Branch: refs/heads/main
Home: https://github.com/WebKit/WebKit
Commit: a011564b98ab104896256b0aaffd3ecb254d744a
https://github.com/WebKit/WebKit/commit/a011564b98ab104896256b0aaffd3ecb254d744a
Author: Sosuke Suzuki <[email protected]>
Date: 2026-08-05 (Wed, 05 Aug 2026)
Changed paths:
A JSTests/stress/array-sort-default-comparator-stability.js
M Source/JavaScriptCore/runtime/ArrayPrototype.cpp
Log Message:
-----------
[JSC] `Array#sort` without a comparator is not stable
https://bugs.webkit.org/show_bug.cgi?id=320982
Reviewed by Yusuke Suzuki.
The no-comparator string sort falls back to std::ranges::sort for buckets
smaller
than 32 entries and past the depth cap, and std::ranges::sort is not stable. The
default sort compares ToString results, which is a consistent comparator, so the
spec requires the result to be stable [1]:
let objects = [];
for (let i = 0; i < 30; ++i)
objects.push({ id: i, toString() { return "k" + (i % 3); } });
objects.sort(); // equal keys must keep their original order
Use std::ranges::stable_sort instead.
[1]: https://tc39.es/ecma262/#sec-sortindexedproperties
Test: JSTests/stress/array-sort-default-comparator-stability.js
* JSTests/stress/array-sort-default-comparator-stability.js: Added.
(shouldBe):
(makeEntries):
(verifyStable):
* Source/JavaScriptCore/runtime/ArrayPrototype.cpp:
(JSC::sortBucketSort):
Canonical link: https://commits.webkit.org/318682@main
To unsubscribe from these emails, change your notification settings at
https://github.com/WebKit/WebKit/settings/notifications
