Null String being reported as String rather than JTokenType.Null Jame…

…sNK/Newtonsoft.Json#2796

src/Argon/Linq/JTokenWriter.cs

@@ -215,6 +215,12 @@ public override void WriteComment(string? text)
     /// </summary>
     public override void WriteValue(string? value)
     {
+        if (value == null)
+        {
+            WriteNull();
+            return;
+        }
+
         base.WriteValue(value);
         AddJValue(new(value));
     }

src/Tests/Issues/Issue2775.cs

@@ -0,0 +1,28 @@
+    public class Issue2775
+    {
+        [Fact]
+        //https://github.com/JamesNK/Newtonsoft.Json/issues/2775
+        public void TokenType()
+        {
+            var jObject = new JObject
+            {
+                {
+                    "NullProperty", false ? "0" : null
+                }
+            };
+
+            var jToken = JToken.FromObject(jObject);
+
+            Assert.Equal(JTokenType.Null, jToken.Children().Children().Single().Type);
+
+            jObject = new()
+            {
+                {
+                    "NullProperty", (string) null
+                }
+            };
+
+            jToken = JToken.FromObject(jObject);
+            Assert.Equal(JTokenType.Null, jToken.Children().Children().Single().Type);
+        }
+    }