-Added covariance to IJEnumerable type parameter

-Fixed inaccessible private getter/setters on base classes

Src/Newtonsoft.Json.Tests/Linq/LinqToJsonTest.cs

@@ -698,6 +698,21 @@ keyword such as type of business.""
       Assert.AreEqual(new DateTime(2000, 10, 15, 5, 5, 5, DateTimeKind.Utc), d);
     }
 
+#if !(NET20 || NET35 || SILVERLIGHT)
+    [Test]
+    public void CovariantIJEnumerable()
+    {
+      IEnumerable<JObject> o = new[]
+        {
+          JObject.FromObject(new {First = 1, Second = 2}),
+          JObject.FromObject(new {First = 1, Second = 2})
+        };
+
+      IJEnumerable<JToken> values = o.Properties();
+      Assert.AreEqual(4, values.Count());
+    }
+#endif
+
     [Test]
     public void ChildrenExtension()
     {

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

@@ -3697,5 +3697,54 @@ keyword such as type of business.""
       Assert.AreEqual(2, obj.Position.Y);
       Assert.AreEqual(3, obj.Position.Z);
     }
+
+    [JsonObject(MemberSerialization.OptIn)]
+    public class Derived : Base
+    {
+      [JsonProperty]
+      public string IDoWork { get; private set; }
+
+      private Derived() { }
+
+      internal Derived(string dontWork, string doWork)
+        : base(dontWork)
+      {
+        IDoWork = doWork;
+      }
+    }
+
+    [JsonObject(MemberSerialization.OptIn)]
+    public class Base
+    {
+      [JsonProperty]
+      public string IDontWork { get; private set; }
+
+      protected Base() { }
+
+      internal Base(string dontWork)
+      {
+        IDontWork = dontWork;
+      }
+    }
+
+    [Test]
+    public void PrivateSetterOnBaseClassProperty()
+    {
+      var derived = new Derived("meh", "woo");
+
+      var settings = new JsonSerializerSettings
+      {
+        TypeNameHandling = TypeNameHandling.Objects,
+        ConstructorHandling = ConstructorHandling.AllowNonPublicDefaultConstructor
+      };
+
+      string json = JsonConvert.SerializeObject(derived, Formatting.Indented, settings);
+
+      var meh = JsonConvert.DeserializeObject<Base>(json, settings);
+
+      Assert.AreEqual(((Derived)meh).IDoWork, "woo");
+      Assert.AreEqual(meh.IDontWork, "meh");
+    }
+
   }
 }

Src/Newtonsoft.Json/Linq/IJEnumerable.cs

@@ -9,7 +9,11 @@ namespace Newtonsoft.Json.Linq
   /// Represents a collection of <see cref="JToken"/> objects.
   /// </summary>
   /// <typeparam name="T">The type of token</typeparam>
-  public interface IJEnumerable<T> : IEnumerable<T> where T : JToken
+  public interface IJEnumerable<
+#if !(NET20 || NET35 || SILVERLIGHT)
+    out
+#endif
+    T> : IEnumerable<T> where T : JToken
   {
     /// <summary>
     /// Gets the <see cref="IJEnumerable{JToken}"/> with the specified key.

Src/Newtonsoft.Json/Utilities/ReflectionUtils.cs

@@ -880,10 +880,21 @@ namespace Newtonsoft.Json.Utilities
     {
       ValidationUtils.ArgumentNotNull(targetType, "targetType");
 
-      List<MemberInfo> propertyInfos = new List<MemberInfo>(targetType.GetProperties(bindingAttr));
+      List<PropertyInfo> propertyInfos = new List<PropertyInfo>(targetType.GetProperties(bindingAttr));
       GetChildPrivateProperties(propertyInfos, targetType, bindingAttr);
 
-      return propertyInfos.Cast<PropertyInfo>();
+      // a base class private getter/setter will be inaccessable unless the property was gotten from the base class
+      for (int i = 0; i < propertyInfos.Count; i++)
+      {
+        PropertyInfo member = propertyInfos[i];
+        if (member.DeclaringType != targetType)
+        {
+          PropertyInfo declaredMember = member.DeclaringType.GetProperty(member.Name, bindingAttr);
+          propertyInfos[i] = declaredMember;
+        }
+      }
+
+      return propertyInfos;
     }
 
     public static BindingFlags RemoveFlag(this BindingFlags bindingAttr, BindingFlags flag)
@@ -893,7 +904,7 @@ namespace Newtonsoft.Json.Utilities
         : bindingAttr;
     }
 
-    private static void GetChildPrivateProperties(IList<MemberInfo> initialProperties, Type targetType, BindingFlags bindingAttr)
+    private static void GetChildPrivateProperties(IList<PropertyInfo> initialProperties, Type targetType, BindingFlags bindingAttr)
     {
       // fix weirdness with private PropertyInfos only being returned for the current Type
       // find base type properties and add them to result