On Thu, Nov 27, 2014 at 10:35 AM, Dmitry Lomov <dslo...@chromium.org> wrote:
> > > On Thu, Nov 27, 2014 at 10:13 AM, Drew Wilson <atwil...@chromium.org> > wrote: > >> What impact do we expect on web compatibility from apps that may already >> be adding attributes named "include", etc to their String objects? >> >> I think that adding attributes that Firefox is already shipping should be >> relatively safe, but I'm very leery about being the first browser to add >> new attributes. What can we do to avoid a repeat of >> http://crbug.com/409858? Do we have any stats for how often these >> attributes are already in use in web pages (tricky, since some apps are >> legitimately using them for polyfill purposes)? >> > Correct, this is tricky. We do not have stats (and it is unclear how to > get those stats). > 'contains' was renamed to 'includes' precisely to reduce possible web > compat breakage. > Unfortunately we will not know of any breakage until we ship this - it has > been available under a flag for some time, but it looks like nobody tests > with 'Experimental Javascript features' enabled. > Therefore enabling it early on canary in Chrome 41 process is our best > mitigation in this particular case. > I'm not sure "let's just launch this and see who complains" is an acceptable path forward given that this specific approach was tried last release with Array.values and blew up in our face. Why do we think this time will be any different? Can we perhaps restrict this to canary + dev channel (and maybe the first beta cut), but hold off on shipping to Stable until we find a way to generate stats? Just making this change with no stats around conflicts would be like the blink team deprecating an API without first measuring how often it's used. > > Going forward, we have recently changed the definition of 'Experimental > Javascript fetaures' in Chrome to mean 'enable staged features' (per our > process https://developers.google.com/v8/launchprocess). > This means that this flag really enables only those features that we > consider quite mature, in particular they are expected to be stable and > implementation of them must be complete. > With that, we plan to evangelize enabling this flag among the power users, > so that we hear about any breakage early. > Can we set "enable staged features" for the Dev channel by default to increase usage? I don't actually think this will solve the problem since experience has shown us that not enough users run on that channel to catch all of the incompatibility issues, but at least it's a start. > > Dmitry > > > >> >> On Thu, Nov 27, 2014 at 9:27 AM, Dmitry Lomov <dslo...@chromium.org> >> wrote: >> >>> [FYI +blink-dev] >>> >>> ES6 extends String.prototype with several methods: repeat, startsWith, >>> endsWith, includes, codePointAt) and adds String.fromCodePoint method. >>> >>> Firefox ships codePointAt and fromCodePoint since release 29 [1], >>> startsWith and endsWith since release 17 [2], and repeat since release 24 >>> [3]. >>> >>> 'include' was previously named 'contains' and has been renamed at the >>> last TC39 meeting. Firefox shipped 'contains' since release 17. >>> >>> These methods has been available under a flag for a while, and were >>> staged in Chrome 40. >>> >>> [1] https://developer.mozilla.org/en-US/Firefox/Releases/29 >>> [2] https://developer.mozilla.org/en-US/Firefox/Releases/17 >>> [3] https://developer.mozilla.org/en-US/Firefox/Releases/24 >>> >>> Owners: yang...@chromium.org, dslo...@chromium.org >>> >> >> > -- -- v8-users mailing list v8-users@googlegroups.com http://groups.google.com/group/v8-users --- You received this message because you are subscribed to the Google Groups "v8-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to v8-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
