From: Junio C Hamano <gitster@pobox.com>
Date: Tue, 23 Aug 2011 18:20:59 GMT
Subject: Re: [PATCH 1/2] Prevent force-updating of the current branch
Message-ID: <7v39gsrnuc.fsf@alter.siamese.dyndns.org>
In-Reply-To: <1313876989-16328-2-git-send-email-conrad.irwin@gmail.com>

Conrad Irwin <conrad.irwin@gmail.com> writes:

> git branch -M <foo> <current-branch> could be used to change the branch
> to which HEAD points, without the necessary house-keeping that git reset
> normally does to make this operation sensible. It would leave the reflog
> in a confusing state (you would be warned when trying to read it) and
> had an apparently side-effect of staging the diff between <current branch>
> and <foo>.

The last two lines are redundant (it is "without the house-keeping of
reset"); I'll remove "and had an apparently...".

> git checkout -B <current branch> <foo> was also partly vulnerable to
> this bug; due to inconsistent pre-flight checks it would perform half of
> its task and then abort just before rewriting the branch. Again this
> manifested itself as the index file getting out-of-sync with HEAD.
>
> git checkout -f already guarded against this problem, and aborted with
> a fatal error.

I assume you mean "branch -f". I'll rewrite it so, and in the present
tense.

> git branch -M, git checkout -B and git branch -f now use the same checks
> before allowing a branch to be created. These prevent you from updating
> the current branch.

Looks good ;-). Also the patch looks good, too.

Thanks.