Re: fetch: Auto-following tags should check connectivity, not existence

From: Junio C Hamano <junkio@cox.net>
Date: Apr 20, 2007, 06:39 UTC
Message-ID: <7v4pnb4kil.fsf@assigned-by-dhcp.cox.net>
In-Reply-To: <4624F183.D4B6BBB1@eudaptics.com>

Johannes Sixt <J.Sixt@eudaptics.com> writes:

Show 23 quoted lines

> git-fetch's auto-following of tags fetches all tags for which it finds
> objects in the local repository. I feel it were better if not object
> existence, but connectivity to the existing refs was checked, like this:
>
> diff --git a/git-fetch.sh b/git-fetch.sh
> index fd70696..1b3c459 100755
> --- a/git-fetch.sh
> +++ b/git-fetch.sh
> @@ -314,11 +314,12 @@ case "$no_tags$tags" in
>         taglist=$(IFS=' ' &&
>         echo "$ls_remote_result" |
>         git-show-ref --exclude-existing=refs/tags/ |
>         while read sha1 name
>         do
> -           git-cat-file -t "$sha1" >/dev/null 2>&1 || continue
> +           t=$(git-rev-list --max-count=1 "$sha1" --not --all 2>
> /dev/null) &&
> +           test -z "$t" || continue
>             echo >&2 "Auto-following $name"
>             echo ".${name}:${name}"
>         done)
>     esac
>     case "$taglist" in

I think "something like this" is a sensible thing to do, on top of the updates to "rev-list --objects" to verify the blob we list actually exists.

However, I think --max-count=1 defeats what you are trying to do. Revision limiting will only look at commits, and if you have all commits that lead to the "$sha1" commit from some of the existing refs, but lack some blobs or trees that belong to some of the commits that are not the first commit that will be listed, their absense will not be noticed.