On 4 Aug 2013, at 01:17, Felipe Contreras <felipe.contre...@gmail.com> wrote:
> On Sat, Aug 3, 2013 at 11:36 AM, Jörn Hees <d...@joernhees.de> wrote:
>> it seems that if you use the remote-helpers/git-remote-hg to clone a 
>> mercurial repo the timezone information of commits gets transformed into 
>> your current timezone.
>> (command: git clone hg::…)
>> I noticed this when a colleague in another timezone used Kiln to also export 
>> the same mercurial repo that i had cloned from git before.
>> Fetching from his git repo gives me a "second root tree" with all commits 
>> duplicated.
>> A git show of two equivalent commit reveals that the Date: line of the 
>> commits changed.
>> Tracking this back into the original mercurial repo reveals that _his_ times 
>> are correct.
>> This will also make two or more clones from different timezones all using 
>> the same hg remote repo incompatible!
>> Example:
>> Original mercurial commit (timezone: -7200 = -4h)
>> https://bitbucket.org/lipis/gae-init/commits/a43078f90e727a13767cf14c740157763fb423b5/raw/

sorry, i feel stupid for this now… this obviously is -2h:  2*60*60… not 4
(but see below)

>> Lipis git export via Kiln: (-4h)
>> https://github.com/lipis/gae-init/commit/36b7cabf03fbba784cc41b63430433e9fc79ca8c

so is this: it should've said -2h

>> My export via git clone hg::ssh://h...@bitbucket.org/lipis/gae-init (+2h)
>> https://github.com/joernhees/git-hg-remote-bug_gae-init/commit/8341bf10f1f0a7a924717a8a2c1770f61acd51ae

this one was correct: +2h

> Actually our version is the correct one:
> % hg commit -m one -d "2012-04-28 11:28 +0200"
> % hg export
> # HG changeset patch
> # User Felipe Contreras <felipe.contre...@gmail.com>
> # Date 1335605280 -7200
> #      Sat Apr 28 11:28:00 2012 +0200

Thanks for clarifying this. I had falsely assumed that no one would dare to 
flip the sign of the timezone spec.
Turns out that mercurial commits contain the _negative_ timezone offset in 
seconds, so UTC+2 will actually be saved as -7200!
I was actually still doubtful so i searched for some credible ref and was able 
to find this insanity documented in "hg help dates":
> - "1165432709 0" (Wed Dec 6 13:18:29 2006 UTC)
>     This is the internal representation format for dates. The first number is
>     the number of seconds since the epoch (1970-01-01 00:00 UTC). The second
>     is the offset of the local timezone, in seconds west of UTC (negative if
>     the timezone is east of UTC).
I use the word insane here, as there are many standards for date times, but not 
one dares to switch the timezone sign!

I'm sorry for reporting this as a bug and instead have to pull my hat.


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