Propagate not-found on proxy target to GetRealNamedProperty

BUG=v8:4932
LOG=n

Review-Url: https://codereview.chromium.org/1929853002
Cr-Commit-Position: refs/heads/master@{#35846}

src/objects.cc

@@ -720,9 +720,14 @@ MaybeHandle<Object> Object::GetProperty(LookupIterator* it) {
       case LookupIterator::NOT_FOUND:
       case LookupIterator::TRANSITION:
         UNREACHABLE();
-      case LookupIterator::JSPROXY:
-        return JSProxy::GetProperty(it->isolate(), it->GetHolder<JSProxy>(),
-                                    it->GetName(), it->GetReceiver());
+      case LookupIterator::JSPROXY: {
+        bool was_found;
+        MaybeHandle<Object> result =
+            JSProxy::GetProperty(it->isolate(), it->GetHolder<JSProxy>(),
+                                 it->GetName(), it->GetReceiver(), &was_found);
+        if (!was_found) it->NotFound();
+        return result;
+      }
       case LookupIterator::INTERCEPTOR: {
         bool done;
         Handle<Object> result;
@@ -762,7 +767,9 @@ MaybeHandle<Object> Object::GetProperty(LookupIterator* it) {
 MaybeHandle<Object> JSProxy::GetProperty(Isolate* isolate,
                                          Handle<JSProxy> proxy,
                                          Handle<Name> name,
-                                         Handle<Object> receiver) {
+                                         Handle<Object> receiver,
+                                         bool* was_found) {
+  *was_found = true;
   if (receiver->IsJSGlobalObject()) {
     THROW_NEW_ERROR(
         isolate,
@@ -795,7 +802,9 @@ MaybeHandle<Object> JSProxy::GetProperty(Isolate* isolate,
     // 7.a Return target.[[Get]](P, Receiver).
     LookupIterator it =
         LookupIterator::PropertyOrElement(isolate, receiver, name, target);
-    return Object::GetProperty(&it);
+    MaybeHandle<Object> result = Object::GetProperty(&it);
+    *was_found = it.IsFound();
+    return result;
   }
   // 8. Let trapResult be ? Call(trap, handler, «target, P, Receiver»).
   Handle<Object> trap_result;

src/objects.h

@@ -9682,7 +9682,7 @@ class JSProxy: public JSReceiver {
   // ES6 9.5.8
   MUST_USE_RESULT static MaybeHandle<Object> GetProperty(
       Isolate* isolate, Handle<JSProxy> proxy, Handle<Name> name,
-      Handle<Object> receiver);
+      Handle<Object> receiver, bool* was_found);
 
   // ES6 9.5.9
   MUST_USE_RESULT static Maybe<bool> SetProperty(Handle<JSProxy> proxy,

test/cctest/test-api.cc

@@ -12870,6 +12870,19 @@ THREADED_TEST(VariousGetPropertiesAndThrowingCallbacks) {
   CHECK(try_catch.HasCaught());
   try_catch.Reset();
   CHECK(result.IsEmpty());
+
+  Local<Object> target = CompileRun("({})").As<Object>();
+  Local<Object> handler = CompileRun("({})").As<Object>();
+  Local<v8::Proxy> proxy =
+      v8::Proxy::New(context.local(), target, handler).ToLocalChecked();
+
+  result = target->GetRealNamedProperty(context.local(), v8_str("f"));
+  CHECK(!try_catch.HasCaught());
+  CHECK(result.IsEmpty());
+
+  result = proxy->GetRealNamedProperty(context.local(), v8_str("f"));
+  CHECK(!try_catch.HasCaught());
+  CHECK(result.IsEmpty());
 }