{"action":"created","issue":{"url":"https://api.github.com/repos/tc39/ecma262/issues/128","labels_url":"https://api.github.com/repos/tc39/ecma262/issues/128/labels{/name}","comments_url":"https://api.github.com/repos/tc39/ecma262/issues/128/comments","events_url":"https://api.github.com/repos/tc39/ecma262/issues/128/events","html_url":"https://github.com/tc39/ecma262/issues/128","id":113435187,"number":128,"title":"Unicode RegExp with index points trail surrogate in surrogate pair is not covered in the spec","user":{"login":"arai-a","id":6299746,"avatar_url":"https://avatars.githubusercontent.com/u/6299746?v=3","gravatar_id":"","url":"https://api.github.com/users/arai-a","html_url":"https://github.com/arai-a","followers_url":"https://api.github.com/users/arai-a/followers","following_url":"https://api.github.com/users/arai-a/following{/other_user}","gists_url":"https://api.github.com/users/arai-a/gists{/gist_id}","starred_url":"https://api.github.com/users/arai-a/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/arai-a/subscriptions","organizations_url":"https://api.github.com/users/arai-a/orgs","repos_url":"https://api.github.com/users/arai-a/repos","events_url":"https://api.github.com/users/arai-a/events{/privacy}","received_events_url":"https://api.github.com/users/arai-a/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/tc39/ecma262/labels/observable%20semantics%20delta","name":"observable semantics delta","color":"5319e7"}],"state":"closed","locked":false,"assignee":null,"milestone":null,"comments":11,"created_at":"2015-10-26T19:40:51Z","updated_at":"2015-11-27T09:49:48Z","closed_at":"2015-10-27T00:21:42Z","body":"Derived from https://bugzilla.mozilla.org/show_bug.cgi?id=1135377\r\n\r\nES6 [21.2.2.2](http://ecma-international.org/ecma-262/6.0/#sec-pattern) steps 2.1-2 don't cover the case when `index` points a trails surrogate of the surrogate pair in `str`.\r\n\r\nHere's testcase:\r\n```\r\nvar r = /\\uDC38/ug;\r\nr.lastIndex = 1;\r\nvar str = \"\\uD83D\\uDC38\";\r\nr.exec(str);\r\n```\r\n\r\n`r.lastIndex` points trail surrogate `\\uDC38` in `str`.   In step 2.1, `Unicode` is `true` and `Input` becomes a single element list with `U+1f438`.  So `listIndex` cannot point the trail surrogate character in step 2.2.\r\n"},"comment":{"url":"https://api.github.com/repos/tc39/ecma262/issues/comments/160098909","html_url":"https://github.com/tc39/ecma262/issues/128#issuecomment-160098909","issue_url":"https://api.github.com/repos/tc39/ecma262/issues/128","id":160098909,"user":{"login":"anba","id":1447066,"avatar_url":"https://avatars.githubusercontent.com/u/1447066?v=3","gravatar_id":"","url":"https://api.github.com/users/anba","html_url":"https://github.com/anba","followers_url":"https://api.github.com/users/anba/followers","following_url":"https://api.github.com/users/anba/following{/other_user}","gists_url":"https://api.github.com/users/anba/gists{/gist_id}","starred_url":"https://api.github.com/users/anba/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/anba/subscriptions","organizations_url":"https://api.github.com/users/anba/orgs","repos_url":"https://api.github.com/users/anba/repos","events_url":"https://api.github.com/users/anba/events{/privacy}","received_events_url":"https://api.github.com/users/anba/received_events","type":"User","site_admin":false},"created_at":"2015-11-27T09:49:48Z","updated_at":"2015-11-27T09:49:48Z","body":"@bterlson Can you re-open this issue? Thanks!"}}