See https://github.com/tc39/proposal-relative-indexing-method/issues/41. rdar://72933608
Created attachment 418019 [details] proposed patch. Let's test this on the EWS first.
Created attachment 418067 [details] proposed patch.
Created attachment 418082 [details] patch for landing. Yusuke also told me offline that I should enable Options::useAtMethod for the tests instead. I've reworked the patch to apply that. Will wait for the EWS before landing.
Committed r271746: <https://trac.webkit.org/changeset/271746> All reviewed patches have been landed. Closing bug and clearing flags on attachment 418082 [details].