Resolve scoped TypeAttr

Author: mythz

src/ServiceStack.Text/Common/DeserializeTypeRefJson.cs

@@ -8,8 +8,6 @@ internal static class DeserializeTypeRefJson
     {
         private static readonly JsonTypeSerializer Serializer = (JsonTypeSerializer)JsonTypeSerializer.Instance;
 
-        static readonly ReadOnlyMemory<char> typeAttr = JsWriter.TypeAttr.AsMemory();
-
         internal static object StringToType(ReadOnlySpan<char> strType,
             TypeConfig typeConfig,
             EmptyCtorDelegate ctorFn,
@@ -34,6 +32,7 @@ internal static object StringToType(ReadOnlySpan<char> strType,
                 return ctorFn();
 
             var config = JsConfig.GetConfig();
+            var typeAttr = config.TypeAttrMemory;
 
             object instance = null;
             var lenient = config.PropertyConvention == PropertyConvention.Lenient;

src/ServiceStack.Text/JsConfig.cs

@@ -406,21 +406,17 @@ public static string TypeAttr
             {
                 var config = Config.AssertNotInit();
                 config.TypeAttr = value;
-                config.JsonTypeAttrInObject = JsonTypeSerializer.GetTypeAttrInObject(value);
-                config.JsvTypeAttrInObject = JsvTypeSerializer.GetTypeAttrInObject(value);
             }
         }
 
         internal static string JsonTypeAttrInObject
         {
             get => JsConfigScope.Current != null ? JsConfigScope.Current.JsonTypeAttrInObject : Config.Instance.JsonTypeAttrInObject;
-            set => Config.AssertNotInit().JsonTypeAttrInObject = value;
         }
 
         internal static string JsvTypeAttrInObject
         {
             get => JsConfigScope.Current != null ? JsConfigScope.Current.JsvTypeAttrInObject : Config.Instance.JsvTypeAttrInObject;
-            set => Config.AssertNotInit().JsvTypeAttrInObject = value;
         }
 
         public static Func<Type, string> TypeWriter

src/ServiceStack.Text/JsConfigScope.cs

@@ -120,10 +120,27 @@ private Config(Config config)
         public bool TreatEnumAsInteger { get; set; }
         public bool ExcludeTypeInfo { get; set; }
         public bool IncludeTypeInfo { get; set; }
-        public string TypeAttr { get; set; }
+
+        private string typeAttr;
+        public string TypeAttr
+        {
+            get => typeAttr;
+            set
+            {
+                typeAttrSpan = null;
+                jsonTypeAttrInObject = null;
+                jsvTypeAttrInObject = null;
+                typeAttr = value;
+            }
+        }
+        ReadOnlyMemory<char>? typeAttrSpan = null;
+        public ReadOnlyMemory<char> TypeAttrMemory => typeAttrSpan ??= TypeAttr.AsMemory(); 
         public string DateTimeFormat { get; set; }
-        internal string JsonTypeAttrInObject { get; set; }
-        internal string JsvTypeAttrInObject { get; set; }
+        private string jsonTypeAttrInObject;
+        internal string JsonTypeAttrInObject => jsonTypeAttrInObject ??= JsonTypeSerializer.GetTypeAttrInObject(TypeAttr);
+        private string jsvTypeAttrInObject;
+        internal string JsvTypeAttrInObject => jsvTypeAttrInObject ??= JsvTypeSerializer.GetTypeAttrInObject(TypeAttr);
+        
         public Func<Type, string> TypeWriter { get; set; }
         public Func<string, Type> TypeFinder { get; set; }
         public Func<string, object> ParsePrimitiveFn { get; set; }
@@ -180,8 +197,6 @@ public bool EmitLowercaseUnderscoreNames
             IncludeTypeInfo = false,
             TypeAttr = JsWriter.TypeAttr,
             DateTimeFormat = null,
-            JsonTypeAttrInObject = JsonTypeSerializer.GetTypeAttrInObject(JsWriter.TypeAttr),
-            JsvTypeAttrInObject = JsvTypeSerializer.GetTypeAttrInObject(JsWriter.TypeAttr),
             TypeWriter = AssemblyUtils.WriteType,
             TypeFinder = AssemblyUtils.FindType,
             ParsePrimitiveFn = null,
@@ -222,8 +237,6 @@ public Config Populate(Config config)
             IncludeTypeInfo = config.IncludeTypeInfo;
             TypeAttr = config.TypeAttr;
             DateTimeFormat = config.DateTimeFormat;
-            JsonTypeAttrInObject = config.JsonTypeAttrInObject;
-            JsvTypeAttrInObject = config.JsvTypeAttrInObject;
             TypeWriter = config.TypeWriter;
             TypeFinder = config.TypeFinder;
             ParsePrimitiveFn = config.ParsePrimitiveFn;

src/ServiceStack.Text/TypeConfig.cs

@@ -30,8 +30,7 @@ public static class TypeConfig<T>
     {
         internal static TypeConfig config;
 
-        static TypeConfig Config => 
-            config ?? (config = Create());
+        static TypeConfig Config => config ??= Create();
 
         public static PropertyInfo[] Properties
         {

tests/ServiceStack.Text.Tests/RuntimeSerializationTests.cs

@@ -300,6 +300,37 @@ public void Can_serialize_JS_literal_into_DTO()
             JS.UnConfigure();
         }
 
+        [Test]
+        public void ServiceStack_AllowRuntimeType()
+        {
+            // Initialize static delegate to allow all types to be deserialized with the type attribute
+            JsConfig.AllowRuntimeType = _ => true;
+            JsConfig.TypeAttr = "$type";
+            var example = new Example { Property = new MyProperty { Value = "Hello serializer" } };
+
+            var serialized = JsonSerializer.SerializeToString(example);
+            var deserialized = JsonSerializer.DeserializeFromString<Example>(serialized);
+            Assert.IsNotNull(deserialized?.Property);
+
+            // Now the same process with a config scope that has a TypeAttr that differs from the global TypeAttr value
+            using var scope = JsConfig.With(new Config { TypeAttr = "_type" });
+            serialized = JsonSerializer.SerializeToString(example);
+            deserialized = JsonSerializer.DeserializeFromString<Example>(serialized);
+            Assert.IsNotNull(deserialized?.Property);
+            
+            JsConfig.Reset();
+        }
 
+        private class Example
+        {
+            public IProperty Property { get; set; }
+        }
+        private interface IProperty
+        {
+        }
+        private class MyProperty : IProperty
+        {
+            public string Value { get; set; }
+        }
     }
 }