git svn fetch --localtime produces wrong commit times

git svn fetch --localtime produces wrong commit times

[Urs Thuermann]

In converting a SVN repository to git, the commit timestamp is
generated incorrectly.  I use "git svn fetch --localtime" and the
offset from UTC is always set to +0200 (probably because that is the
current local offset here, i.e. Europe/Berlin) even for times when it
should be +0100.

For example, in my SVN working copy I get

    $ svn log -r152
    ------------------------------------------------------------------------
    r152 | urs | 2010-08-16 11:05:52 +0200 (Mon, 16 Aug 2010) | 2 lines

    Add error checks on input file streams

    ------------------------------------------------------------------------
    $ svn log -r158
    ------------------------------------------------------------------------
    r158 | urs | 2010-11-24 00:24:13 +0100 (Wed, 24 Nov 2010) | 16 lines

    Make code portable to Linux/amd64

After converting to git using

    $ mkdir use
    $ cd use
    $ git svn init -s file://$HOME/SVN/use
    Initialized empty Git repository in /home/urs/GIT/use/.git/
    $ git svn fetch -q -A ../ADM/git.svn-authors --localtime
    r1 = 12cb83315be96e594a98b42db7ae57d19e0c7973 (refs/remotes/origin/trunk)
    ...
    r162 = 99ff393f1d64f330b14d6e06412b94fd3023d616 (refs/remotes/origin/trunk)
    Checked out HEAD:
      file:///home/urs/SVN/use/trunk r162

I see wrong commit timestamps:

    $ git log
    ...
    commit c6b4f7aaa66650a16de67d32fb83d541b1973331
    Author: Urs Thuermann <urs@isnogud.escape.de>
    Date:   Wed Nov 24 00:24:13 2010 +0200

        Make code portable to Linux/amd64


        git-svn-id: file:///home/urs/SVN/use/trunk@158 b3714422-7cff-11dd-9a33-b89007e0d947
    ...
    commit a9d95e506681ac5742d2d0927c93f22c541ff170
    Author: Urs Thuermann <urs@isnogud.escape.de>
    Date:   Mon Aug 16 11:05:52 2010 +0200

        Add error checks on input file streams


        git-svn-id: file:///home/urs/SVN/use/trunk@152 b3714422-7cff-11dd-9a33-b89007e0d947
    ...

In revision 152 the timestamp is correct, but for revision 158 the UTC
offset is +0200 instead of +0100.  Then, of course, also the POSIX
timestamp in the commit object is wrong:

    $ git cat-file -p c6b4f7aaa66650a16de67d32fb83d541b1973331
    tree ff4528220ddcf8beca9f4958fbb947d5ed85808e
    parent edcaeb292153663664d850bafe1dad12daab4165
    author Urs Thuermann <urs@isnogud.escape.de> 1290551053 +0200
    committer Urs Thuermann <urs@isnogud.escape.de> 1290551053 +0200

        Make code portable to Linux/amd64
    ...
    $ date -d@1290551053 +%F\ %T\ %z
    2010-11-23 23:24:13 +0100

The correct timestamp would be 2010-11-24 00:24:13 +0100, or, as a
POSIX time_t 1290554653.

I could find the bug grepping through /usr/lib/git-core/git-svn, maybe
it's in GIT::SVN::Fetcher or some other GIT::SVN module.

Is a fix available for this bug?

urs

Re: git svn fetch --localtime produces wrong commit times

[Urs Thuermann]

Urs Thuermann <urs@isnogud.escape.de> writes:

> I could find the bug grepping through /usr/lib/git-core/git-svn, maybe
> it's in GIT::SVN::Fetcher or some other GIT::SVN module.

Oops, that should be "could *not* find", of course.

urs

[PATCH] git svn fetch: Create correct commit timestamp when using --localtime

[Urs Thuermann]

In parse_svn_date() prepend the correct UTC offset to the timestamp
returned.  This is the offset in effect at the commit time instead of
the offset in effect at calling time.

Signed-off-by: Urs Thuermann <urs@isnogud.escape.de>
---
 perl/Git/SVN.pm | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/perl/Git/SVN.pm b/perl/Git/SVN.pm
index 98518f4..bc4eed3 100644
--- a/perl/Git/SVN.pm
+++ b/perl/Git/SVN.pm
@@ -1416,7 +1416,7 @@ sub parse_svn_date {
 			delete $ENV{TZ};
 		}
 
-		my $our_TZ = get_tz_offset();
+		my $our_TZ = get_tz_offset($epoch_in_UTC);
 
 		# This converts $epoch_in_UTC into our local timezone.
 		my ($sec, $min, $hour, $mday, $mon, $year,
-- 
2.1.4

Re: [PATCH] git svn fetch: Create correct commit timestamp when using --localtime

[Junio C Hamano]

Urs Thuermann <urs@isnogud.escape.de> writes:

> In parse_svn_date() prepend the correct UTC offset to the timestamp
> returned.  This is the offset in effect at the commit time instead of
> the offset in effect at calling time.
>
> Signed-off-by: Urs Thuermann <urs@isnogud.escape.de>
> ---
>  perl/Git/SVN.pm | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Thanks; sounds sensible.  

Eric?

>
> diff --git a/perl/Git/SVN.pm b/perl/Git/SVN.pm
> index 98518f4..bc4eed3 100644
> --- a/perl/Git/SVN.pm
> +++ b/perl/Git/SVN.pm
> @@ -1416,7 +1416,7 @@ sub parse_svn_date {
>  			delete $ENV{TZ};
>  		}
>  
> -		my $our_TZ = get_tz_offset();
> +		my $our_TZ = get_tz_offset($epoch_in_UTC);
>  
>  		# This converts $epoch_in_UTC into our local timezone.
>  		my ($sec, $min, $hour, $mday, $mon, $year,

Re: [PATCH] git svn fetch: Create correct commit timestamp when using --localtime

[Eric Wong]

Junio C Hamano <gitster@pobox.com> wrote:
> Urs Thuermann <urs@isnogud.escape.de> writes:
> 
> > In parse_svn_date() prepend the correct UTC offset to the timestamp
> > returned.  This is the offset in effect at the commit time instead of
> > the offset in effect at calling time.
> >
> > Signed-off-by: Urs Thuermann <urs@isnogud.escape.de>
> > ---
> >  perl/Git/SVN.pm | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> Thanks; sounds sensible.  
> 
> Eric?

Yep, seems alright.  Can you apply directly?
Been a bit preoccupied as of late.  Thanks.

Re: [PATCH] git svn fetch: Create correct commit timestamp when using --localtime

[Junio C Hamano]

Eric Wong <e@80x24.org> writes:

> Junio C Hamano <gitster@pobox.com> wrote:
>> Urs Thuermann <urs@isnogud.escape.de> writes:
>> 
>> > In parse_svn_date() prepend the correct UTC offset to the timestamp
>> > returned.  This is the offset in effect at the commit time instead of
>> > the offset in effect at calling time.
>> >
>> > Signed-off-by: Urs Thuermann <urs@isnogud.escape.de>
>> > ---
>> >  perl/Git/SVN.pm | 2 +-
>> >  1 file changed, 1 insertion(+), 1 deletion(-)
>> 
>> Thanks; sounds sensible.  
>> 
>> Eric?
>
> Yep, seems alright.  Can you apply directly?
> Been a bit preoccupied as of late.  Thanks.

Surely, I'll just add your Reviewed-by: myself ;-)

Thanks.

Re: [PATCH] git svn fetch: Create correct commit timestamp when using --localtime

[Urs Thuermann]

Junio C Hamano <gitster@pobox.com> writes:

> > Yep, seems alright.  Can you apply directly?
> > Been a bit preoccupied as of late.  Thanks.
> 
> Surely, I'll just add your Reviewed-by: myself ;-)

OK, thanks.  This will fix the bug I've reported here a week or so ago
(see the References header).

urs