Re: [PATCH] [BUG] Add a test to check git-prune does not throw away revs hidden by a graft.

From: Yann Dirson <ydirson@altern.org>
Date: May 18, 2006, 22:20 UTC
Message-ID: <20060518222045.GB6535@nowhere.earth>
In-Reply-To: <7viro3nh07.fsf@assigned-by-dhcp.cox.net>

On Thu, May 18, 2006 at 02:46:16PM -0700, Junio C Hamano wrote:

Show 13 quoted lines

> Linus Torvalds <torvalds@osdl.org> writes:
> 
> > Is it/does it?
> >
> > I'd assume that if you have a graft, you _want_ the history to be hidden 
> > and pruned. 
> >
> > That's how you'd drop history, if you wanted to do it on purpose.
> 
> I haven't looked at what the test does, but I think he is
> talking about the opposite.  fsck by design does not honor
> grafts, and if you grafted a history back to your true root
> commit, that "older" history will be lost.

I'm not sure I understand what you're saying. AFACT fsck does not ignore grafts: if a rev is not accessible from heads because of a graft, prune drops it, and fsck does not see a problem.

Linus, I understand your point, but the current situation is problematic: a graft does not get propagated by cg-clone (and I suppose not by git-clone or git-fetch either), so cloning a tree which has undergone such a pruning operation results in an incomplete clone (indeed it is how I met the problem). Since grafts are supposed to have local effect only (as far as I understand), I see it as a bad indication to have such a remote effect.

Maybe to make things safe, prune should by default consider both physical and grafted parents as accessible, and a flag could be added to get the current behaviour for people really knowing what they're doing ?

Best regards,

-- 
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