From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-3.9 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI,SPF_HELO_NONE,SPF_NONE shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id 467461F461 for ; Tue, 9 Jul 2019 20:51:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728679AbfGIUvw (ORCPT ); Tue, 9 Jul 2019 16:51:52 -0400 Received: from mail-io1-f41.google.com ([209.85.166.41]:36869 "EHLO mail-io1-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726401AbfGIUvw (ORCPT ); Tue, 9 Jul 2019 16:51:52 -0400 Received: by mail-io1-f41.google.com with SMTP id q22so24338356iog.4 for ; Tue, 09 Jul 2019 13:51:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=atlassian-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=xRDo5kykJWyqQPNlAx1HNkoFIeizvwaghtbk+Wqx+Vo=; b=q1VxN7Ka1l73hTp6dLc/UMoT3BHBdrZqFipAlvB2uiveN6p3j5pWX3Nh82tsPRTrtL XauJtCN0AJuJRd4/DIDjRqKYZvyAZMv4eioZlxNQm7vNiuJxqtW4TurF1jqhj7CrWQjf zbF8YeINXQR5siMFPtdSNDKfCM/9x/KCyrTCG/MqUjCUkdKkNDd1Ux7SPSeOIkaC/p8d YCaO64qlHkIepakhCai76mGlQMTBggVHG9ey4oYgMKnxHnOcRUAxgrVsQ2D0lEFoDcFj 2xYBRKrwxGpZkSm9qbN1eJx/cgouGCxMH0hfSbzdNygqVJtlI0HqLugjszcLi/3iiouU m5UA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=xRDo5kykJWyqQPNlAx1HNkoFIeizvwaghtbk+Wqx+Vo=; b=TC5VpAlRjWKpoeepj5KqMews/XwEAURqaiS8EDhJGdv8DovSCQqNP+2a64P3FBC2yc Nf/ugEnkyWM4w2r08jwG6+mBxDdA2o21m3ui7lvjSofZbOMYlbRH89J2eNSkAUW5EOwD 2Rn5qIEivMGIEwn68WYvbY931UcIwaLAAikaM9d6tCWuHa4tsWhUIqahGwlIeQY1K4zp yuy3DQvObDvRXclUyK65nTZmwJhbbygrf2Jj3YG6CKGAwJY2WWvJsYL9GNjZJVKO8f10 qUuo37u149E9tc+AQXwXmSyztVh74p3AClku/7g2F3QZjAXV2sQxJsq4rPVZfwXD4Cl8 G9Ug== X-Gm-Message-State: APjAAAXczHSGFizCUL4MCkUc2LXlc2IiNY2gQgZb+da+tHmGxA0ZZCp3 NhiX+9/6olhaO8uJiWBbM6QZ1m62mtjF/SkDrskQFg== X-Google-Smtp-Source: APXvYqzhElS3yti0dZAKj3INJCZ9QpgG2/k8spgx2/SQFCw6d2rczfRfDk5ESB1yid1zHwdxj6smE2SZmrhjpi8VH1U= X-Received: by 2002:a02:cc8f:: with SMTP id s15mr29760852jap.94.1562705510798; Tue, 09 Jul 2019 13:51:50 -0700 (PDT) MIME-Version: 1.0 References: <423596682.8516.1562665372094@office.mailbox.org> <1152121968.7459.1562688927235@office.mailbox.org> <275487563.12198.1562691633735@office.mailbox.org> In-Reply-To: From: Bryan Turner Date: Tue, 9 Jul 2019 13:51:39 -0700 Message-ID: Subject: Re: Unexpected or wrong ff, no-ff and ff-only behaviour To: Elijah Newren Cc: usbuser@mailbox.org, Junio C Hamano , Git Mailing List Content-Type: text/plain; charset="UTF-8" Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Tue, Jul 9, 2019 at 1:33 PM Elijah Newren wrote: > > On Tue, Jul 9, 2019 at 10:00 AM wrote: > > > > Additionally I would also want to change the wording for --ff-only, as it currently reads as if it only performs a check (which would lead to the expected behaviour) but does more than that, as it prevents "real merges" altogether. > > You've lost me again, I think. You expect --ff-only to only perform a > check, i.e. to not update anything and thus only report on whether a > fast-forward would be possible, but leave the branch exactly where it > started no matter what? > > Or is it just still not clear that a fast forward by definition is not > "a real merge", i.e. it means to update using a mechanism that doesn't > involve creating any new commits? I think this is something I've seen come up on the list before[1] (Roland can correct me if I'm wrong). What I've seen asked for before is the ability to pass the combination "--ff-only --no-ff" and have that: * Ensure the branch to be merged is fast-forward from the current branch (i.e., to ensure no merge commit is actually necessary), but * Create a redundant merge commit anyway This retains the ancestry (as in, it shows where the branches were merged), but the merge is always effectively a no-op (no risk of unintended interactions, the sort of subtle breakages where the merge succeeds but the code on each "side" isn't entirely compatible, resulting in broken compilation and/or tests and/or runtime). Best regards, Bryan Turner [1] https://public-inbox.org/git/CAP4gbxqjHzqHhPuNK8UOwPMa46g2=vcNSk1AvGjxN8s+ou-0Dw@mail.gmail.com/