Re: Bizarre missing changes (git bug?)

From: Jakub Narebski <jnareb@gmail.com>
Date: Jul 30, 2008, 08:36 UTC
Message-ID: <m3iqunu5u3.fsf@localhost.localdomain>
In-Reply-To: <Pine.LNX.4.64.0807291433430.6791@localhost.localdomain>

Roman Zippel <zippel@linux-m68k.org> writes:

Show 8 quoted lines

> I don't quite understand what you're trying to say.
> To avoid further confusion it maybe helps to specify a few of the terms:
> 
> - full history graph: produced by "git-log --full-history --parents"
> - compact history graph: the full history graph without without any 
>   repeated merges, this is what my example script produces.
> - full simplified history: output of "git-log --full-history"
> - short simplified history: standard output of "git-log"

[...]

> Keep in mind that e.g. git-web is using the full simplified history, so 
> what I'm offering also has the potential to improve git-web performance...

The fact that gitweb is using --full-history for a 'history' view is a historical reason, backwards compatibility with the view that was shown before gitweb used "git rev-list [flags] -- <path>", see commit cdd4037d

    gitweb: optimize per-file history generation
    
    The rev-list command that is recent enough can filter commits
    based on paths they touch, so use it instead of generating the
    full list and limiting it by passing it with diff-tree --stdin.
    
    [jc: The patch originally came from Luben Tuikov but the it was
     corrupt, but it was short enough to be applied by hand.  I
     added the --full-history to make the output compatible with the
     original while doing so.]
    
    Signed-off-by: Junio C Hamano <junkio@cox.net>

Removing '--parents' was put later, to remove unnecessary merges from a view (there was long discussion on git mailing list about --full-history with and without --parents), in 208b2dff

    gitweb: We do longer need the --parents flag in rev-list.
    
    We only want to know the direct parents of a given commit object,
    these parents are available in the --header output of rev-list.  If
    --parents is supplied with --full-history the output includes merge
    commits that aren't relevant.
    
    Signed-off-by: Robert Fitzsimons <robfitz@273k.net>
    Signed-off-by: Junio C Hamano <junkio@cox.net>

Besides gitweb currently does not generate graphical history view, so '--parents' are unnecessary.

But if it was done from the scratch, gitweb should definitely use simplified history, instead of what you call "full simplified history", perhaps with an option to use '--full-history' (there is infractructure in gitweb for adding extra options).

(Nitpick: it is 'gitweb', not 'git-web'.)

-- 
Jakub Narebski
Poland
ShadeHawk on #git