.

Author: rogeralsing

continue.md

@@ -21,9 +21,10 @@
 - Private name assignments now route through private scope/brand resolution, so instance/static private setter brand-checks across multiple class evaluations (factory/eval/realm variants) are passing alongside the private static getter/setter cases.
 - Super() in derived class constructors now finds the owning `this` binding without triggering TDZ ReferenceErrors, so the `this-access-restriction` class definition cases are green in strict and sloppy mode.
 - Logical assignment short-circuits skip `PutValue` (including private refs/accessors), and RHS NamedEvaluation now applies to ||=/&&=/??= with identifier LHS, so the logical-assignment cluster (read-only/accessor/non-extensible and name inference) is green.
-- `using` and `await using` declarations parse correctly and throw TypeError on non-object initializers, so the explicit resource management statement cases now pass.
+- Array index assignments now walk prototype accessors/writable descriptors (including inherited setters) before falling back to element storage, so member-expression for-in targets trigger Array.prototype setters and typed array for-in over resizable buffers enumerates the expected indices.
+- `using` and `await using` declarations still TypeError on non-object initializers but now allow initializer-less for-in/of heads with per-iteration lexical environments, so the TDZ/fresh-binding for-of cases are green.
 
 ## Next Iteration Plan
-1. Re-run the Language suite to refresh the current failure set after the this-access/super binding fixes.
+1. Re-run the Language suite to refresh the current failure set after the for-in/of using and array setter fixes.
 2. Triage the next largest failing cluster from that run (modules/import/defer if they resurface, otherwise whatever is hottest), adding realm logging if the failure isn’t obvious.
 3. Iterate through the refreshed list in priority order, landing targeted fixes and re-running the filtered clusters as they’re addressed.

languagetests.md

@@ -85,7 +85,6 @@
         ModuleCode_topLevelAwait("language/module-code/top-level-await/module-graphs-does-not-hang.js",True)
         ModuleCode_topLevelAwait("language/module-code/top-level-await/module-sync-import-async-resolution-ticks.js",True)
        ModuleCode_topLevelAwait_syntax
-        ModuleCode_topLevelAwait_syntax("language/module-code/top-level-await/syntax/await-expr-dyn-import.js",True)
        Statements_asyncGenerator
         Statements_asyncGenerator("language/statements/async-generator/yield-star-async-from-sync-iterator-inaccessible.js",False)
         Statements_asyncGenerator("language/statements/async-generator/yield-star-async-from-sync-iterator-inaccessible.js",True)
@@ -122,18 +121,6 @@
         Statements_forAwaitOf("language/statements/for-await-of/async-gen-decl-dstr-array-elem-target-simple-no-strict.js",False)
         Statements_forAwaitOf("language/statements/for-await-of/async-gen-decl-dstr-obj-id-init-simple-no-strict.js",False)
         Statements_forAwaitOf("language/statements/for-await-of/async-gen-decl-dstr-obj-id-simple-no-strict.js",False)
-       Statements_forIn
-        Statements_forIn("language/statements/for-in/head-lhs-let.js",False)
-        Statements_forIn("language/statements/for-in/resizable-buffer.js",False)
-        Statements_forIn("language/statements/for-in/resizable-buffer.js",True)
-       Statements_forOf
-        Statements_forOf("language/statements/for-of/head-await-using-bound-names-fordecl-tdz.js",False)
-        Statements_forOf("language/statements/for-of/head-await-using-bound-names-fordecl-tdz.js",True)
-        Statements_forOf("language/statements/for-of/head-await-using-fresh-binding-per-iteration.js",True)
-        Statements_forOf("language/statements/for-of/head-using-bound-names-fordecl-tdz.js",False)
-        Statements_forOf("language/statements/for-of/head-using-bound-names-fordecl-tdz.js",True)
-        Statements_forOf("language/statements/for-of/head-using-fresh-binding-per-iteration.js",False)
-        Statements_forOf("language/statements/for-of/head-using-fresh-binding-per-iteration.js",True)
        Statements_function
         Statements_function("language/statements/function/param-dflt-yield-non-strict.js",False)
        Statements_labeled

src/Asynkron.JsEngine/Ast/ClassDefinitionExtensions.cs

@@ -81,7 +81,7 @@ public static partial class TypedAstEvaluator
                 }
 
                 typedFunction.SetInstanceFields(resolvedInstanceFields);
-                typedFunction.SetIsClassConstructor(superConstructor is not null);
+                typedFunction.SetIsClassConstructor(definition.Extends is not null);
                 typedFunction.SetPrivateNameScope(privateNameScope);
                 if (privateNameScope is not null)
                 {

src/Asynkron.JsEngine/Ast/TypedAstEvaluator.AsyncGeneratorFactory.cs

@@ -9,7 +9,7 @@ public static partial class TypedAstEvaluator
 {
     private sealed class AsyncGeneratorFactory : IJsCallable, IJsObjectLike, IPropertyDefinitionHost,
         IExtensibilityControl,
-        IFunctionNameTarget
+        IFunctionNameTarget, ICallableMetadata
     {
         private readonly JsEnvironment _closure;
         private readonly FunctionExpression _function;
@@ -115,6 +115,10 @@ public void EnsureHasName(string name, bool overwriteExisting = false)
         public bool IsSealed => _properties.IsSealed;
         public bool IsFrozen => _properties.IsFrozen;
 
+        public bool IsArrowFunction => false;
+        public bool DisallowConstruct => true;
+        public RealmState RealmState => _realmState;
+
         public IEnumerable<string> Keys => _properties.Keys;
 
         public void DefineProperty(string name, PropertyDescriptor descriptor)

src/Asynkron.JsEngine/Ast/TypedAstEvaluator.TypedFunction.cs

@@ -639,7 +639,7 @@ public bool TryDefineProperty(string name, PropertyDescriptor descriptor)
 
                 object? initialThisValue;
                 var initialThisInitialized = true;
-                if (_isDerivedClassConstructor && _superConstructor is not null)
+                if (_isDerivedClassConstructor)
                 {
                     context.MarkThisUninitialized();
                     initialThisInitialized = false;
@@ -708,7 +708,7 @@ public bool TryDefineProperty(string name, PropertyDescriptor descriptor)
 
                 if (_isClassConstructor && boundThis is JsObject thisInstance)
                 {
-                    if (_isDerivedClassConstructor && _superConstructor is not null)
+                    if (_isDerivedClassConstructor)
                     {
                         pendingFieldInitialization = new PendingClassFieldInitialization(this, functionEnvironment);
                         context.PushClassFieldInitializer(pendingFieldInitialization);

src/Asynkron.JsEngine/Ast/TypedAstEvaluator.TypedGeneratorFactory.cs

@@ -9,7 +9,7 @@ public static partial class TypedAstEvaluator
 {
     private sealed class TypedGeneratorFactory : IJsCallable, IJsObjectLike, IPropertyDefinitionHost,
         IExtensibilityControl,
-        IFunctionNameTarget, ICallerInfo
+        IFunctionNameTarget, ICallerInfo, ICallableMetadata
     {
         private readonly JsEnvironment _closure;
         private readonly FunctionExpression _function;
@@ -117,6 +117,10 @@ public void EnsureHasName(string name, bool overwriteExisting = false)
         public bool IsSealed => _properties.IsSealed;
         public bool IsFrozen => _properties.IsFrozen;
 
+        public bool IsArrowFunction => false;
+        public bool DisallowConstruct => true;
+        public RealmState RealmState => _realmState;
+
         public IEnumerable<string> Keys => _properties.Keys;
 
         public void DefineProperty(string name, PropertyDescriptor descriptor)

src/Asynkron.JsEngine/JsEngine.cs

@@ -964,12 +964,16 @@ private void EnsureModuleEvaluated(ModuleEntry entry)
     /// <summary>
     ///     Registers a value in the global scope.
     /// </summary>
-    private void SetGlobal(string name, object? value, bool isGlobalConstant = false)
+    private void SetGlobal(string name, object? value, bool isGlobalConstant = false, bool registerBinding = false)
     {
         var symbol = Symbol.Intern(name);
-        // Global built-ins are properties of the global object (ES GlobalDeclarationInstantiation),
-        // so they are registered as var-scoped bindings rather than lexical declarations.
-        GlobalEnvironment.Define(symbol, value, isGlobalConstant: isGlobalConstant, isLexical: false);
+        if (registerBinding)
+        {
+            // Only register a binding when explicitly requested (e.g., host-added globals).
+            // Built-ins defined during engine initialization are exposed as global object
+            // properties so they don't block later lexical declarations (let/const).
+            GlobalEnvironment.Define(symbol, value, isGlobalConstant: isGlobalConstant, isLexical: false);
+        }
 
         // Also mirror globals onto the global object so that code using
         // `this.foo` or `global.foo` can see host-provided bindings.
@@ -1003,15 +1007,15 @@ private void SetGlobal(string name, object? value, bool isGlobalConstant = false
     /// </summary>
     public void SetGlobalValue(string name, object? value)
     {
-        SetGlobal(name, value);
+        SetGlobal(name, value, registerBinding: true);
     }
 
     /// <summary>
     ///     Registers a host function that can be invoked from interpreted code.
     /// </summary>
     public void SetGlobalFunction(string name, Func<IReadOnlyList<object?>, object?> handler)
     {
-        GlobalEnvironment.Define(Symbol.Intern(name), new HostFunction(handler) { Realm = GlobalObject });
+        SetGlobal(name, new HostFunction(handler) { Realm = GlobalObject }, registerBinding: true);
     }
 
     /// <summary>

src/Asynkron.JsEngine/JsEnvironment.cs

@@ -1001,16 +1001,6 @@ public bool HasVarDeclaration(Symbol name)
             return true;
         }
 
-        // For global scope, also check the global object for var declarations
-        if (IsGlobalFunctionScope)
-        {
-            var globalObject = GetRootGlobalObject();
-            if (globalObject is not null && globalObject.GetOwnPropertyDescriptor(name.Name) is not null)
-            {
-                return true;
-            }
-        }
-
         return false;
     }
 

src/Asynkron.JsEngine/Runtime/JsOps.cs

@@ -1626,6 +1626,11 @@ public static bool TryGetPropertyValue(object? target, object? propertyKey, out
 
     public static bool IsConstructor(object? value)
     {
+        if (value is JsProxy proxy)
+        {
+            return IsConstructor(proxy.Target);
+        }
+
         if (value is HostFunction host)
         {
             return host is { IsConstructor: true, DisallowConstruct: false };

src/Asynkron.JsEngine/StdLib/StandardLibrary.TypedArray.cs

@@ -547,6 +547,15 @@ private static HostFunction CreateTypedArrayConstructor<T>(
         constructor.SetProperty("BYTES_PER_ELEMENT", (double)bytesPerElement);
         prototype.SetPrototype(realm.ObjectPrototype);
         prototype.SetProperty("constructor", constructor);
+        var toStringTagKey = $"@@symbol:{TypedAstSymbol.For("Symbol.toStringTag").GetHashCode()}";
+        prototype.DefineProperty(toStringTagKey,
+            new PropertyDescriptor
+            {
+                Value = constructorName,
+                Writable = false,
+                Enumerable = false,
+                Configurable = true
+            });
         constructor.DefineProperty("name",
             new PropertyDescriptor
             {