-Added support for deserializing to readonly collections and dictionaries on classes with non-default constructors

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

@@ -4441,5 +4441,75 @@ keyword such as type of business.""
   ""newMemberWithProperty"": null
 }", result);
     }
+
+    public class NonDefaultConstructorWithReadOnlyCollectionProperty
+    {
+      public string Title { get; set; }
+      public IList<string> Categories { get; private set; }
+
+      public NonDefaultConstructorWithReadOnlyCollectionProperty(string title)
+      {
+        Title = title;
+        Categories = new List<string>();
+      }
+    }
+
+    [Test]
+    public void NonDefaultConstructorWithReadOnlyCollectionPropertyTest()
+    {
+      NonDefaultConstructorWithReadOnlyCollectionProperty c1 = new NonDefaultConstructorWithReadOnlyCollectionProperty("blah");
+      c1.Categories.Add("one");
+      c1.Categories.Add("two");
+
+      string json = JsonConvert.SerializeObject(c1, Formatting.Indented);
+      Assert.AreEqual(@"{
+  ""Title"": ""blah"",
+  ""Categories"": [
+    ""one"",
+    ""two""
+  ]
+}", json);
+
+      NonDefaultConstructorWithReadOnlyCollectionProperty c2 = JsonConvert.DeserializeObject<NonDefaultConstructorWithReadOnlyCollectionProperty>(json);
+      Assert.AreEqual(c1.Title, c2.Title);
+      Assert.AreEqual(c1.Categories.Count, c2.Categories.Count);
+      Assert.AreEqual("one", c2.Categories[0]);
+      Assert.AreEqual("two", c2.Categories[1]);
+    }
+
+    public class NonDefaultConstructorWithReadOnlyDictionaryProperty
+    {
+      public string Title { get; set; }
+      public IDictionary<string, int> Categories { get; private set; }
+
+      public NonDefaultConstructorWithReadOnlyDictionaryProperty(string title)
+      {
+        Title = title;
+        Categories = new Dictionary<string, int>();
+      }
+    }
+
+    [Test]
+    public void NonDefaultConstructorWithReadOnlyDictionaryPropertyTest()
+    {
+      NonDefaultConstructorWithReadOnlyDictionaryProperty c1 = new NonDefaultConstructorWithReadOnlyDictionaryProperty("blah");
+      c1.Categories.Add("one", 1);
+      c1.Categories.Add("two", 2);
+
+      string json = JsonConvert.SerializeObject(c1, Formatting.Indented);
+      Assert.AreEqual(@"{
+  ""Title"": ""blah"",
+  ""Categories"": {
+    ""one"": 1,
+    ""two"": 2
+  }
+}", json);
+
+      NonDefaultConstructorWithReadOnlyDictionaryProperty c2 = JsonConvert.DeserializeObject<NonDefaultConstructorWithReadOnlyDictionaryProperty>(json);
+      Assert.AreEqual(c1.Title, c2.Title);
+      Assert.AreEqual(c1.Categories.Count, c2.Categories.Count);
+      Assert.AreEqual(1, c2.Categories["one"]);
+      Assert.AreEqual(2, c2.Categories["two"]);
+    }
   }
 }

Src/Newtonsoft.Json/Serialization/JsonSerializerInternalReader.cs

@@ -915,7 +915,47 @@ namespace Newtonsoft.Json.Serialization
         object value = remainingPropertyValue.Value;
 
         if (ShouldSetPropertyValue(remainingPropertyValue.Key, remainingPropertyValue.Value))
+        {
           property.ValueProvider.SetValue(createdObject, value);
+        }
+        else if (!property.Writable && value != null)
+        {
+          // handle readonly collection/dictionary properties
+          JsonContract propertyContract = Serializer.ContractResolver.ResolveContract(property.PropertyType);
+
+          if (propertyContract is JsonArrayContract)
+          {
+            JsonArrayContract propertyArrayContract = propertyContract as JsonArrayContract;
+
+            object createdObjectCollection = property.ValueProvider.GetValue(createdObject);
+            if (createdObjectCollection != null)
+            {
+              IWrappedCollection createdObjectCollectionWrapper = propertyArrayContract.CreateWrapper(createdObjectCollection);
+              IWrappedCollection newValues = propertyArrayContract.CreateWrapper(value);
+
+              foreach (object newValue in newValues)
+              {
+                createdObjectCollectionWrapper.Add(newValue);
+              }
+            }
+          }
+          else if (propertyContract is JsonDictionaryContract)
+          {
+            JsonDictionaryContract jsonDictionaryContract = propertyContract as JsonDictionaryContract;
+
+            object createdObjectDictionary = property.ValueProvider.GetValue(createdObject);
+            if (createdObjectDictionary != null)
+            {
+              IWrappedDictionary createdObjectDictionaryWrapper = jsonDictionaryContract.CreateWrapper(createdObjectDictionary);
+              IWrappedDictionary newValues = jsonDictionaryContract.CreateWrapper(value);
+
+              foreach (DictionaryEntry newValue in newValues)
+              {
+                createdObjectDictionaryWrapper.Add(newValue.Key, newValue.Value);
+              }
+            }
+          }
+        }
       }
 
       contract.InvokeOnDeserialized(createdObject, Serializer.Context);