Re: [PATCH] reset --hard/read-tree --reset -u: remove unmerged new paths

From: Junio C Hamano <gitster@pobox.com>
Date: Oct 16, 2008, 14:49 UTC
Message-ID: <7v8wsok32m.fsf@gitster.siamese.dyndns.org>
In-Reply-To: <20081016072010.GA19188@elte.hu>

Ingo Molnar <mingo@elte.hu> writes:

> Does your fix mean that all i have to do in the future is a hard reset 
> back to HEAD, and that dangling files are not supposed to stay around?

As long as the index *somehow* knows about these new files, they are removed.

The situation is:

 (0) you start from a HEAD that does not have path xyzzy;
 (1) you attempt to merge a rev that has path xyzzy;
 (2) the merge conflicts, leaving higher staged index entries for the
     path.
 (3) you decide not to conclude the merge by saying "reset --hard".

The old logic for "reset" was to remove paths that exist in the index at stage #0 (i.e. cleanly merged) and not in HEAD. The patch changes the rule to remove paths that exist in the index at any stage (i.e. including the ones that have conflicted and not resolved yet) and not in HEAD.