From: Nguyen Thai Ngoc Duy <pclouds@gmail.com>
Date: Sun, 05 Sep 2010 01:58:08 GMT
Subject: Re: [RFC PATCH 06/15] Automatically reuse sparse limiting arguments in revision walking
Message-ID: <AANLkTik1E=7Uawq-fGXppac3ur-oohq104A5wEgxv8cL@mail.gmail.com>
In-Reply-To: <1283645647-1891-7-git-send-email-newren@gmail.com>

On Sun, Sep 5, 2010 at 10:13 AM, Elijah Newren <newren@gmail.com> wrote:
> In a sparse repository, by automatically making use of sparse limits
> specified at clone time, we can avoid walking uninteresting commits and
> prevent access to missing trees and blobs.  Note that this means that if
> you created a sparse clone with
>  git clone <repo> <dest_dir> -- PATH1 PATH2 PATH3 PATH4 PATH5
> then
>  git log
> implicitly runs as though you had manually specified
>  git log -- PATH1 PATH2 PATH3 PATH4 PATH5
> Similarly, running
>  git diff
> implicitly runs as though you had manually specified
>  git diff -- PATH1 PATH2 PATH3 PATH4 PATH5
>
> This is necessary for proper operation of git diff in a sparse clone to
> avoid accessing missing objects.  In the case of a plain git log, this
> merely serves as an additional convenience, but for more complicated log
> operations (e.g. when passing -p or -S options) it becomes necessary.

I have a nicer approach here. Instead of modifying setup_revisions()
and similar functions, I update get_pathspec() to rewrite the
pathspecs from command line in narrow/shallow repos. get_pathspec()
currently does some form of rewriting already (prepending prefix).

So if you do "git log", get_pathspec() would return "git log -- PATH1
PATH2...". Will repost my series soon, or I can send that particular
patch to you.
-- 
Duy