From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-3.6 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI,T_DKIMWL_WL_MED shortcircuit=no autolearn=ham autolearn_force=no version=3.4.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id C3BFF1F403 for ; Mon, 18 Jun 2018 10:20:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933814AbeFRKUz (ORCPT ); Mon, 18 Jun 2018 06:20:55 -0400 Received: from smtp-out-2.talktalk.net ([62.24.135.66]:60299 "EHLO smtp-out-2.talktalk.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933748AbeFRKUw (ORCPT ); Mon, 18 Jun 2018 06:20:52 -0400 Received: from [192.168.2.201] ([92.22.19.223]) by smtp.talktalk.net with SMTP id UrHEfSEH1VlGZUrHFfRy1n; Mon, 18 Jun 2018 11:20:50 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=talktalk.net; s=cmr1711; t=1529317250; bh=Tu333dOM4XLrB80QxU1OJBf89rHcOK8JFaQoj0J5Ai4=; h=Reply-To:Subject:To:Cc:References:From:Date:In-Reply-To; b=cgAel89NYIJYGioyp9hKmkO5yZ4BSnaSb6b3wU1WYsUnpqDhhuBhLoqTpAsB64qUq 8nAAa7frFsA4NzIbhVZfGAWH/qjtgXeboVQE7voq2mxmuwB6HdcNyuZoQiMlwdpnWn ZWWTNE3IzayI8oV912tsg5bRrXdzaR/4bHl5Sybw= X-Originating-IP: [92.22.19.223] X-Spam: 0 X-OAuthority: v=2.3 cv=JcuSU3CV c=1 sm=1 tr=0 a=DH/r9e32v+C519lOzZJhbw==:117 a=DH/r9e32v+C519lOzZJhbw==:17 a=IkcTkHD0fZMA:10 a=o5e1znM9KG4ORYezr3gA:9 a=QEXdDO2ut3YA:10 Reply-To: phillip.wood@dunelm.org.uk Subject: Re: [PATCH v2] sequencer: do not squash 'reword' commits when we hit conflicts To: Johannes Schindelin , phillip.wood@dunelm.org.uk Cc: Elijah Newren , Eric Sunshine , ch , git@vger.kernel.org, gitster@pobox.com References: <20180617053703.19856-1-newren@gmail.com> From: Phillip Wood Message-ID: <0ead1e75-98e9-8357-3e8d-2ff2f3cc5cc0@talktalk.net> Date: Mon, 18 Jun 2018 11:20:47 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-GB Content-Transfer-Encoding: 7bit X-CMAE-Envelope: MS4wfBKr1V+x8BKZItal7CsTxhqUpgOwSO/wP3Rl+MNhglfgV2TeEjzcPP0bPfI08YsuIx1klnB15FF+jn9BWf2woehfd3fvI+9zU4CwVGPoDww0YZQL91dM aOTvedEvWtUSw+kw4C1MfKcydIW7D3VFUKQ4qGE+OpTdzorcdjmc+TRkj68VuuZNcNIxEyPBKBcinLGWz0L7VT0QZMmrROY4wLc4rJU18dlE+0LlJjcQ44hb lMgm0niXaWwIybOIJCOxUCDaWYSCxi/aQSmJYnChBFwfe/QQh5uImVULHVmtDZjKvk6gDM7BvVlrLrszjHedEp2a5bNDNJFudHac8KY54ydKRaPm7p02gDDV 0AJWCJoS3q5+CrHrOpjwGtm65iJStg== Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Hi Johannes On 17/06/18 20:28, Johannes Schindelin wrote: > Hi Phillip, > > On Sun, 17 Jun 2018, Phillip Wood wrote: > >> On 17/06/18 06:37, Elijah Newren wrote: >>> Ever since commit 18633e1a22 ("rebase -i: use the rebase--helper builtin", >>> 2017-02-09), when a commit marked as 'reword' in an interactive rebase >>> has conflicts and fails to apply, when the rebase is resumed that commit >>> will be squashed into its parent with its commit message taken. >>> >>> The issue can be understood better by looking at commit 56dc3ab04b >>> ("sequencer (rebase -i): implement the 'edit' command", 2017-01-02), which >>> introduced error_with_patch() for the edit command. For the edit command, >>> it needs to stop the rebase whether or not the patch applies cleanly. If >>> the patch does apply cleanly, then when it resumes it knows it needs to >>> amend all changes into the previous commit. If it does not apply cleanly, >>> then the changes should not be amended. Thus, it passes !res (success of >>> applying the 'edit' commit) to error_with_patch() for the to_amend flag. >>> >>> The problematic line of code actually came from commit 04efc8b57c >>> ("sequencer (rebase -i): implement the 'reword' command", 2017-01-02). >>> Note that to get to this point in the code: >>> * !!res (i.e. patch application failed) >>> * item->command < TODO_SQUASH >>> * item->command != TODO_EDIT >>> * !is_fixup(item->command) [i.e. not squash or fixup] >>> So that means this can only be a failed patch application that is either a >>> pick, revert, or reword. For any of those cases we want a new commit, so >>> we should not set the to_amend flag. >> >> Unfortunately I'm not sure it's that simple. Looking and do_pick() sometimes >> reword amends HEAD and sometimes it does not. In the "normal" case then the >> commit is picked and committed with '--edit'. However when fast-forwarding the >> code fast forwards to the commit to be reworded and then amends it. If the >> root commit is being reworded it takes the same code path. While these cases >> cannot fail with conflicts, it is possible for the user to cancel the commit >> or for them to fail due to collisions with untracked files. >> >> If I remember correctly the shell version always picks the commit and then >> calls 'git commit --amend' afterwards which is less efficient but consistent. >> >> I'm afraid I don't have a simple solution for fixing this, as currently >> pick_commits() does not know if the commit was called with AMEND_MSG, I guess >> that means adding some kind of flag for do_pick() to set. > > Oh, you're right, the fast-forwarding path would pose a problem. I think > there is an easy way to resolve this, though: in the case that we do want > to amend the to-be-reworded commit, we simply have to see whether HEAD > points to the very same commit mentioned in the `reword` command: That's clever, I think to get it to work for rewording the root commit, it will need to do something like comparing HEAD to squash-onto as well. > -- snip -- > diff --git a/sequencer.c b/sequencer.c > index 2dad7041960..99d33d4e063 100644 > --- a/sequencer.c > +++ b/sequencer.c > @@ -3691,10 +3691,22 @@ static int pick_commits(struct todo_list > *todo_list, struct replay_opts *opts) > intend_to_amend(); > return error_failed_squash(item->commit, opts, > item->arg_len, item->arg); > - } else if (res && is_rebase_i(opts) && item->commit) > + } else if (res && is_rebase_i(opts) && item->commit) { > + int to_amend = 0; > + > + if (item->command == TODO_REWORD) { > + struct object_id head; > + > + if (!get_oid("HEAD", &head) && > + !oidcmp(&item->commit->object.oid, > + &head)) > + to_amend = 1; > + } > + > return res | error_with_patch(item->commit, > item->arg, item->arg_len, opts, res, > - item->command == TODO_REWORD); > + to_amend); > + } > } else if (item->command == TODO_EXEC) { > char *end_of_arg = (char *)(item->arg + item->arg_len); > int saved = *end_of_arg; > -- snap -- > > Note that > > - this patch is only compile-tested, and > > - it is on top of my sequencer-shears branch thicket, so it might not > apply cleanly to master, and > > - it could probably use a comment what we are doing here (see whether we > wanted to amend a fast-forwarded commit). Yes that would be helpful for future readers I think. > > What do you think about this approach? I like it assuming it's easy to extend it to the 'reword the root commit' case Best Wishes Phillip > Dscho >