[modules] Basic support of exports

src/objects.cc

 // Copyright 2015 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 "src/objects.h"
 
 #include <cmath>
 #include <iomanip>
 #include <memory>
 #include <sstream>
@@ skipping 19325 matching lines @@
 
 bool JSReceiver::HasProxyInPrototype(Isolate* isolate) {
   for (PrototypeIterator iter(isolate, this, kStartAtReceiver,
                               PrototypeIterator::END_AT_NULL);
        !iter.IsAtEnd(); iter.AdvanceIgnoringProxies()) {
     if (iter.GetCurrent<Object>()->IsJSProxy()) return true;
   }
   return false;
 }
 
+void JSModule::CreateExport(Handle<JSModule> module, Handle<String> name) {
+  Isolate* isolate = module->GetIsolate();
+  Handle<Cell> cell =
+      isolate->factory()->NewCell(isolate->factory()->undefined_value());
+  LookupIterator it(module, name);
+  JSObject::CreateDataProperty(&it, cell, Object::THROW_ON_ERROR).ToChecked();
+}
+
+void JSModule::StoreExport(Handle<JSModule> module,
+                           Handle<String> name, Handle<Object> value) {
+  LookupIterator it(module, name);
+  Handle<Cell> cell = Handle<Cell>::cast(JSObject::GetDataProperty(&it));
+  cell->set_value(*value);
+}
+
+Handle<Object> JSModule::LoadExport(Handle<JSModule> module,
+                                    Handle<String> name) {
+  Isolate* isolate = module->GetIsolate();
+  LookupIterator it(module, name);
+  Handle<Cell> cell = Handle<Cell>::cast(JSObject::GetDataProperty(&it));
+  return handle(cell->value(), isolate);
+}
+
 }  // namespace internal
 }  // namespace v8