[ESnext] Implement Object Rest

src/runtime/runtime-object.cc

Index: src/runtime/runtime-object.cc
diff --git a/src/runtime/runtime-object.cc b/src/runtime/runtime-object.cc
index 397ad6c383d2ae9b55418bc5f6e9a126528b0e47..f9f32465548ac0ff5b250c2d1a1b6d2cdac58d2e 100644
--- a/src/runtime/runtime-object.cc
+++ b/src/runtime/runtime-object.cc
@@ -776,7 +776,7 @@ RUNTIME_FUNCTION(Runtime_DefineGetterPropertyUnchecked) {
 
 RUNTIME_FUNCTION(Runtime_CopyDataProperties) {
   HandleScope scope(isolate);
-  DCHECK(args.length() == 2);
+  DCHECK_EQ(2, args.length());
   CONVERT_ARG_HANDLE_CHECKED(JSObject, target, 0);
   CONVERT_ARG_HANDLE_CHECKED(Object, source, 1);
 
@@ -785,12 +785,31 @@ RUNTIME_FUNCTION(Runtime_CopyDataProperties) {
     return isolate->heap()->undefined_value();
   }
 
-  MAYBE_RETURN(
-      JSReceiver::SetOrCopyDataProperties(isolate, target, source, false),
-      isolate->heap()->exception());
+  MAYBE_RETURN(JSReceiver::SetOrCopyDataProperties(
+                   isolate, target, source, MaybeHandle<JSArray>(), false),
+               isolate->heap()->exception());
   return isolate->heap()->undefined_value();
 }
 
+RUNTIME_FUNCTION(Runtime_CopyDataPropertiesWithExcludedProperties) {
+  HandleScope scope(isolate);
+  DCHECK_EQ(2, args.length());
+  CONVERT_ARG_HANDLE_CHECKED(Object, source, 0);
+  CONVERT_ARG_HANDLE_CHECKED(JSArray, excluded_properties, 1);

[adamk, 2017/01/10 23:22:56]

As discussed, I think it'd be simpler to just pass the excluded properties
directly to this function instead of an array.

+
+  // 2. If source is undefined or null, let keys be an empty List.
+  if (source->IsUndefined(isolate) || source->IsNull(isolate)) {
+    return isolate->heap()->undefined_value();
+  }
+
+  Handle<JSObject> target =
+      isolate->factory()->NewJSObject(isolate->object_function());
+  MAYBE_RETURN(JSReceiver::SetOrCopyDataProperties(isolate, target, source,
+                                                   excluded_properties, false),
+               isolate->heap()->exception());
+  return *target;
+}
+
 RUNTIME_FUNCTION(Runtime_DefineSetterPropertyUnchecked) {
   HandleScope scope(isolate);
   DCHECK_EQ(4, args.length());