Improve stringify for JObject

Jint.Tests/Runtime/InteropTests.NewtonsoftJson.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using Jint.Native;
 using Jint.Runtime;
 using Jint.Runtime.Interop;
 using Newtonsoft.Json.Linq;
@@ -90,5 +91,68 @@ public void EngineShouldStringifyAnJObjectListWithValuesCorrectly()
 
             Assert.Equal("{\"Current\":null}", result);
         }
+
+        [Fact]
+        public void EngineShouldStringifyJObjectFromObjectListWithValuesCorrectly()
+        {
+            var engine = new Engine(options =>
+            {
+                options.AddObjectConverter(JTokenConverter.Instance);
+            });
+
+            var source = new dynamic[]
+            {
+                new { Text = "Text1", Value = 1 },
+                new { Text = "Text2", Value = 2 }
+            };
+
+            engine.SetValue("testSubject", source.Select(x => JObject.FromObject(x)).ToList());
+            var fromEngine = engine.Evaluate("return JSON.stringify(testSubject);");
+            var result = fromEngine.ToString();
+
+            Assert.Equal("[{\"Text\":\"Text1\",\"Value\":1},{\"Text\":\"Text2\",\"Value\":2}]", result);
+        }
+
+        private sealed class JTokenConverter : IObjectConverter
+        {
+            public static readonly IObjectConverter Instance = new JTokenConverter();
+
+            public bool TryConvert(Engine engine, object value, out JsValue result)
+            {
+                result = null;
+
+                if (!(value is JToken token))
+                {
+                    return false;
+                }
+
+                switch (token.Type)
+                {
+                    case JTokenType.Integer:
+                        result = JsNumber.Create(token.Value<int>());
+                        break;
+                    case JTokenType.Float:
+                        result = JsNumber.Create(token.Value<double>());
+                        break;
+                    case JTokenType.String:
+                        result = JsString.Create(token.Value<string>());
+                        break;
+                    case JTokenType.Boolean:
+                        result = token.Value<bool>() ? JsBoolean.True : JsBoolean.False;
+                        break;
+                    case JTokenType.Null:
+                        result = JsValue.Null;
+                        break;
+                    case JTokenType.Undefined:
+                        result = JsValue.Undefined;
+                        break;
+                    case JTokenType.Date:
+                        result = engine.Realm.Intrinsics.Date.Construct(token.Value<DateTime>());
+                        break;
+                }
+
+                return !(result is null);
+            }
+        }
     }
 }

Jint/Runtime/Interop/ObjectWrapper.cs

@@ -98,37 +98,6 @@ public override JsValue Get(JsValue property, JsValue receiver)
                 return Undefined;
             }
 
-            if (property is JsString stringKey)
-            {
-                var member = stringKey.ToString();
-
-                // expando object for instance
-                if (_typeDescriptor.IsStringKeyedGenericDictionary)
-                {
-                    if (_typeDescriptor.TryGetValue(Target, member, out var value))
-                    {
-                        return FromObject(_engine, value);
-                    }
-                }
-
-                var result = Engine.Options.Interop.MemberAccessor?.Invoke(Engine, Target, member);
-                if (result is not null)
-                {
-                    return result;
-                }
-
-                if (_properties is null || !_properties.ContainsKey(member))
-                {
-                    // can try utilize fast path
-                    var accessor = _engine.Options.Interop.TypeResolver.GetAccessor(_engine, Target.GetType(), member);
-                    var value = accessor.GetValue(_engine, Target);
-                    if (value is not null)
-                    {
-                        return FromObject(_engine, value);
-                    }
-                }
-            }
-
             return base.Get(property, receiver);
         }
 
@@ -152,9 +121,10 @@ private IEnumerable<JsValue> EnumerateOwnPropertyKeys(Types types)
             var processed = basePropertyKeys.Count > 0 ? new HashSet<JsValue>() : null;
 
             var includeStrings = (types & Types.String) != 0;
-            if (includeStrings && Target is IDictionary<string, object> stringKeyedDictionary) // expando object for instance
+            if (includeStrings && _typeDescriptor.IsStringKeyedGenericDictionary) // expando object for instance
             {
-                foreach (var key in stringKeyedDictionary.Keys)
+                var keys = _typeDescriptor.GetKeys(Target);
+                foreach (var key in keys)
                 {
                     var jsString = JsString.Create(key);
                     processed?.Add(jsString);
@@ -166,7 +136,9 @@ private IEnumerable<JsValue> EnumerateOwnPropertyKeys(Types types)
                 // we take values exposed as dictionary keys only
                 foreach (var key in dictionary.Keys)
                 {
-                    if (_engine.ClrTypeConverter.TryConvert(key, typeof(string), CultureInfo.InvariantCulture, out var stringKey))
+                    object stringKey = key as string;
+                    if (stringKey is not null
+                        || _engine.ClrTypeConverter.TryConvert(key, typeof(string), CultureInfo.InvariantCulture, out stringKey))
                     {
                         var jsString = JsString.Create((string) stringKey);
                         processed?.Add(jsString);
@@ -234,6 +206,15 @@ public override PropertyDescriptor GetOwnProperty(JsValue property)
             }
 
             var member = property.ToString();
+
+            if (_typeDescriptor.IsStringKeyedGenericDictionary)
+            {
+                if (_typeDescriptor.TryGetValue(Target, member, out var value))
+                {
+                    return new PropertyDescriptor(FromObject(_engine, value), PropertyFlag.OnlyEnumerable);
+                }
+            }
+
             var result = Engine.Options.Interop.MemberAccessor(Engine, Target, member);
             if (result is not null)
             {

Jint/Runtime/Interop/TypeDescriptor.cs

@@ -13,6 +13,7 @@ internal sealed class TypeDescriptor
         private static readonly Type _stringType = typeof(string);
 
         private readonly PropertyInfo _stringIndexer;
+        private readonly PropertyInfo _keysAccessor;
 
         private TypeDescriptor(Type type)
         {
@@ -24,6 +25,7 @@ private TypeDescriptor(Type type)
                     && i.GenericTypeArguments[0] == _stringType)
                 {
                     _stringIndexer = i.GetProperty("Item");
+                    _keysAccessor = i.GetProperty("Keys");
                     break;
                 }
             }
@@ -99,5 +101,15 @@ public bool TryGetValue(object target, string member, out object o)
                 return false;
             }
         }
+
+        public ICollection<string> GetKeys(object target)
+        {
+            if (!IsStringKeyedGenericDictionary)
+            {
+                ExceptionHelper.ThrowInvalidOperationException("Not a string-keyed dictionary");
+            }
+
+            return (ICollection<string>)_keysAccessor.GetValue(target);
+        }
     }
 }