Bug 218604

Summary:	[JSC] Make a bit more consistent for local time parsing
Product:	WebKit	Reporter:	Yusuke Suzuki <ysuzuki>
Component:	JavaScriptCore	Assignee:	Yusuke Suzuki <ysuzuki>
Status:	NEW ---
Severity:	Normal	CC:	webkit-bug-importer
Priority:	P2	Keywords:	InRadar
Version:	WebKit Nightly Build
Hardware:	Unspecified
OS:	Unspecified
See Also:	https://bugs.webkit.org/show_bug.cgi?id=161623

Description Yusuke Suzuki 2020-11-05 01:00:52 PST

(In reply to Joren Broekema from comment #9)
> I looked a bit further.
> https://en.wikipedia.org/wiki/Daylight_saving_time#History gives some
> background on why this is happening for certain years. Also, I don't think
> Intl is at fault, I have issues with the native Date parsing process
> 
> > new Date('1939-12-06')
> < Wed Dec 06 1939 01:00:00 GMT+0100 (CET)
> 
> > new Date('12/06/1939')
> < Wed Dec 06 1939 00:00:00 GMT+0100 (CET)
> 
> So it parses it differently based on how you supply the date string.

This is different issue from this bug. I think one format is parsed as local time, an the other is parsed UTC.

Comment 1 Yusuke Suzuki 2020-11-05 01:03:56 PST

We should get rid of wtf/DateMath.h's local time calculation. This should be done through icu::TimeZone's cache.

Comment 2 Radar WebKit Bug Importer 2020-11-12 01:01:20 PST

<rdar://problem/71317850>