[modules] Basic support of exports

src/api.cc

Index: src/api.cc
diff --git a/src/api.cc b/src/api.cc
index 8eb0f2d55c51f475f0d923400a0e40ef64d3ba0f..0e2c6d1af919b781220bf1948aa99a21766c48ab 100644
--- a/src/api.cc
+++ b/src/api.cc
@@ -1846,11 +1846,22 @@ MaybeLocal<Value> Script::Run(Local<Context> context) {
   i::TimerEventScope<i::TimerEventExecute> timer_scope(isolate);
   TRACE_EVENT_CALL_STATS_SCOPED(isolate, "v8", "V8.Execute");
   auto fun = i::Handle<i::JSFunction>::cast(Utils::OpenHandle(this));
-  i::Handle<i::Object> receiver = isolate->global_proxy();
+
+  i::Handle<i::Object> receiver;
   Local<Value> result;
-  has_pending_exception =
-      !ToLocal<Value>(i::Execution::Call(isolate, fun, receiver, 0, NULL),
-                      &result);
+
+  if (fun->shared()->scope_info()->scope_type() == i::MODULE_SCOPE) {
+    receiver = isolate->factory()->undefined_value();
+    i::Handle<i::Object> argv[] = {
+        handle(isolate->native_context()->current_module())};
+    has_pending_exception = !ToLocal<Value>(
+        i::Execution::Call(isolate, fun, receiver, 1, argv), &result);
+  } else {
+    receiver = isolate->global_proxy();
+    has_pending_exception = !ToLocal<Value>(
+        i::Execution::Call(isolate, fun, receiver, 0, nullptr), &result);
+  }
+
   RETURN_ON_FAILED_EXECUTION(Value);
   RETURN_ESCAPED(result);
 }
@@ -1991,7 +2002,34 @@ MaybeLocal<Script> ScriptCompiler::CompileModule(Local<Context> context,
   Local<UnboundScript> generic;
   if (!maybe.ToLocal(&generic)) return MaybeLocal<Script>();
   v8::Context::Scope scope(context);
-  return generic->BindToCurrentContext();
+  auto result = generic->BindToCurrentContext();
+
+  i::Isolate* i_isolate = reinterpret_cast<i::Isolate*>(isolate);
+  i::Handle<i::JSModule> module = i_isolate->factory()->NewJSModule();
+  // TODO(neis): Storing the module into the native context is a temporary hack
+  // to pass it to the Script::Run function.  This will be removed once we
+  // support modules in the API.
+  i_isolate->native_context()->set_current_module(*module);
+
+  i::Handle<i::SharedFunctionInfo> shared =
+      i::Handle<i::SharedFunctionInfo>::cast(Utils::OpenHandle(*generic));
+  i::Handle<i::FixedArray> regular_exports =
+      i::handle(shared->scope_info()->ModuleDescriptorInfo()->regular_exports(),
+                i_isolate);
+  // TODO(neis): This will create multiple cells for the same local variable if
+  // exported under multiple names, which is wrong but cannot be observed at the
+  // moment. This will be fixed by doing the full-fledged linking here once we
+  // get there.
+  for (int i = 0; i < regular_exports->length(); ++i) {
+    i::Handle<i::ModuleInfoEntry> entry =
+        i::handle(i::ModuleInfoEntry::cast(regular_exports->get(i)), i_isolate);
+    DCHECK(entry->import_name()->IsUndefined(i_isolate));
+    i::Handle<i::String> export_name =
+        handle(i::String::cast(entry->export_name()), i_isolate);
+    i::JSModule::CreateExport(module, export_name);
+  }
+
+  return result;
 }