177813 2017-10-03 07:22:19 -0700 RegExp non-standard properties are inconsistent with other browsers 2022-02-06 13:34:39 -0800 1 1 1 Unclassified WebKit JavaScriptCore WebKit Nightly Build Unspecified Unspecified RESOLVED DUPLICATE 220233 InRadar P2 Normal --- 1 rbyers webkit-unassigned ashvayka benjamin cdumez msaboff webkit-bug-importer oldest_to_newest 1355805 0 rbyers 2017-10-03 07:22:19 -0700 The non-standard properties on RegExp (eg. lastMatch, lastParen, leftContext, rightContext) are data properties in Safari, but accessor properties in current versions of Chrome, Firefox and Edge. Here's a simple repro: http://output.jsbin.com/yubojom On Chrome, Edge and Firefox it prints: RegExp.lastMatch: get,set,enumerable,configurable RegExp.lastParen: get,set,enumerable,configurable RegExp.leftContext: get,set,enumerable,configurable RegExp.rightContext: get,set,enumerable,configurable On Safari it prints: RegExp.lastMatch: value,writable,enumerable,configurable RegExp.lastParen: value,writable,enumerable,configurable RegExp.leftContext: value,writable,enumerable,configurable RegExp.rightContext: value,writable,enumerable,configurable Unfortunately, despite being widely supported, these APIs do not appear to be standardized (https://tc39.github.io/ecma262/#sec-regexp-constructor). The difference is unlikely to matter much in practice, but in theory it could cause interop issue. One specific (though rather special) example is here: https://github.com/GoogleChrome/confluence/issues/202. If it's trivial for JSC to change to match the other JS engines, perhaps it's worth doing? 1355806 1 rbyers 2017-10-03 07:27:50 -0700 Sorry, correction. They're data accessors on Edge 15 as well, they're just writable=true where safari is writable=false. 1357965 2 webkit-bug-importer 2017-10-07 16:07:34 -0700 <rdar://problem/34873681> 1837942 3 ashvayka 2022-02-06 13:34:39 -0800 (In reply to Rick Byers from comment #0) > Unfortunately, despite being widely supported, these APIs do not appear to > be standardized (https://tc39.github.io/ecma262/#sec-regexp-constructor). > The difference is unlikely to matter much in practice, but in theory it > could cause interop issue. One specific (though rather special) example is > here: https://github.com/GoogleChrome/confluence/issues/202. If it's > trivial for JSC to change to match the other JS engines, perhaps it's worth > doing? Thanks for the report. These APIs are now being standardized (https://github.com/tc39/proposal-regexp-legacy-features) as an accessors, and were implemented as such in r280460. *** This bug has been marked as a duplicate of bug 220233 ***