In JavaScriptEngineSwitcher.ChakraCore an attempt was made to prevent occurrence of the access violation exception in the CallFunction method

Author: Taritsyn

NuGet/JavaScriptEngineSwitcher.ChakraCore/JavaScriptEngineSwitcher.ChakraCore.nuspec

@@ -20,6 +20,7 @@ This package does not contain the native implementations of ChakraCore. Therefor
  * JavaScriptEngineSwitcher.ChakraCore.Native.debian-x64
  * JavaScriptEngineSwitcher.ChakraCore.Native.osx-x64</description>
 		<summary>JavaScriptEngineSwitcher.ChakraCore contains adapter `ChakraCoreJsEngine` (wrapper for the ChakraCore).</summary>
+		<releaseNotes>Attempt to prevent occurrence of the access violation exception in the `CallFunction` method.</releaseNotes>
 		<copyright>Copyright (c) 2013-2016 Andrey Taritsyn - http://www.taritsyn.ru</copyright>
 		<language>en-US</language>
 		<tags>JavaScriptEngineSwitcher JavaScript ECMAScript ChakraCore</tags>

NuGet/JavaScriptEngineSwitcher.ChakraCore/readme.txt

@@ -27,6 +27,12 @@
     * JavaScriptEngineSwitcher.ChakraCore.Native.debian-x64
     * JavaScriptEngineSwitcher.ChakraCore.Native.osx-x64
 
+   =============
+   RELEASE NOTES
+   =============
+   Attempt to prevent occurrence of the access violation exception in the
+   `CallFunction` method.
+
    =============
    DOCUMENTATION
    =============

src/JavaScriptEngineSwitcher.ChakraCore/ChakraCoreJsEngine.cs

@@ -241,7 +241,7 @@ private JsValue MapToScriptType(object value)
 			switch (typeCode)
 			{
 				case TypeCode.Boolean:
-					return JsValue.FromBoolean((bool)value);
+					return (bool)value ? JsValue.True : JsValue.False;
 
 				case TypeCode.SByte:
 				case TypeCode.Byte:
@@ -335,6 +335,50 @@ private object[] MapToHostType(JsValue[] args)
 			return args.Select(MapToHostType).ToArray();
 		}
 
+		/// <summary>
+		/// Adds a reference to the value
+		/// </summary>
+		/// <param name="value">The value</param>
+		private static void AddReferenceToValue(JsValue value)
+		{
+			if (CanHaveReferences(value))
+			{
+				value.AddRef();
+			}
+		}
+
+		/// <summary>
+		/// Removes a reference to the value
+		/// </summary>
+		/// <param name="value">The value</param>
+		private static void RemoveReferenceToValue(JsValue value)
+		{
+			if (CanHaveReferences(value))
+			{
+				value.Release();
+			}
+		}
+
+		/// <summary>
+		/// Checks whether the value can have references
+		/// </summary>
+		/// <param name="value">The value</param>
+		/// <returns>Result of check (true - may have; false - may not have)</returns>
+		private static bool CanHaveReferences(JsValue value)
+		{
+			JsValueType valueType = value.ValueType;
+
+			switch (valueType)
+			{
+				case JsValueType.Null:
+				case JsValueType.Undefined:
+				case JsValueType.Boolean:
+					return false;
+				default:
+					return true;
+			}
+		}
+
 		private JsValue FromObject(object value)
 		{
 			var del = value as Delegate;
@@ -951,11 +995,30 @@ protected override object InnerCallFunction(string functionName, params object[]
 						string.Format(CoreStrings.Runtime_FunctionNotExist, functionName));
 				}
 
-				var processedArgs = MapToScriptType(args);
-				var allProcessedArgs = new[] { globalObj }.Concat(processedArgs).ToArray();
-
+				JsValue resultValue;
 				JsValue functionValue = globalObj.GetProperty(functionId);
-				JsValue resultValue = functionValue.CallFunction(allProcessedArgs);
+
+				if (args.Length > 0)
+				{
+					JsValue[] processedArgs = MapToScriptType(args);
+
+					foreach (JsValue processedArg in processedArgs)
+					{
+						AddReferenceToValue(processedArg);
+					}
+
+					JsValue[] allProcessedArgs = new[] { globalObj }.Concat(processedArgs).ToArray();
+					resultValue = functionValue.CallFunction(allProcessedArgs);
+
+					foreach (JsValue processedArg in processedArgs)
+					{
+						RemoveReferenceToValue(processedArg);
+					}
+				}
+				else
+				{
+					resultValue = functionValue.CallFunction(globalObj);
+				}
 
 				return MapToHostType(resultValue);
 			});