tweaks

Jint/Engine.cs

@@ -383,7 +383,7 @@ internal Engine Execute(Script script, bool resetState)
                     script,
                     GlobalEnvironment);
 
-                var list = new JintStatementList(this, null, script.Body);
+                var list = new JintStatementList(this, script);
 
                 var result = list.Execute();
                 if (result.Type == CompletionType.Throw)
@@ -870,12 +870,12 @@ private void GlobalDeclarationInstantiation(
         /// </summary>
         internal ArgumentsInstance FunctionDeclarationInstantiation(
             FunctionInstance functionInstance,
-            JsValue[] argumentsList,
-            EnvironmentRecord env)
+            JsValue[] argumentsList)
         {
+            var env = ExecutionContext.LexicalEnvironment;
+            var envRec = (FunctionEnvironmentRecord) env;
             var func = functionInstance._functionDefinition;
 
-            var envRec = (FunctionEnvironmentRecord) env;
             var strict = StrictModeScope.IsStrictModeCode;
 
             var configuration = func.Initialize(this, functionInstance);

Jint/Native/Function/FunctionInstance.cs

@@ -308,14 +308,9 @@ protected void OrdinaryCallBindThis(ExecutionContext calleeContext, JsValue this
             localEnv.BindThisValue(thisValue);
         }
 
-        protected Completion OrdinaryCallEvaluateBody(
-            JsValue[] arguments,
-            ExecutionContext calleeContext)
+        protected internal Completion OrdinaryCallEvaluateBody(JsValue[] arguments)
         {
-            var argumentsInstance = _engine.FunctionDeclarationInstantiation(
-                functionInstance: this,
-                arguments,
-                calleeContext.LexicalEnvironment);
+            var argumentsInstance = _engine.FunctionDeclarationInstantiation(functionInstance: this, arguments);
 
             var result = _functionDefinition.Execute();
             var value = result.GetValueOrDefault().Clone();

Jint/Native/Function/ScriptFunctionInstance.cs

@@ -64,7 +64,7 @@ public override JsValue Call(JsValue thisArgument, JsValue[] arguments)
             {
                 try
                 {
-                    var result = OrdinaryCallEvaluateBody(arguments, calleeContext);
+                    var result = OrdinaryCallEvaluateBody(arguments);
 
                     if (result.Type == CompletionType.Throw)
                     {
@@ -117,7 +117,7 @@ public ObjectInstance Construct(JsValue[] arguments, JsValue newTarget)
             {
                 try
                 {
-                    var result = OrdinaryCallEvaluateBody(arguments, calleeContext);
+                    var result = OrdinaryCallEvaluateBody(arguments);
 
                     if (result.Type == CompletionType.Return)
                     {

Jint/Native/Generator/Generator.cs

@@ -1,8 +1,8 @@
-using Esprima.Ast;
+using Jint.Native.Function;
+using Jint.Native.Iterator;
 using Jint.Native.Object;
 using Jint.Runtime;
 using Jint.Runtime.Environments;
-using Jint.Runtime.Interpreter;
 
 namespace Jint.Native.Generator
 {
@@ -14,7 +14,7 @@ internal sealed class Generator : ObjectInstance
         internal GeneratorState _generatorState;
         private ExecutionContext _generatorContext;
         private readonly object _generatorBrand = null;
-        private JintStatementList _generatorBody;
+        private FunctionInstance _generatorBody;
 
         public Generator(Engine engine) : base(engine)
         {
@@ -24,11 +24,10 @@ public Generator(Engine engine) : base(engine)
         /// <summary>
         /// https://tc39.es/ecma262/#sec-generatorstart
         /// </summary>
-        public JsValue GeneratorStart(IFunction generatorBody)
+        public JsValue GeneratorStart(FunctionInstance generatorBody)
         {
             var genContext = _engine.UpdateGenerator(this);
-            var blockStatement = (BlockStatement) generatorBody.Body;
-            _generatorBody ??= new JintStatementList(_engine, blockStatement, blockStatement.Body);
+            _generatorBody = generatorBody;
 
             /*
              *Set the code evaluation state of genContext such that when evaluation is resumed for that execution context the following steps will be performed:
@@ -63,7 +62,7 @@ public JsValue GeneratorResume(JsValue value, object generatorBrand)
             var state = GeneratorValidate(generatorBrand);
             if (state == GeneratorState.Completed)
             {
-                return CreateIterResultObject(Undefined, true);
+                return new IteratorResult(_engine, Undefined, JsBoolean.True);
             }
 
             var genContext = _generatorContext;
@@ -75,10 +74,10 @@ public JsValue GeneratorResume(JsValue value, object generatorBrand)
             _engine.EnterExecutionContext(genContext);
 
             // TODO
-            var result = _generatorBody.Execute();
+            var result = _generatorBody._functionDefinition.Execute();
 
             return result.Value.IsUndefined()
-                ? CreateIterResultObject(Undefined, done: true)
+                ? new IteratorResult(_engine, Undefined, JsBoolean.True)
                 : result.Value;
         }
 
@@ -98,7 +97,7 @@ public JsValue GeneratorResumeAbrupt(in Completion abruptCompletion, object gene
             {
                 if (abruptCompletion.Type == CompletionType.Return)
                 {
-                    return CreateIterResultObject(abruptCompletion.Value, true);
+                    return new IteratorResult(_engine, abruptCompletion.Value, JsBoolean.True);
                 }
 
                 return abruptCompletion.Value;
@@ -114,7 +113,7 @@ public JsValue GeneratorResumeAbrupt(in Completion abruptCompletion, object gene
             _engine.EnterExecutionContext(genContext);
 
             // Resume the suspended evaluation of genContext using abruptCompletion as the result of the operation that suspended it. Let result be the completion record returned by the resumed computation.
-            var result = _generatorBody.Execute();
+            var result = _generatorBody.OrdinaryCallEvaluateBody(Arguments.Empty);
 
             return result.Value;
         }

Jint/Native/Generator/GeneratorFunctionInstance.cs

@@ -9,11 +9,11 @@ namespace Jint.Native.Generator
     /// </summary>
     internal sealed class GeneratorFunctionInstance : FunctionInstance
     {
-        private readonly FunctionInstance _functionInstance;
+        private readonly FunctionInstance _functionBody;
 
-        public GeneratorFunctionInstance(Engine engine, FunctionInstance functionInstance) : base(engine, JsString.Empty)
+        public GeneratorFunctionInstance(Engine engine, FunctionInstance functionBody) : base(engine, JsString.Empty)
         {
-            _functionInstance = functionInstance;
+            _functionBody = functionBody;
             _prototype = _engine.GeneratorFunction.PrototypeObject;
             var prototype = new ObjectInstance(_engine)
             {
@@ -22,11 +22,15 @@ public GeneratorFunctionInstance(Engine engine, FunctionInstance functionInstanc
             _prototypeDescriptor = new PropertyDescriptor(prototype, PropertyFlag.Writable);
         }
 
-        public override JsValue Call(JsValue thisObject, JsValue[] arguments)
+        /// <summary>
+        /// https://tc39.es/ecma262/#sec-generator-function-definitions-runtime-semantics-evaluatebody
+        /// </summary>
+        public override JsValue Call(JsValue functionObject, JsValue[] arguments)
         {
-            var generator = new Generator(_engine);
-            generator.GeneratorStart(_functionInstance.FunctionDeclaration);
-            return generator;
+            _engine.FunctionDeclarationInstantiation(_functionBody, arguments);
+            var G = OrdinaryCreateFromConstructor(functionObject, _engine.GeneratorFunction.PrototypeObject.Prototype, (engine, _) => new Generator(engine));
+            G.GeneratorStart(_functionBody);
+            return G;
         }
     }
 }

Jint/Native/Iterator/IIterator.cs

@@ -5,7 +5,7 @@ namespace Jint.Native.Iterator
 {
     internal interface IIterator
     {
-        bool IteratorStep(out ObjectInstance nextItem);
+        bool TryIteratorStep(out ObjectInstance nextItem);
         void Close(CompletionType completion);
     }
 }

Jint/Native/Iterator/IteratorInstance.cs

@@ -38,7 +38,7 @@ public override bool Equals(JsValue other)
             return false;
         }
 
-        public virtual bool IteratorStep(out ObjectInstance nextItem)
+        public virtual bool TryIteratorStep(out ObjectInstance nextItem)
         {
             if (_enumerable.MoveNext())
             {
@@ -99,7 +99,7 @@ public MapIterator(Engine engine, MapInstance map) : base(engine)
                 _position = 0;
             }
 
-            public override bool IteratorStep(out ObjectInstance nextItem)
+            public override bool TryIteratorStep(out ObjectInstance nextItem)
             {
                 if (_position < _map.GetSize())
                 {
@@ -134,7 +134,7 @@ public ArrayLikeIterator(Engine engine, JsValue target) : base(engine)
                 _position = 0;
             }
 
-            public override bool IteratorStep(out ObjectInstance nextItem)
+            public override bool TryIteratorStep(out ObjectInstance nextItem)
             {
                 if (_end == null)
                 {
@@ -164,7 +164,7 @@ public SetIterator(Engine engine, SetInstance set) : base(engine)
                 _position = 0;
             }
 
-            public override bool IteratorStep(out ObjectInstance nextItem)
+            public override bool TryIteratorStep(out ObjectInstance nextItem)
             {
                 if (_position < _set._set._list.Count)
                 {
@@ -190,7 +190,7 @@ public SetEntryIterator(Engine engine, SetInstance set) : base(engine)
                 _position = 0;
             }
 
-            public override bool IteratorStep(out ObjectInstance nextItem)
+            public override bool TryIteratorStep(out ObjectInstance nextItem)
             {
                 if (_position < _set._set._list.Count)
                 {
@@ -217,7 +217,7 @@ public ListIterator(Engine engine, List<JsValue> values) : base(engine)
                 _position = 0;
             }
 
-            public override bool IteratorStep(out ObjectInstance nextItem)
+            public override bool TryIteratorStep(out ObjectInstance nextItem)
             {
                 if (!_closed && _position < _values.Count)
                 {
@@ -245,7 +245,7 @@ public ArrayLikeKeyIterator(Engine engine, ObjectInstance objectInstance) : base
                 _position = 0;
             }
 
-            public override bool IteratorStep(out ObjectInstance nextItem)
+            public override bool TryIteratorStep(out ObjectInstance nextItem)
             {
                 var length = _operations.GetLength();
                 if (!_closed && _position < length)
@@ -272,7 +272,7 @@ public ArrayLikeValueIterator(Engine engine, ObjectInstance objectInstance) : ba
                 _position = 0;
             }
 
-            public override bool IteratorStep(out ObjectInstance nextItem)
+            public override bool TryIteratorStep(out ObjectInstance nextItem)
             {
                 var length = _operations.GetLength();
                 if (!_closed && _position < length)
@@ -300,7 +300,7 @@ public ObjectIterator(ObjectInstance target)
                             ?? ExceptionHelper.ThrowTypeError<ICallable>(target.Engine);
             }
 
-            public bool IteratorStep(out ObjectInstance result)
+            public bool TryIteratorStep(out ObjectInstance result)
             {
                 result = IteratorNext();
 
@@ -357,7 +357,7 @@ public StringIterator(Engine engine, string str) : base(engine)
                 _iterator = StringInfo.GetTextElementEnumerator(str);
             }
 
-            public override bool IteratorStep(out ObjectInstance nextItem)
+            public override bool TryIteratorStep(out ObjectInstance nextItem)
             {
                 if (_iterator.MoveNext())
                 {
@@ -393,19 +393,19 @@ public RegExpStringIterator(Engine engine, ObjectInstance iteratingRegExp, strin
                 _unicode = unicode;
             }
 
-            public override bool IteratorStep(out ObjectInstance nextItem)
+            public override bool TryIteratorStep(out ObjectInstance nextItem)
             {
                 if (_done)
                 {
-                    nextItem = CreateIterResultObject(Undefined, true);
+                    nextItem = new IteratorResult(_engine, Undefined, JsBoolean.True);
                     return false;
                 }
 
                 var match  = RegExpPrototype.RegExpExec(_iteratingRegExp, _s);
                 if (match.IsNull())
                 {
                     _done = true;
-                    nextItem = CreateIterResultObject(Undefined, true);
+                    nextItem = new IteratorResult(_engine, Undefined, JsBoolean.True);
                     return false;
                 }
 
@@ -424,7 +424,7 @@ public override bool IteratorStep(out ObjectInstance nextItem)
                     _done = true;
                 }
 
-                nextItem = CreateIterResultObject(match, false);
+                nextItem = new IteratorResult(_engine, match, JsBoolean.False);
                 return false;
             }
         }

Jint/Native/Iterator/IteratorProtocol.cs

@@ -31,7 +31,7 @@ internal bool Execute()
             {
                 do
                 {
-                    if (!_iterator.IteratorStep(out var item))
+                    if (!_iterator.TryIteratorStep(out var item))
                     {
                         done = true;
                         break;
@@ -101,7 +101,7 @@ internal static void AddEntriesFromIterable(ObjectInstance target, IIterator ite
             {
                 do
                 {
-                    if (!iterable.IteratorStep(out var nextItem))
+                    if (!iterable.TryIteratorStep(out var nextItem))
                     {
                         return;
                     }

Jint/Native/Iterator/IteratorPrototype.cs

@@ -51,7 +51,7 @@ private JsValue Next(JsValue thisObj, JsValue[] arguments)
                 return ExceptionHelper.ThrowTypeError<JsValue>(_engine);
             }
 
-            iterator.IteratorStep(out var result);
+            iterator.TryIteratorStep(out var result);
             return result;
         }
     }

Jint/Native/Iterator/IteratorResult.cs

@@ -0,0 +1,45 @@
+using Jint.Native.Object;
+using Jint.Runtime;
+
+namespace Jint.Native.Iterator
+{
+    /// <summary>
+    /// https://tc39.es/ecma262/#sec-createiterresultobject
+    /// </summary>
+    internal class IteratorResult : ObjectInstance
+    {
+        private readonly JsValue _value;
+        private readonly JsBoolean _done;
+
+        public IteratorResult(Engine engine, JsValue value, JsBoolean done) : base(engine)
+        {
+            _value = value;
+            _done = done;
+        }
+
+        public override JsValue Get(JsValue property, JsValue receiver)
+        {
+            if (property == CommonProperties.Value)
+            {
+                return _value;
+            }
+
+            if (property == CommonProperties.Done)
+            {
+                return _done;
+            }
+
+            return base.Get(property, receiver);
+        }
+
+        public override object ToObject()
+        {
+            return this;
+        }
+
+        public override bool Equals(JsValue other)
+        {
+            return ReferenceEquals(this, other);
+        }
+    }
+}