Bug #63777 [Nab]: DateTime obj in Dec 2012 in Australia/South TZ reports 'CST' time zone abbrev

Edit report at https://bugs.php.net/bug.php?id=63777&edit=1 ID: 63777 Updated by: rasmus@php.net Reported by: kavi at postpro dot net Summary: DateTime obj in Dec 2012 in Australia/South TZ reports 'CST' time zone abbrev Status: Not a bug Type: Bug Package: Date/time related Operating System: OS X, CentOS, Debian PHP Version: Irrelevant Block user comment: N Private report: N New Comment: Ok, it is truly not a bug. According to Olson it is CST in Adelaide now. Google, Wolfram and PHP are all in agreement here. Even that timeanddate.com page states right on it that: DST ends on Sunday, April 7, 2013 at 3:00 AM local daylight time DST starts on Sunday, October 6, 2013 at 2:00 AM local standard time So surely they should be showing DST right now. The 'S' is supposed to standard for "Standard" but people tend to use "Summer" as well. Previous Comments: ------------------------------------------------------------------------ [2013-01-07 19:07:45] kavi at postpro dot net Forget the prefix (ACDT vs CDT) portion. Mirroring Olson is good. If it's summer time in Australia, what does the 'D' in Australian CDT stand for? The reason I bring this up is because I've researched online and there are a number of timekeeping and other sites which are in disagreement. From http://en.wikipedia.org/wiki/Time_in_Australia "The main DST zones are the following: (Australian) Central Daylight Time (CDT or ACDT) – UTC+10:30, in South Australia (Australian) Eastern Daylight Time (EDT or AEDT) – UTC+11, in New South Wales, the A.C.T., Victoria, and Tasmania. [...] Beginning in 2008, the start of DST in these states and in South Australia occurs on the first Sunday in October, and its end is on the first Sunday in April." According to this, DST-observing zones in Australia are currently observing DST during the Australian summer (whether it's called summer time or not) - so unless I have the meanings of 'S' and 'D' in CST/CDT incorrect, or I've otherwise reasoned incorrectly, this is still a bug. According to Wolfram Alpha (Checked just now, 7 January 2013) it is CST right now: https://www.wolframalpha.com/input/?i=current+time+in+Adelaide According to timeanddate.com (on 7 January 2013) it is CDT right now: http://www.timeanddate.com/worldclock/city.html?n=5 This does need attention, even if only to verify that it is truly not a bug. ------------------------------------------------------------------------ [2012-12-17 01:35:44] aharvey@php.net Unfortunately, as a Western Australian who's suffered through our state government's various flip-flops on daylight saving, I'm much more familiar with this than I want to be — the Olson database is technically correct here, as every state legislates or proclaims daylight saving time as "summer time", so the S part of the CST abbreviation is correct. Beyond that, I think that the Olson notes and related mailing list posts lay out the case for not prefixing the abbreviations reasonably well. Realistically, any change to this would need to happen upstream anyway — I doubt we want to start patching tzdata to differ from the mainline that almost everyone else deploys. ------------------------------------------------------------------------ [2012-12-15 04:38:26] rasmus@php.net Two things confuse me about this bug report. Surely it is summer in Australia right now, so why would you expect ACDT? And second, Olson has never used the 'A' prefix and as far as I know most places don't. There is a long discussion on this in the Olson australasia file. I'll leave this as an exercise for the interested to look up. If you go to Google and search for "time in Adelaide" you get a CST time just like PHP provides. ------------------------------------------------------------------------ [2012-12-15 04:17:30] sixd@php.net Testcase confirmed with 5.3, 5.4, 5.5 from git. All use Olson 2012.10 ------------------------------------------------------------------------ [2012-12-14 23:43:45] kavi at postpro dot net See #50276 for a tangentially related bug about the Australian timezone abbreviations. ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at https://bugs.php.net/bug.php?id=63777 -- Edit this bug report at https://bugs.php.net/bug.php?id=63777&edit=1