In JavaScriptEngineSwitcher.ChakraCore prevented an occurrence of the “Host may not have set any promise continuation callback. Promises may not be executed.” error

Author: Taritsyn

NuGet/JavaScriptEngineSwitcher.ChakraCore/JavaScriptEngineSwitcher.ChakraCore.nuspec

@@ -21,7 +21,8 @@ This package does not contain the native implementations of ChakraCore. Therefor
  * JavaScriptEngineSwitcher.ChakraCore.Native.osx-x64</description>
 		<summary>JavaScriptEngineSwitcher.ChakraCore contains adapter `ChakraCoreJsEngine` (wrapper for the ChakraCore).</summary>
 		<releaseNotes>1. ChakraCore was updated to version 1.8.1;
-2. JavaScriptEngineSwitcher.ChakraCore.Native.debian-x64 package has been replaced by the JavaScriptEngineSwitcher.ChakraCore.Native.linux-x64 package.</releaseNotes>
+2. JavaScriptEngineSwitcher.ChakraCore.Native.debian-x64 package has been replaced by the JavaScriptEngineSwitcher.ChakraCore.Native.linux-x64 package;
+3. Prevented an occurrence of the “Host may not have set any promise continuation callback. Promises may not be executed.” error.</releaseNotes>
 		<copyright>Copyright (c) 2013-2018 Andrey Taritsyn - http://www.taritsyn.ru</copyright>
 		<language>en-US</language>
 		<tags>JavaScriptEngineSwitcher JavaScript ECMAScript ChakraCore</tags>

NuGet/JavaScriptEngineSwitcher.ChakraCore/readme.txt

@@ -32,7 +32,9 @@
    =============
    1. ChakraCore was updated to version 1.8.1;
    2. JavaScriptEngineSwitcher.ChakraCore.Native.debian-x64 package has been
-      replaced by the JavaScriptEngineSwitcher.ChakraCore.Native.linux-x64 package.
+      replaced by the JavaScriptEngineSwitcher.ChakraCore.Native.linux-x64 package;
+   3. Prevented an occurrence of the “Host may not have set any promise
+      continuation callback. Promises may not be executed.” error.
 
    =============
    DOCUMENTATION

src/JavaScriptEngineSwitcher.ChakraCore/ChakraCoreJsEngine.cs

@@ -57,6 +57,11 @@ public sealed class ChakraCoreJsEngine : JsEngineBase
 		/// </summary>
 		private JsObjectFinalizeCallback _externalObjectFinalizeCallback;
 
+		/// <summary>
+		/// Callback for continuation of promise
+		/// </summary>
+		private JsPromiseContinuationCallback _promiseContinuationCallback;
+
 		/// <summary>
 		/// List of native function callbacks
 		/// </summary>
@@ -112,7 +117,7 @@ static ChakraCoreJsEngine()
 #endif
 
 		/// <summary>
-		/// Constructs a instance of adapter for the ChakraCore JS engine
+		/// Constructs an instance of adapter for the ChakraCore JS engine
 		/// </summary>
 		public ChakraCoreJsEngine()
 			: this(new ChakraCoreSettings())
@@ -145,6 +150,7 @@ public ChakraCoreJsEngine(ChakraCoreSettings settings)
 			}
 
 			_externalObjectFinalizeCallback = ExternalObjectFinalizeCallback;
+			_promiseContinuationCallback = PromiseContinuationCallback;
 
 			_dispatcher.Invoke(() =>
 			{
@@ -222,7 +228,23 @@ private static bool CanHaveReferences(JsValue value)
 		/// <returns>Instance of JS scope</returns>
 		private JsScope CreateJsScope()
 		{
-			return new JsScope(_jsContext);
+			var jsScope = new JsScope(_jsContext);
+
+			JsRuntime.SetPromiseContinuationCallback(_promiseContinuationCallback, IntPtr.Zero);
+
+			return jsScope;
+		}
+
+		/// <summary>
+		/// The promise continuation callback
+		/// </summary>
+		/// <param name="task">The task, represented as a JavaScript function</param>
+		/// <param name="callbackState">The data argument to be passed to the callback</param>
+		private static void PromiseContinuationCallback(JsValue task, IntPtr callbackState)
+		{
+			task.AddRef();
+			task.CallFunction(JsValue.GlobalObject);
+			task.Release();
 		}
 
 		#region Mapping
@@ -1254,6 +1276,7 @@ private void Dispose(bool disposing)
 						_nativeFunctions.Clear();
 					}
 
+					_promiseContinuationCallback = null;
 					_externalObjectFinalizeCallback = null;
 				}
 			}

src/JavaScriptEngineSwitcher.ChakraCore/JsRt/JsRuntime.cs

@@ -131,6 +131,24 @@ public static JsRuntime Create(JsRuntimeAttributes attributes, JsThreadServiceCa
 			return handle;
 		}
 
+		/// <summary>
+		/// Sets a promise continuation callback function that is called by the context when a task
+		/// needs to be queued for future execution
+		/// </summary>
+		/// <remarks>
+		/// <para>
+		/// Requires an active script context.
+		/// </para>
+		/// </remarks>
+		/// <param name="promiseContinuationCallback">The callback function being set</param>
+		/// <param name="callbackState">User provided state that will be passed back to the callback</param>
+		public static void SetPromiseContinuationCallback(JsPromiseContinuationCallback promiseContinuationCallback,
+			IntPtr callbackState)
+		{
+			JsErrorHelpers.ThrowIfError(NativeMethods.JsSetPromiseContinuationCallback(promiseContinuationCallback,
+				callbackState));
+		}
+
 		/// <summary>
 		/// Performs a full garbage collection
 		/// </summary>

test/JavaScriptEngineSwitcher.Tests.Net4/JavaScriptEngineSwitcher.Tests.Net40.csproj

@@ -99,6 +99,9 @@
     <Compile Include="..\JavaScriptEngineSwitcher.Tests\ChakraCore\CommonTests.cs">
       <Link>ChakraCore\CommonTests.cs</Link>
     </Compile>
+    <Compile Include="..\JavaScriptEngineSwitcher.Tests\ChakraCore\Es2015Tests.cs">
+      <Link>ChakraCore\Es2015Tests.cs</Link>
+    </Compile>
     <Compile Include="..\JavaScriptEngineSwitcher.Tests\ChakraCore\Es5Tests.cs">
       <Link>ChakraCore\Es5Tests.cs</Link>
     </Compile>
@@ -108,6 +111,9 @@
     <Compile Include="..\JavaScriptEngineSwitcher.Tests\CommonTestsBase.cs">
       <Link>CommonTestsBase.cs</Link>
     </Compile>
+    <Compile Include="..\JavaScriptEngineSwitcher.Tests\Es2015TestsBase.cs">
+      <Link>Es2015TestsBase.cs</Link>
+    </Compile>
     <Compile Include="..\JavaScriptEngineSwitcher.Tests\Es5TestsBase.cs">
       <Link>Es5TestsBase.cs</Link>
     </Compile>
@@ -198,6 +204,9 @@
     <Compile Include="..\JavaScriptEngineSwitcher.Tests\V8\CommonTests.cs">
       <Link>V8\CommonTests.cs</Link>
     </Compile>
+    <Compile Include="..\JavaScriptEngineSwitcher.Tests\V8\Es2015Tests.cs">
+      <Link>V8\Es2015Tests.cs</Link>
+    </Compile>
     <Compile Include="..\JavaScriptEngineSwitcher.Tests\V8\Es5Tests.cs">
       <Link>V8\Es5Tests.cs</Link>
     </Compile>

test/JavaScriptEngineSwitcher.Tests/ChakraCore/Es2015Tests.cs

@@ -0,0 +1,10 @@
+namespace JavaScriptEngineSwitcher.Tests.ChakraCore
+{
+	public class Es2015Tests : Es2015TestsBase
+	{
+		protected override string EngineName
+		{
+			get { return "ChakraCoreJsEngine"; }
+		}
+	}
+}

test/JavaScriptEngineSwitcher.Tests/Es2015TestsBase.cs

@@ -0,0 +1,57 @@
+using System;
+using System.Text;
+
+using Xunit;
+
+namespace JavaScriptEngineSwitcher.Tests
+{
+	public abstract class Es2015TestsBase : TestsBase
+	{
+		#region Promises
+
+		[Fact]
+		public virtual void ExecutionOfPromisesIsCorrect()
+		{
+			// Arrange
+			var stringBuilder = new StringBuilder();
+			const string input = @"var successfulWork = new Promise(function(resolve, reject) {
+	resolve(""Success!"");
+});
+
+var unsuccessfulWork = new Promise(function (resolve, reject) {
+	reject(""Fail!"");
+});
+
+function resolveCallback(result) {
+	stringBuilder.AppendLine('Resolved: ' + result);
+}
+
+function rejectCallback(reason) {
+	stringBuilder.AppendLine('Rejected: ' + reason);
+}
+
+successfulWork.then(resolveCallback, rejectCallback);
+unsuccessfulWork.then(resolveCallback, rejectCallback);";
+			string targetOutput = "Resolved: Success!" + Environment.NewLine +
+				"Rejected: Fail!" + Environment.NewLine
+				;
+
+			// Act
+			string output;
+
+			using (var jsEngine = CreateJsEngine())
+			{
+				jsEngine.EmbedHostObject("stringBuilder", stringBuilder);
+				jsEngine.Execute(input);
+
+				output = stringBuilder.ToString();
+				stringBuilder.Clear();
+			}
+
+			// Assert
+			Assert.Equal(targetOutput, output);
+		}
+
+		#endregion
+	}
+}

test/JavaScriptEngineSwitcher.Tests/V8/Es2015Tests.cs

@@ -0,0 +1,12 @@
+#if !NETCOREAPP1_0
+namespace JavaScriptEngineSwitcher.Tests.V8
+{
+	public class Es2015Tests : Es2015TestsBase
+	{
+		protected override string EngineName
+		{
+			get { return "V8JsEngine"; }
+		}
+	}
+}
+#endif