Re: Something like $Id$, $Revision$ or $Date$?

From: Jakub Narebski <jnareb@gmail.com>
Date: Nov 10, 2008, 20:17 UTC
Message-ID: <200811102117.30372.jnareb@gmail.com>
In-Reply-To: <871vxjl5af.fsf@erwin.mina86.com>

Michal Nazarewicz wrote:

Show 25 quoted lines

> Jakub Narebski <jnareb@gmail.com> writes:
>> Dnia poniedziałek 10. listopada 2008 18:38, Michal Nazarewicz napisał:
>>> Jakub Narebski <jnareb@gmail.com> writes:
>>> 
>>>> The reason why git doesn't support keywords like $Revision$ or $Date$
>>>> is performance: the $Revision$ and $Date$ are keywords related to
>>>> _commit_ data, not blob data. 
>>> 
>>> In my case identifying content not commit would be even better.
>>
>> Well, in that case using `ident` attribute would be enough
>> (but cryptic).
> 
> Yes, but it forces me to do some voodoo magic (ie. checkout) to get the
> Id in the file, ;) like so:
> 
> #v+
> $ echo '$Id$'>bar && git add bar && git commit -m 'Added bar' && cat bar
> Created commit d49d436: Added bar
>  1 files changed, 1 insertions(+), 0 deletions(-)
>  create mode 100644 bar
> $Id$
> $ rm bar && git checkout bar && cat bar
> $Id: 055c8729cdcc372500a08db659c045e16c4409fb $
> #v-

Well, _some_ command has to be invoked to expand keywords. "git add" doesn't do that (perhaps it should?), so you need to use checkout.

And checkout doesn't touch file if it is identical, so you need to remove it first; nevertheless you don't need to use commit in betwen, as "git checkout bar" would checkout file out of index (you added contents of file to index with "git add bar").

-- 
Jakub Narebski
Poland