From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-2.6 required=3.0 tests=AWL,BAYES_00, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, RCVD_IN_DNSWL_HI,T_RP_MATCHES_RCVD shortcircuit=no autolearn=no autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id EBEBA1F404 for ; Fri, 23 Feb 2018 12:38:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751440AbeBWMir (ORCPT ); Fri, 23 Feb 2018 07:38:47 -0500 Received: from mout.gmx.net ([212.227.17.20]:57739 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751332AbeBWMir (ORCPT ); Fri, 23 Feb 2018 07:38:47 -0500 Received: from [192.168.0.129] ([37.201.195.115]) by mail.gmx.com (mrgmx102 [212.227.17.168]) with ESMTPSA (Nemesis) id 0MN748-1en0lT2c6S-006brV; Fri, 23 Feb 2018 13:38:39 +0100 Date: Fri, 23 Feb 2018 13:38:24 +0100 (STD) From: Johannes Schindelin X-X-Sender: virtualbox@MININT-6BKU6QN.europe.corp.microsoft.com To: git@vger.kernel.org cc: Junio C Hamano , Jacob Keller , Stefan Beller , Philip Oakley , Eric Sunshine , Phillip Wood Subject: [PATCH v4 08/12] rebase: introduce the --recreate-merges option In-Reply-To: Message-ID: <31098ae586dcd2c5b08e3f7db1a99d1ccef64ed8.1519389319.git.johannes.schindelin@gmx.de> References: User-Agent: Alpine 2.21.1 (DEB 209 2017-03-23) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Provags-ID: V03:K0:3e3Y28vVO84XOYfzuaBkir9pXk0MyjPRVPeJgrETxpaajH3/clX 4dWi2zpJBgaPKiwP8iQmqkWz0mtjvUaJM1hnWsju/k0Vn33QJ6pB7tXgB4ErlcbtrMRKhVk xtXY8MpF1O+UtXBF4wxUtQJ7v2H3adu1qVURumRi9U3JdqtS0skVLdeX5BiJdFgUkHz0XmU z+s/G54QAdJJGIvJKGe4w== X-UI-Out-Filterresults: notjunk:1;V01:K0:wrzZSN7U3ic=:XFmukmTVljTsEwcmJdrTst 1g4S/v5Id/pNtyT5zaIOsVypcwjQIJH9SL4ALxGU8VM4yS/XvWSuRh21xeEtMbK07Fh1ecin2 zAiqaqEW39SGhRbMJ/HBP5NbVjCCIpqNpCxwhWvScBSa321zPGMcmymBc8S6itA6l50zwums6 d4SyxGGvPcezFv2nJaWmjECt5GBgI+TOXidBq1SRLcf2olNWDaM9YI09AwL0s2TfboGoYeu6d m4QJACTLXsXuA7ED7j2xPzWgOv+n5h3muLauT6RrEvJ9wy3B/9mJ30GXfoLuUrOpiYwPIBogV trddMzCfPLKf0cjyfm2T3lbnQNc7zWPTRoJPj93DkTx9qE+HEQtfC/plfUH+TkwzyDxsBU339 GYNoRUyVpeiNfrbqpoDwW4iqGoehbv9YFoUmNthK/SQUuFW0qt8ryxv1or4DI5TYK9u+SvS9l Du6V8xxLUi8KOL+bEmZFuy60KZzDy1JVuQeuPYbJqIqXRum0Z/XbSeGU5JoTPUcmNqStU7wum 3dkPhcjRUaRPIUNdT4UflOeMZmWY1y0XFhMBvRM2CEUKNjY6inyBSHr9S4UijDewNk8Ulx/M4 8RDuenYDh+edxXN/i7qH4lbd2fOtFbKVnHGD1a5LbSx27pJCn03x/8gpEGEFAy5xAI1eg6exs p0a5pa5cwRIwLimJOptCNdqAtoHpQUUxdYBWNOcTlROxxCuQBdsvpK6je3GkolQVWrdH22ZU1 p/PcfJgt1KUHwBpra2OH13s3Ijvv/Bf8aZJfZhQecmEmOJuajWQPBh1nuZ5E0qcPuRJjPCi3l fWN+jOqJkoZIPWF6TjaI6a9+NtgF4GFGiIXv3wETgMKGyo2HX8= Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Once upon a time, this here developer thought: wouldn't it be nice if, say, Git for Windows' patches on top of core Git could be represented as a thicket of branches, and be rebased on top of core Git in order to maintain a cherry-pick'able set of patch series? The original attempt to answer this was: git rebase --preserve-merges. However, that experiment was never intended as an interactive option, and it only piggy-backed on git rebase --interactive because that command's implementation looked already very, very familiar: it was designed by the same person who designed --preserve-merges: yours truly. Some time later, some other developer (I am looking at you, Andreas! ;-)) decided that it would be a good idea to allow --preserve-merges to be combined with --interactive (with caveats!) and the Git maintainer (well, the interim Git maintainer during Junio's absence, that is) agreed, and that is when the glamor of the --preserve-merges design started to fall apart rather quickly and unglamorously. The reason? In --preserve-merges mode, the parents of a merge commit (or for that matter, of *any* commit) were not stated explicitly, but were *implied* by the commit name passed to the `pick` command. This made it impossible, for example, to reorder commits. Not to mention to flatten the branch topology or, deity forbid, to split topic branches into two. Alas, these shortcomings also prevented that mode (whose original purpose was to serve Git for Windows' needs, with the additional hope that it may be useful to others, too) from serving Git for Windows' needs. Five years later, when it became really untenable to have one unwieldy, big hodge-podge patch series of partly related, partly unrelated patches in Git for Windows that was rebased onto core Git's tags from time to time (earning the undeserved wrath of the developer of the ill-fated git-remote-hg series that first obsoleted Git for Windows' competing approach, only to be abandoned without maintainer later) was really untenable, the "Git garden shears" were born [*1*/*2*]: a script, piggy-backing on top of the interactive rebase, that would first determine the branch topology of the patches to be rebased, create a pseudo todo list for further editing, transform the result into a real todo list (making heavy use of the `exec` command to "implement" the missing todo list commands) and finally recreate the patch series on top of the new base commit. That was in 2013. And it took about three weeks to come up with the design and implement it as an out-of-tree script. Needless to say, the implementation needed quite a few years to stabilize, all the while the design itself proved itself sound. With this patch, the goodness of the Git garden shears comes to `git rebase -i` itself. Passing the `--recreate-merges` option will generate a todo list that can be understood readily, and where it is obvious how to reorder commits. New branches can be introduced by inserting `label` commands and calling `merge