[strong] Implement strong mode restrictions on property access

src/runtime/runtime-classes.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <stdlib.h>
 #include <limits>
 
 #include "src/v8.h"
 
 #include "src/arguments.h"
@@ skipping 102 matching lines @@
       prototype_parent = isolate->factory()->null_value();
     } else if (super_class->IsSpecFunction()) {
       if (Handle<JSFunction>::cast(super_class)->shared()->is_generator()) {
         THROW_NEW_ERROR_RETURN_FAILURE(
             isolate,
             NewTypeError(MessageTemplate::kExtendsValueGenerator, super_class));
       }
       ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
           isolate, prototype_parent,
           Runtime::GetObjectProperty(isolate, super_class,
-                                     isolate->factory()->prototype_string()));
+                                     isolate->factory()->prototype_string(),
+                                     Strength::WEAK));
       if (!prototype_parent->IsNull() && !prototype_parent->IsSpecObject()) {
         THROW_NEW_ERROR_RETURN_FAILURE(
             isolate, NewTypeError(MessageTemplate::kPrototypeParentNotAnObject,
                                   prototype_parent));
       }
       constructor_parent = super_class;
     } else {
       // TODO(arv): Should be IsConstructor.
       THROW_NEW_ERROR_RETURN_FAILURE(
           isolate,
@@ skipping 110 matching lines @@
     return isolate->ThrowIllegalOperation();
   }
 
   Handle<String> source(String::cast(Handle<Script>::cast(script)->source()));
   return *isolate->factory()->NewSubString(
       source, Handle<Smi>::cast(start_position)->value(),
       Handle<Smi>::cast(end_position)->value());
 }
 
 
-static Object* LoadFromSuper(Isolate* isolate, Handle<Object> receiver,
-                             Handle<JSObject> home_object, Handle<Name> name) {
+static MaybeHandle<Object> LoadFromSuper(Isolate* isolate,
+                                         Handle<Object> receiver,
+                                         Handle<JSObject> home_object,
+                                         Handle<Name> name,
+                                         LanguageMode language_mode) {
   if (home_object->IsAccessCheckNeeded() && !isolate->MayAccess(home_object)) {
     isolate->ReportFailedAccessCheck(home_object);
-    RETURN_FAILURE_IF_SCHEDULED_EXCEPTION(isolate);
+    RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
   }
 
   PrototypeIterator iter(isolate, home_object);
   Handle<Object> proto = PrototypeIterator::GetCurrent(iter);
-  if (!proto->IsJSReceiver()) return isolate->heap()->undefined_value();
+  if (!proto->IsJSReceiver()) {
+    return Object::ReadAbsentProperty(isolate, proto, name,
+                                      strength(language_mode));
+  }
 
   LookupIterator it(receiver, name, Handle<JSReceiver>::cast(proto));
   Handle<Object> result;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, Object::GetProperty(&it));
-  return *result;
+  ASSIGN_RETURN_ON_EXCEPTION(isolate, result,
+                             Object::GetProperty(&it, strength(language_mode)),
+                             Object);
+  return result;
 }
 
 
-static Object* LoadElementFromSuper(Isolate* isolate, Handle<Object> receiver,
-                                    Handle<JSObject> home_object,
-                                    uint32_t index) {
+static MaybeHandle<Object> LoadElementFromSuper(Isolate* isolate,
+                                                Handle<Object> receiver,
+                                                Handle<JSObject> home_object,
+                                                uint32_t index,
+                                                LanguageMode language_mode) {
   if (home_object->IsAccessCheckNeeded() && !isolate->MayAccess(home_object)) {
     isolate->ReportFailedAccessCheck(home_object);
-    RETURN_FAILURE_IF_SCHEDULED_EXCEPTION(isolate);
+    RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
   }
 
   PrototypeIterator iter(isolate, home_object);
   Handle<Object> proto = PrototypeIterator::GetCurrent(iter);
-  if (!proto->IsJSReceiver()) return isolate->heap()->undefined_value();
+  if (!proto->IsJSReceiver()) {
+    Handle<Object> name = isolate->factory()->NewNumberFromUint(index);
+    return Object::ReadAbsentProperty(isolate, proto, name,
+                                      strength(language_mode));
+  }
 
   LookupIterator it(isolate, receiver, index, Handle<JSReceiver>::cast(proto));
   Handle<Object> result;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, Object::GetProperty(&it));
-  return *result;
+  ASSIGN_RETURN_ON_EXCEPTION(isolate, result,
+                             Object::GetProperty(&it, strength(language_mode)),
+                             Object);
+  return result;
 }
 
 
 RUNTIME_FUNCTION(Runtime_LoadFromSuper) {
   HandleScope scope(isolate);
-  DCHECK(args.length() == 3);
+  DCHECK(args.length() == 4);
   CONVERT_ARG_HANDLE_CHECKED(Object, receiver, 0);
   CONVERT_ARG_HANDLE_CHECKED(JSObject, home_object, 1);
   CONVERT_ARG_HANDLE_CHECKED(Name, name, 2);
+  CONVERT_LANGUAGE_MODE_ARG_CHECKED(language_mode, 3);
 
-  return LoadFromSuper(isolate, receiver, home_object, name);
+  Handle<Object> result;
+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
+      isolate, result,
+      LoadFromSuper(isolate, receiver, home_object, name, language_mode));
+  return *result;
 }
 
 
 RUNTIME_FUNCTION(Runtime_LoadKeyedFromSuper) {
   HandleScope scope(isolate);
-  DCHECK(args.length() == 3);
+  DCHECK(args.length() == 4);
   CONVERT_ARG_HANDLE_CHECKED(Object, receiver, 0);
   CONVERT_ARG_HANDLE_CHECKED(JSObject, home_object, 1);
   CONVERT_ARG_HANDLE_CHECKED(Object, key, 2);
+  CONVERT_LANGUAGE_MODE_ARG_CHECKED(language_mode, 3);
 
   uint32_t index = 0;
+  Handle<Object> result;
+
   if (key->ToArrayIndex(&index)) {
-    return LoadElementFromSuper(isolate, receiver, home_object, index);
+    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
+        isolate, result, LoadElementFromSuper(isolate, receiver, home_object,
+                                              index, language_mode));
+    return *result;
   }
 
   Handle<Name> name;
   ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, name,
                                      Runtime::ToName(isolate, key));
   if (name->AsArrayIndex(&index)) {
-    return LoadElementFromSuper(isolate, receiver, home_object, index);
+    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
+        isolate, result, LoadElementFromSuper(isolate, receiver, home_object,
+                                              index, language_mode));
+    return *result;
   }
-  return LoadFromSuper(isolate, receiver, home_object, name);
+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
+      isolate, result,
+      LoadFromSuper(isolate, receiver, home_object, name, language_mode));
+  return *result;
 }
 
 
 static Object* StoreToSuper(Isolate* isolate, Handle<JSObject> home_object,
                             Handle<Object> receiver, Handle<Name> name,
                             Handle<Object> value, LanguageMode language_mode) {
   if (home_object->IsAccessCheckNeeded() && !isolate->MayAccess(home_object)) {
     isolate->ReportFailedAccessCheck(home_object);
     RETURN_FAILURE_IF_SCHEDULED_EXCEPTION(isolate);
   }
@@ skipping 123 matching lines @@
   return nullptr;
 }
 
 
 RUNTIME_FUNCTION(Runtime_CallSuperWithSpread) {
   UNIMPLEMENTED();
   return nullptr;
 }
 }  // namespace internal
 }  // namespace v8