some star yielding

Author: lahma

Jint/Native/JsValue.cs

@@ -37,7 +37,7 @@ internal JsValue(InternalTypes type)
 
         [Pure]
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        internal IIterator GetIterator(Realm realm, GeneratorKind hint = GeneratorKind.Sync, ICallable method = null)
+        internal IteratorInstance GetIterator(Realm realm, GeneratorKind hint = GeneratorKind.Sync, ICallable method = null)
         {
             if (!TryGetIterator(realm, out var iterator, hint, method))
             {
@@ -49,7 +49,7 @@ internal IIterator GetIterator(Realm realm, GeneratorKind hint = GeneratorKind.S
 
         [Pure]
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        internal bool TryGetIterator(Realm realm, out IIterator iterator, GeneratorKind hint = GeneratorKind.Sync, ICallable method = null)
+        internal bool TryGetIterator(Realm realm, out IteratorInstance iterator, GeneratorKind hint = GeneratorKind.Sync, ICallable method = null)
         {
             var obj = TypeConverter.ToObject(realm, this);
 
@@ -84,7 +84,7 @@ internal bool TryGetIterator(Realm realm, out IIterator iterator, GeneratorKind
                 ExceptionHelper.ThrowTypeError(realm, "Result of the Symbol.iterator method is not an object");
             }
 
-            if (iteratorResult is IIterator i)
+            if (iteratorResult is IteratorInstance i)
             {
                 iterator = i;
             }

Jint/Runtime/Interpreter/Expressions/JintYieldExpression.cs

@@ -1,6 +1,7 @@
 using Esprima.Ast;
 using Jint.Native;
 using Jint.Native.Generator;
+using Jint.Native.Iterator;
 using Jint.Native.Object;
 
 namespace Jint.Runtime.Interpreter.Expressions
@@ -33,21 +34,20 @@ protected override ExpressionResult EvaluateInternal(EvaluationContext context)
 
             if (expression.Delegate)
             {
-                ExceptionHelper.ThrowNotImplementedException();
-                // TODO return YieldDelegate(value);
+                value = YieldDelegate(value);
             }
 
             return new ExpressionResult(ExpressionCompletionType.Return, Yield(value), _expression.Location);
         }
 
-        /*
         /// <summary>
         /// https://tc39.es/ecma262/#sec-generator-function-definitions-runtime-semantics-evaluation
         /// </summary>
-        private object YieldDelegate(JsValue value)
+        private JsValue YieldDelegate(JsValue value)
         {
             var generatorKind = _engine.ExecutionContext.GetGeneratorKind();
             var iterator = value.GetIterator(_engine.Realm, generatorKind);
+            var iteratorRecord = iterator;
             var received = new Completion(CompletionType.Normal, JsValue.Undefined, default);
             while (true)
             {
@@ -83,9 +83,9 @@ private object YieldDelegate(JsValue value)
                 else if (received.Type == CompletionType.Throw)
                 {
                     var throwMethod = iterator.GetMethod("throw");
-                    if (!throwMethod.IsUndefined())
+                    if (throwMethod is not null)
                     {
-                        var innerResult = throwMethod.Call(iterator, « received.[[Value]] »));
+                        var innerResult = throwMethod.Call(iterator, new[]{ received.Value });
                         if (generatorKind == GeneratorKind.Async)
                         {
                             innerResult = Await(innerResult);
@@ -97,8 +97,8 @@ private object YieldDelegate(JsValue value)
                             ExceptionHelper.ThrowTypeError(_engine.Realm);
                         }
 
-                        done = IteratorComplete(innerResult);
-                        if (done is true)
+                        var done = IteratorComplete(innerResult);
+                        if (done)
                         {
                             IteratorValue(innerResult);
                         }
@@ -119,11 +119,11 @@ private object YieldDelegate(JsValue value)
                         var closeCompletion = new Completion(CompletionType.Normal, null, "", _expression.Location);
                         if (generatorKind == GeneratorKind.Async)
                         {
-                            AsyncIteratorClose(iteratorRecord, closeCompletion);
+                            AsyncIteratorClose(iteratorRecord, CompletionType.Normal);
                         }
                         else
                         {
-                            IteratorClose(iteratorRecord, closeCompletion);
+                            iteratorRecord.Close(CompletionType.Normal);
                         }
 
                         ExceptionHelper.ThrowTypeError(_engine.Realm, "Iterator does not have close method");
@@ -134,12 +134,13 @@ private object YieldDelegate(JsValue value)
                     var returnMethod = iterator.GetMethod("return");
                     if (returnMethod is null)
                     {
+                        var temp = received.Value;
                         if (generatorKind == GeneratorKind.Async)
                         {
-                            received.Value = Await(received.Value);
+                            temp = Await(received.Value);
                         }
 
-                        return received;
+                        return temp;
                     }
 
                     var innerReturnResult = returnMethod.Call(iterator, received.Value);
@@ -156,8 +157,8 @@ private object YieldDelegate(JsValue value)
                      var done = IteratorComplete(innerReturnResult);
                      if (done)
                      {
-                         var value = IteratorValue(innerReturnResult);
-                         return new Completion(CompletionType.Return, value, "", _expression.Location);
+                         var val = IteratorValue(innerReturnResult);
+                         return val;
                      }
 
                      if (generatorKind == GeneratorKind.Async)
@@ -167,30 +168,44 @@ private object YieldDelegate(JsValue value)
                      else
                      {
                          received = GeneratorYield(innerReturnResult);
-
                      }
                 }
             }
         }
-*/
-        private void AsyncIteratorClose(object iteratorRecord, Completion closeCompletion)
+
+        private Completion GeneratorYield(JsValue innerResult)
+        {
+            throw new System.NotImplementedException();
+        }
+
+        private static bool IteratorComplete(JsValue iterResult)
+        {
+            return TypeConverter.ToBoolean(iterResult.Get(CommonProperties.Done));
+        }
+
+        private static JsValue IteratorValue(JsValue iterResult)
+        {
+            return iterResult.Get(CommonProperties.Value);
+        }
+
+        private void AsyncIteratorClose(object iteratorRecord, CompletionType closeCompletion)
         {
             ExceptionHelper.ThrowNotImplementedException("async");
         }
 
         /// <summary>
         /// https://tc39.es/ecma262/#sec-asyncgeneratoryield
         /// </summary>
-        private object AsyncGeneratorYield(object iteratorValue)
+        private Completion AsyncGeneratorYield(object iteratorValue)
         {
             ExceptionHelper.ThrowNotImplementedException("async");
-            return null;
+            return default;
         }
 
         /// <summary>
         /// https://tc39.es/ecma262/#await
         /// </summary>
-        private ObjectInstance Await(ObjectInstance innerResult)
+        private ObjectInstance Await(JsValue innerResult)
         {
             ExceptionHelper.ThrowNotImplementedException("await");
             return null;