtonsoft.Json.Tests/Serialization/JsonSerializerTest.cs

@@ -3795,11 +3795,11 @@ keyword such as type of business.""
     public void DeserializeNullableStruct()
     {
       NullableStructPropertyClass nullableStructPropertyClass = new NullableStructPropertyClass();
-      nullableStructPropertyClass.Foo1 = new StructISerializable() {Name = "foo 1"};
-      nullableStructPropertyClass.Foo2 = new StructISerializable() {Name = "foo 2"};
+      nullableStructPropertyClass.Foo1 = new StructISerializable() { Name = "foo 1" };
+      nullableStructPropertyClass.Foo2 = new StructISerializable() { Name = "foo 2" };
 
       NullableStructPropertyClass barWithNull = new NullableStructPropertyClass();
-      barWithNull.Foo1 = new StructISerializable() {Name = "foo 1"};
+      barWithNull.Foo1 = new StructISerializable() { Name = "foo 1" };
       barWithNull.Foo2 = null;
 
       //throws error on deserialization because bar1.Foo2 is of type Foo?
@@ -3827,5 +3827,63 @@ keyword such as type of business.""
         });
     }
 #endif
+
+    [Test]
+    public void SerializingIEnumerableOfTShouldRetainGenericTypeInfo()
+    {
+      CustomEnumerable<Product> products = new CustomEnumerable<Product>();
+
+      string json = JsonConvert.SerializeObject(products, Formatting.Indented, new JsonSerializerSettings { TypeNameHandling = TypeNameHandling.All });
+
+      Assert.AreEqual(@"{
+  ""$type"": ""Newtonsoft.Json.Tests.TestObjects.Product[], Newtonsoft.Json.Tests"",
+  ""$values"": []
+}", json);
+    }
+
+    public class CustomEnumerable<T> : IEnumerable<T>
+    {
+      //NOTE: a simple linked list
+      private readonly T value;
+      private readonly CustomEnumerable<T> next;
+      private readonly int count;
+
+      private CustomEnumerable(T value, CustomEnumerable<T> next)
+      {
+        this.value = value;
+        this.next = next;
+        count = this.next.count + 1;
+      }
+
+      public CustomEnumerable()
+      {
+        count = 0;
+      }
+
+      public CustomEnumerable<T> AddFirst(T newVal)
+      {
+        return new CustomEnumerable<T>(newVal, this);
+      }
+
+      public IEnumerator<T> GetEnumerator()
+      {
+        if (count == 0) // last node
+          yield break;
+        yield return value;
+
+        var nextInLine = next;
+        while (nextInLine != null)
+        {
+          if (nextInLine.count != 0)
+            yield return nextInLine.value;
+          nextInLine = nextInLine.next;
+        }
+      }
+
+      IEnumerator IEnumerable.GetEnumerator()
+      {
+        return GetEnumerator();
+      }
+    }
   }
 }

Src/Newtonsoft.Json.WindowsPhone.sln

@@ -0,0 +1,31 @@
+
+Microsoft Visual Studio Solution File, Format Version 11.00
+# Visual Studio 2010
+Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Lib", "Lib", "{F69285DD-24FB-4A60-AE8B-4C2744285D0F}"
+	ProjectSection(SolutionItems) = preProject
+		Lib\NUnit\Silverlight\nunit.framework.dll = Lib\NUnit\Silverlight\nunit.framework.dll
+	EndProjectSection
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Newtonsoft.Json.WindowsPhone", "Newtonsoft.Json\Newtonsoft.Json.WindowsPhone.csproj", "{7A7F70AB-5C07-47ED-BDD2-ECC14DBACA5E}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Newtonsoft.Json.Tests.WindowsPhone", "Newtonsoft.Json.Tests\Newtonsoft.Json.Tests.WindowsPhone.csproj", "{5ED71C8C-D0A6-487C-9A8C-BB855ECEAF75}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{7A7F70AB-5C07-47ED-BDD2-ECC14DBACA5E}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{7A7F70AB-5C07-47ED-BDD2-ECC14DBACA5E}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{7A7F70AB-5C07-47ED-BDD2-ECC14DBACA5E}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{7A7F70AB-5C07-47ED-BDD2-ECC14DBACA5E}.Release|Any CPU.Build.0 = Release|Any CPU
+		{5ED71C8C-D0A6-487C-9A8C-BB855ECEAF75}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{5ED71C8C-D0A6-487C-9A8C-BB855ECEAF75}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{5ED71C8C-D0A6-487C-9A8C-BB855ECEAF75}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{5ED71C8C-D0A6-487C-9A8C-BB855ECEAF75}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+EndGlobal

Src/Newtonsoft.Json/Serialization/JsonArrayContract.cs

@@ -77,19 +77,40 @@ namespace Newtonsoft.Json.Serialization
 
       if (_genericCollectionDefinitionType != null)
       {
-        if (_genericWrapperType == null)
-        {
-          _genericWrapperType = ReflectionUtils.MakeGenericType(typeof (CollectionWrapper<>), CollectionItemType);
-
-          ConstructorInfo genericWrapperConstructor = _genericWrapperType.GetConstructor(new[] {_genericCollectionDefinitionType});
-          _genericWrapperCreator = JsonTypeReflector.ReflectionDelegateFactory.CreateMethodCall<object>(genericWrapperConstructor);
-        }
-
+        EnsureGenericWrapperCreator();
         return (IWrappedCollection) _genericWrapperCreator(null, list);
       }
       else
       {
-        return new CollectionWrapper<object>((IList<object>)((IEnumerable)list).Cast<object>().ToList());
+        IList values = ((IEnumerable) list).Cast<object>().ToList();
+
+        if (CollectionItemType != null)
+        {
+          Array array = Array.CreateInstance(CollectionItemType, values.Count);
+          for (int i = 0; i < values.Count; i++)
+          {
+            array.SetValue(values[i], i);
+          }
+
+          values = array;
+        }
+
+        return new CollectionWrapper<object>(values);
+      }
+    }
+
+    private void EnsureGenericWrapperCreator()
+    {
+      if (_genericWrapperType == null)
+      {
+        _genericWrapperType = ReflectionUtils.MakeGenericType(typeof (CollectionWrapper<>), CollectionItemType);
+
+        Type constructorArgument = (ReflectionUtils.InheritsGenericDefinition(_genericCollectionDefinitionType, typeof (List<>)))
+                                     ? ReflectionUtils.MakeGenericType(typeof (ICollection<>), CollectionItemType)
+                                     : _genericCollectionDefinitionType;
+
+        ConstructorInfo genericWrapperConstructor = _genericWrapperType.GetConstructor(new[] { constructorArgument });
+        _genericWrapperCreator = JsonTypeReflector.ReflectionDelegateFactory.CreateMethodCall<object>(genericWrapperConstructor);
       }
     }