From ff5ffb2832b2297502d1ff44efb2e16c57a648b7 Mon Sep 17 00:00:00 2001
From: James Newton-King <james@newtonking.com>
Date: Fri, 1 Jan 2021 19:25:57 +1300
Subject: [PATCH] Copy annotations when cloning elements (#2442)

---
 .../Linq/AnnotationsTests.cs                  | 51 +++++++++++++++++++
 Src/Newtonsoft.Json/Linq/JContainer.cs        |  2 +
 Src/Newtonsoft.Json/Linq/JToken.cs            | 12 +++++
 Src/Newtonsoft.Json/Linq/JValue.cs            |  1 +
 4 files changed, 66 insertions(+)

diff --git a/Src/Newtonsoft.Json.Tests/Linq/AnnotationsTests.cs b/Src/Newtonsoft.Json.Tests/Linq/AnnotationsTests.cs
index ff3657dc..28af8376 100644
--- a/Src/Newtonsoft.Json.Tests/Linq/AnnotationsTests.cs
+++ b/Src/Newtonsoft.Json.Tests/Linq/AnnotationsTests.cs
@@ -257,6 +257,57 @@ namespace Newtonsoft.Json.Tests.Linq
             Assert.AreEqual(new Uri("http://www.google.com/"), i);
         }
 
+        [Test]
+        public void AnnotationsAreCopied()
+        {
+            JObject o = new JObject();
+            o.AddAnnotation("string!");
+            AssertCloneCopy(o, "string!");
+
+            JProperty p = new JProperty("Name", "Content");
+            p.AddAnnotation("string!");
+            AssertCloneCopy(p, "string!");
+
+            JArray a = new JArray();
+            a.AddAnnotation("string!");
+            AssertCloneCopy(a, "string!");
+
+            JConstructor c = new JConstructor("Test");
+            c.AddAnnotation("string!");
+            AssertCloneCopy(c, "string!");
+
+            JValue v = new JValue(true);
+            v.AddAnnotation("string!");
+            AssertCloneCopy(v, "string!");
+
+            JRaw r = new JRaw("raw");
+            r.AddAnnotation("string!");
+            AssertCloneCopy(r, "string!");
+        }
+
+        [Test]
+        public void MultipleAnnotationsAreCopied()
+        {
+            Version version = new Version(1, 2, 3, 4);
+
+            JObject o = new JObject();
+            o.AddAnnotation("string!");
+            o.AddAnnotation(version);
+
+            JObject o2 = (JObject)o.DeepClone();
+            Assert.AreEqual("string!", o2.Annotation<string>());
+            Assert.AreEqual(version, o2.Annotation<Version>());
+
+            o2.RemoveAnnotations<Version>();
+            Assert.AreEqual(1, o.Annotations<Version>().Count());
+            Assert.AreEqual(0, o2.Annotations<Version>().Count());
+        }
+
+        private void AssertCloneCopy<T>(JToken t, T annotation) where T : class
+        {
+            Assert.AreEqual(annotation, t.DeepClone().Annotation<T>());
+        }
+
 #if !NET20
         [Test]
         public void Example()
diff --git a/Src/Newtonsoft.Json/Linq/JContainer.cs b/Src/Newtonsoft.Json/Linq/JContainer.cs
index 6afeca6d..ac3a18a0 100644
--- a/Src/Newtonsoft.Json/Linq/JContainer.cs
+++ b/Src/Newtonsoft.Json/Linq/JContainer.cs
@@ -117,6 +117,8 @@ namespace Newtonsoft.Json.Linq
                 AddInternal(i, child, false);
                 i++;
             }
+
+            CopyAnnotations(this, other);
         }
 
         internal void CheckReentrancy()
diff --git a/Src/Newtonsoft.Json/Linq/JToken.cs b/Src/Newtonsoft.Json/Linq/JToken.cs
index 7487b9a4..8242f7f9 100644
--- a/Src/Newtonsoft.Json/Linq/JToken.cs
+++ b/Src/Newtonsoft.Json/Linq/JToken.cs
@@ -2704,5 +2704,17 @@ namespace Newtonsoft.Json.Linq
                 }
             }
         }
+
+        internal void CopyAnnotations(JToken target, JToken source)
+        {
+            if (source._annotations is object[] annotations)
+            {
+                target._annotations = annotations.ToArray();
+            }
+            else
+            {
+                target._annotations = source._annotations;
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/Src/Newtonsoft.Json/Linq/JValue.cs b/Src/Newtonsoft.Json/Linq/JValue.cs
index d39ea121..27d5de88 100644
--- a/Src/Newtonsoft.Json/Linq/JValue.cs
+++ b/Src/Newtonsoft.Json/Linq/JValue.cs
@@ -64,6 +64,7 @@ namespace Newtonsoft.Json.Linq
         public JValue(JValue other)
             : this(other.Value, other.Type)
         {
+            CopyAnnotations(this, other);
         }
 
         /// <summary>