From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Rast Subject: [PATCH] pull: pull into void by fast-forwarding from empty tree Date: Thu, 20 Jun 2013 14:36:03 +0200 Message-ID: <45f6841746e5dcea03a97fc3ea24aef274728023.1371731513.git.trast@inf.ethz.ch> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: , Jeff King , Junio C Hamano To: =?UTF-8?q?Stefan=20Sch=C3=BC=C3=9Fler?= X-From: git-owner@vger.kernel.org Thu Jun 20 14:36:18 2013 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Upe65-0001hi-8k for gcvg-git-2@plane.gmane.org; Thu, 20 Jun 2013 14:36:17 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757532Ab3FTMgL convert rfc822-to-quoted-printable (ORCPT ); Thu, 20 Jun 2013 08:36:11 -0400 Received: from edge20.ethz.ch ([82.130.99.26]:42876 "EHLO edge20.ethz.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757442Ab3FTMgI (ORCPT ); Thu, 20 Jun 2013 08:36:08 -0400 Received: from CAS20.d.ethz.ch (172.31.51.110) by edge20.ethz.ch (82.130.99.26) with Microsoft SMTP Server (TLS) id 14.2.298.4; Thu, 20 Jun 2013 14:35:57 +0200 Received: from linux-k42r.v.cablecom.net (129.132.153.233) by CAS20.d.ethz.ch (172.31.51.110) with Microsoft SMTP Server (TLS) id 14.2.298.4; Thu, 20 Jun 2013 14:36:04 +0200 X-Mailer: git-send-email 1.8.3.1.664.gae9f72a X-Originating-IP: [129.132.153.233] Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: The logic for pulling into an unborn branch was originally designed to be used on a newly-initialized repository (d09e79c, git-pull: allow pulling into an empty repository, 2006-11-16). It thus did not initially deal with uncommitted changes in the unborn branch. The case of an _unstaged_ untracked file was fixed by by 4b3ffe5 (pull: do not clobber untracked files on initial pull, 2011-03-25). However, it still clobbered existing staged files, both when the file exists in the merged commit (it will be overwritten), and when it does not (it will be lost!). We fix this by doing a two-way merge, where the "current" side of the merge is an empty tree, and the "target" side is HEAD (already updated to FETCH_HEAD at this point). This amounts to claiming that all work in the index was done vs. an empty tree, and thus all content of the index is precious. Reported-by: Stefan Sch=C3=BC=C3=9Fler Signed-off-by: Thomas Rast --- Stefan Sch=C3=BC=C3=9Fler writes: > I think there's a bug in git pull. Doing a git pull in a fresh > repository without any commits removes files in the index. [...] Thanks for the bug report! git-pull.sh | 9 ++++++++- t/t5520-pull.sh | 24 ++++++++++++++++++++++++ 2 files changed, 32 insertions(+), 1 deletion(-) diff --git a/git-pull.sh b/git-pull.sh index 638aabb..1f84383 100755 --- a/git-pull.sh +++ b/git-pull.sh @@ -266,10 +266,17 @@ case "$merge_head" in ;; esac =20 +# Pulling into unborn branch: a shorthand for branching off +# FETCH_HEAD, for lazy typers. if test -z "$orig_head" then git update-ref -m "initial pull" HEAD $merge_head "$curr_head" && - git read-tree -m -u HEAD || exit 1 + # Two-way merge: we claim the index is based on an empty tree, + # and try to fast-forward to HEAD. This ensures we will not + # lose index/worktree changes that the user already made on + # the unborn branch. + empty_tree=3D4b825dc642cb6eb9a060e54bf8d69288fbee4904 + git read-tree -m -u $empty_tree HEAD || exit 1 exit fi =20 diff --git a/t/t5520-pull.sh b/t/t5520-pull.sh index 6af6c63..927903c 100755 --- a/t/t5520-pull.sh +++ b/t/t5520-pull.sh @@ -57,6 +57,30 @@ test_expect_success 'pulling into void does not over= write untracked files' ' ) ' =20 +test_expect_success 'pulling into void does not overwrite staged files= ' ' + git init cloned-staged-colliding && + ( + cd cloned-staged-colliding && + echo "alternate content" >file && + git add file && + test_must_fail git pull .. master && + echo "alternate content" >expect && + test_cmp expect file + ) +' + +test_expect_success 'pulling into void does not remove new staged file= s' ' + git init cloned-staged-new && + ( + cd cloned-staged-new && + echo "new tracked file" >newfile && + git add newfile && + git pull .. master && + echo "new tracked file" >expect && + test_cmp expect newfile + ) +' + test_expect_success 'test . as a remote' ' =20 git branch copy master && --=20 1.8.3.1.664.gae9f72a