Avoid 2 times name iteration in Object.assign
https://bugs.webkit.org/show_bug.cgi?id=147268
Reviewed by Geoffrey Garen.
Object.assign calls Object.getOwnPropertyNames & Object.getOwnPropertySymbols to collect all the names.
But exposing the private API that collects both at the same time makes the API efficient when the given Object has so many non-indexed properties.
Since Object.assign is so generic API (some form of utility API), the form of the given Object is not expected.
So the taken object may have so many non-indexed properties.
In this patch, we introduce `ownEnumerablePropertyKeys` private function.
It is minor changed version of `[[OwnPropertyKeys]]` in the ES6 spec;
It only includes enumerable properties.
By filtering out the non-enumerable properties in the exposed private function,
we avoid calling @objectGetOwnPropertyDescriptor for each property at the same time.
* builtins/ObjectConstructor.js:
(assign):
* runtime/CommonIdentifiers.h:
* runtime/EnumerationMode.h:
* runtime/JSGlobalObject.cpp:
(JSC::JSGlobalObject::init):
* runtime/ObjectConstructor.cpp:
(JSC::ownEnumerablePropertyKeys):
* runtime/ObjectConstructor.h:
* tests/stress/object-assign-enumerable.js: Added.
(shouldBe):
* tests/stress/object-assign-order.js: Added.
(shouldBe):
git-svn-id: http://svn.webkit.org/repository/webkit/trunk@187363 268f45cc-cd09-0410-ab3c-d52691b4dbfc
9 files changed
