From:  Jason Orendorff <jorendorff@mozilla.com>
Date:  15 Jun 2016 16:35:35 Hong Kong Time
Newsgroup:  news.mozilla.org/mozilla.dev.tech.js-engine.internals
Subject:  

Re: Improving Date.parse

NNTP-Posting-Host:  63.245.214.181

On Thu, Jun 9, 2016 at 10:09 PM, Jim Blandy  wrote:

> The more I think about this, the more I'm coming around to Shaver's
> position. The volume of code on the web is such that it's not a bad first
> approximation to just think of it as a complete cover of every observable
> behavior the APIs exhibit. And so much of it is poorly maintained, or not
> actively maintained at all. So changing anything at all is just guaranteed
> to break things that will never get fixed.
>

All truisms but to show what a gray area we live in: we have already
changed Date parsing to improve compatibility, once to add ISO support (in
the ES5 era) and again very recently to support a few V8 quirks. No
complaints AFAIK.

Certainly if we think this change fixes more bugs than it will cause,
there's no reason not to change. The question is, during the development of
the web as it is now, were there more developers who weren't testing in
Firefox, or who wrote sniffing JS to shunt us into custom Firefox-only
parsing code that uses Firefox-specific quirks that are *not* supported in
the proposed standard?

-j