-Improved error message when an object is reused with PreserveReferencesHandling

Src/Newtonsoft.Json.Tests/Issues/Issue1351.cs

@@ -0,0 +1,178 @@
+#region License
+// Copyright (c) 2007 James Newton-King
+//
+// Permission is hereby granted, free of charge, to any person
+// obtaining a copy of this software and associated documentation
+// files (the "Software"), to deal in the Software without
+// restriction, including without limitation the rights to use,
+// copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the
+// Software is furnished to do so, subject to the following
+// conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+// OTHER DEALINGS IN THE SOFTWARE.
+#endregion
+
+#if !NET20
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Linq;
+using System.Runtime.Serialization;
+using System.Text;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
+using System.Xml;
+#if !NET20
+using System.Xml.Linq;
+#endif
+#if DNXCORE50
+using Xunit;
+using Test = Xunit.FactAttribute;
+using Assert = Newtonsoft.Json.Tests.XUnitAssert;
+#else
+using NUnit.Framework;
+#endif
+
+namespace Newtonsoft.Json.Tests.Issues
+{
+    [TestFixture]
+    public class Issue1351 : TestFixtureBase
+    {
+        public class Color
+        {
+            public Color()
+            {
+            }
+
+            public Color(uint colorCode)
+            {
+                A = (byte)((colorCode & 0xff000000) >> 24);
+                R = (byte)((colorCode & 0x00ff0000) >> 16);
+                G = (byte)((colorCode & 0x0000ff00) >> 8);
+                B = (byte)(colorCode & 0x000000ff);
+            }
+
+            public byte A { get; set; }
+            public byte R { get; set; }
+            public byte G { get; set; }
+            public byte B { get; set; }
+        }
+
+        public static class Colors
+        {
+            public static Color White = new Color(0xFFFFFFFF);
+        }
+
+        [DataContract]
+        public class TestClass
+        {
+            public TestClass()
+            {
+                Color = Colors.White;
+            }
+
+            [DataMember]
+            public Color Color { get; set; }
+        }
+
+        [Test]
+        public void Test()
+        {
+            var t = new List<TestClass>
+            {
+                new TestClass
+                {
+                    Color = new Color
+                    {
+                        A = 1,
+                        G = 1,
+                        B = 1,
+                        R = 1
+                    }
+                },
+                new TestClass
+                {
+                    Color = new Color
+                    {
+                        A = 2,
+                        G = 2,
+                        B = 2,
+                        R = 2
+                    }
+                }
+            };
+            var settings = new JsonSerializerSettings
+            {
+                TypeNameHandling = TypeNameHandling.Auto,
+                PreserveReferencesHandling = PreserveReferencesHandling.Objects,
+                Formatting = Formatting.Indented
+            };
+
+            var json = JsonConvert.SerializeObject(t, settings);
+
+            var exception = ExceptionAssert.Throws<JsonSerializationException>(() =>
+                {
+                    JsonConvert.DeserializeObject<List<TestClass>>(json, settings);
+                },
+                "Error reading object reference '4'. Path '[1].Color.A', line 16, position 10.");
+
+            Assert.AreEqual("A different Id has already been assigned for value 'Newtonsoft.Json.Tests.Issues.Issue1351+Color'. This error may be caused by an object being reused multiple times during deserialization and can be fixed with the setting ObjectCreationHandling.Replace.", exception.InnerException.Message);
+        }
+
+        [Test]
+        public void Test_Replace()
+        {
+            var t = new List<TestClass>
+            {
+                new TestClass
+                {
+                    Color = new Color
+                    {
+                        A = 1,
+                        G = 1,
+                        B = 1,
+                        R = 1
+                    }
+                },
+                new TestClass
+                {
+                    Color = new Color
+                    {
+                        A = 2,
+                        G = 2,
+                        B = 2,
+                        R = 2
+                    }
+                }
+            };
+            var settings = new JsonSerializerSettings
+            {
+                TypeNameHandling = TypeNameHandling.Auto,
+                PreserveReferencesHandling = PreserveReferencesHandling.Objects,
+                Formatting = Formatting.Indented,
+                ObjectCreationHandling = ObjectCreationHandling.Replace
+            };
+            var json = JsonConvert.SerializeObject(t, settings);
+
+            var obj = JsonConvert.DeserializeObject<List<TestClass>>(json, settings);
+
+            var o1 = obj[0];
+            Assert.AreEqual(1, o1.Color.A);
+
+            var o2 = obj[1];
+            Assert.AreEqual(2, o2.Color.A);
+        }
+    }
+}
+#endif

Src/Newtonsoft.Json/Serialization/JsonSerializerInternalBase.cs

@@ -74,7 +74,7 @@ namespace Newtonsoft.Json.Serialization
                         EqualityComparer<string>.Default,
                         new ReferenceEqualsEqualityComparer(),
                         "A different value already has the Id '{0}'.",
-                        "A different Id has already been assigned for value '{0}'.");
+                        "A different Id has already been assigned for value '{0}'. This error may be caused by an object being reused multiple times during deserialization and can be fixed with the setting ObjectCreationHandling.Replace.");
                 }
 
                 return _mappings;