public inbox for git@vger.kernel.org 
 help / color / mirror / Atom feed
From: Siddharth Asthana <siddharthasthana31@gmail•com>
To: Elijah Newren <newren@gmail•com>
Cc: Junio C Hamano <gitster@pobox•com>,
	Johannes Schindelin <Johannes.Schindelin@gmx•de>,
	git@vger•kernel.org, christian.couder@gmail•com, ps@pks•im,
	phillip.wood123@gmail•com, phillip.wood@dunelm•org.uk,
	karthik.188@gmail•com, code@khaugsbakk•name, rybak.a.v@gmail•com,
	jltobler@gmail•com, toon@iotcl•com, johncai86@gmail•com
Subject: Re: [PATCH 0/1] replay: add --revert option to reverse commit changes
Date: Fri, 28 Nov 2025 13:54:07 +0530	[thread overview]
Message-ID: <c930d6df-5dc4-401f-a9a1-eb2f00b2e837@gmail.com> (raw)
In-Reply-To: <CABPp-BFsDJVtR6RV8KugCW2vmbD1=rTOKLp2jeawRfuPUEsNEA@mail.gmail.com>


On 28/11/25 13:37, Elijah Newren wrote:
> On Thu, Nov 27, 2025 at 11:21 AM Siddharth Asthana
> <siddharthasthana31@gmail•com> wrote:
>> On 27/11/25 02:34, Junio C Hamano wrote:
>>> Siddharth Asthana <siddharthasthana31@gmail•com> writes:
>>>
>>>> 1. For quick undoing an entire MR, the `merge-tree` approach you
>>>> suggest is indeed more efficient and avoids unnecessary intermediate
>>>> conflicts.
>>>>
>>>> 2. For commit-by-commit reverts, we need individual revert commits with
>>>> proper attribution (which commit is being reverted) for auditability and
>>>> history clarity. This is particularly useful when only specific commits
>>>> from a merged branch need to be reverted.
>>> These are both good workflows with appropriate uses.  To make the
>>> tool useful for #2, it needs to be able to allow "I have merged a
>>> topic with 7 commits, but the first commit and the fourth commit are
>>> faulty and I need to revert them", i.e., not just a range
>>
>> Since replay uses the same rev-list machinery as `git log`, users can
>> already specify disconnected commits:
>>
>>       git replay --revert <target> <commit1> <commit4>


Hi Elijah,


> No, this command does not specify disconnected commits.  A <range> of
> "<commit1> <commit4>" specifies all commits in the history of either
> <commit1> or <commit4>.


You are right, I misspoke. I was conflating the command-line syntax with 
what the revision machinery actually produces after prepare_revision_walk().


>    Thus, this example command line would be
> asking to revert all commits in the history of either <commit1> or
> <commit4> (all the way back to the initial commit), rather than just
> reverting those two commits.  This is just like how
>     git log <commit1> <commit4>
> shows all commits in the history of either <commit1> or <commit4>
> instead of just showing those two commits.
>
> There isn't really a mechanism in replay right now to handle a
> disconnected set of commits for either --advance or --revert.


Right, the check at line 190 in replay.c:

     if (rinfo.positive_refexprs > 1)
         die(_("cannot advance target with multiple sources..."));

fires before we even get to the revision walk.


> If there were, it'd probably look like
>
>     git replay --advance <branch> --no-walk <commit1> <commit4>
>
> but the code isn't set up to check whether you specified --no-walk,
> and thinks "Um, you specified multiple branches here and it's not
> clear the order in which to cherry-pick them" so it throws an error:
>
> $ git replay --advance main --no-walk Commit1 Commit7
> fatal: cannot advance target with multiple sources because ordering
> would be ill-defined
>
> If you comment out the relevant check which dies with that error, then
> you end up in some codepath that segfaults instead (not-properly
> initialized commit/tree objects or something?).  I'm sure that could
> be fixed, but "users can already specify disconnected commits" is just
> not accurate.
>
>> I will add a test to verify this works and document the capability.
> Supporting --no-walk so that folks can do disconnected commits for
> both --advance and --revert may be nice, but given that it's missing
> for --advance already, it might be considered a separate change from
> your current submission.  I'll leave that up to you.



Agreed. I will keep the current submission focused on basic --revert 
functionality. Supporting --no-walk for disconnected commits (benefiting 
both --advance and --revert) would make a nice follow-up series.

Thanks for the correction.

Siddharth


  reply	other threads:[~2025-11-28  8:24 UTC|newest]

Thread overview: 96+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-11-25 17:00 [PATCH 0/1] replay: add --revert option to reverse commit changes Siddharth Asthana
2025-11-25 17:00 ` [PATCH 1/1] " Siddharth Asthana
2025-11-25 19:22   ` Junio C Hamano
2025-11-25 19:30     ` Junio C Hamano
2025-11-25 19:39       ` Junio C Hamano
2025-11-25 20:06         ` Junio C Hamano
2025-11-26 19:31           ` Siddharth Asthana
2025-11-26 19:28         ` Siddharth Asthana
2025-11-26 19:26     ` Siddharth Asthana
2025-11-26 21:13       ` Junio C Hamano
2025-11-27 19:23         ` Siddharth Asthana
2025-11-26 11:10   ` Phillip Wood
2025-11-26 17:35     ` Elijah Newren
2025-11-26 18:41       ` Junio C Hamano
2025-11-26 21:17         ` Junio C Hamano
2025-11-26 23:06           ` Elijah Newren
2025-11-26 23:14             ` Junio C Hamano
2025-11-26 23:57               ` Elijah Newren
2025-11-26 19:50       ` Siddharth Asthana
2025-11-26 19:39     ` Siddharth Asthana
2025-11-27 16:21       ` Phillip Wood
2025-11-27 19:24         ` Siddharth Asthana
2025-11-25 17:25 ` [PATCH 0/1] " Johannes Schindelin
2025-11-25 18:02   ` Junio C Hamano
2025-11-26 19:18   ` Siddharth Asthana
2025-11-26 21:04     ` Junio C Hamano
2025-11-27 19:21       ` Siddharth Asthana
2025-11-27 20:17         ` Junio C Hamano
2025-11-28  8:07         ` Elijah Newren
2025-11-28  8:24           ` Siddharth Asthana [this message]
2025-11-28 16:35             ` Junio C Hamano
2025-11-28 17:07               ` Elijah Newren
2025-11-28 20:50                 ` Junio C Hamano
2025-11-28 22:03                   ` Elijah Newren
2025-11-29  5:59                     ` Junio C Hamano
2025-12-02 20:16 ` [PATCH v2 0/2] replay: add --revert mode " Siddharth Asthana
2025-12-02 20:16   ` [PATCH v2 1/2] sequencer: extract revert message formatting into shared function Siddharth Asthana
2025-12-05 11:33     ` Patrick Steinhardt
2025-12-07 23:00       ` Siddharth Asthana
2025-12-08  7:07         ` Patrick Steinhardt
2026-02-11 13:03           ` Toon Claes
2026-02-11 13:40             ` Patrick Steinhardt
2026-02-11 15:23             ` Kristoffer Haugsbakk
2026-02-11 17:41               ` Junio C Hamano
2026-02-18 22:53             ` Siddharth Asthana
2025-12-02 20:16   ` [PATCH v2 2/2] replay: add --revert mode to reverse commit changes Siddharth Asthana
2025-12-05 11:33     ` Patrick Steinhardt
2025-12-07 23:03       ` Siddharth Asthana
2025-12-16 16:23     ` Phillip Wood
2026-02-18 23:42   ` [PATCH v3 0/2] " Siddharth Asthana
2026-02-18 23:42     ` [PATCH v3 1/2] sequencer: extract revert message formatting into shared function Siddharth Asthana
2026-02-20 17:01       ` Toon Claes
2026-02-25 21:53         ` Junio C Hamano
2026-03-06  4:55           ` Siddharth Asthana
2026-03-06  4:31         ` Siddharth Asthana
2026-02-26 14:27       ` Phillip Wood
2026-03-06  5:00         ` Siddharth Asthana
2026-02-18 23:42     ` [PATCH v3 2/2] replay: add --revert mode to reverse commit changes Siddharth Asthana
2026-02-20 17:35       ` Toon Claes
2026-02-20 20:23         ` Junio C Hamano
2026-02-23  9:13         ` Christian Couder
2026-02-23 11:23           ` Toon Claes
2026-03-06  5:05         ` Siddharth Asthana
2026-02-26 14:45       ` Phillip Wood
2026-03-06  5:28         ` Siddharth Asthana
2026-03-06 15:52           ` Phillip Wood
2026-03-06 16:20             ` Siddharth Asthana
2026-03-13  5:40     ` [PATCH v4 0/2] " Siddharth Asthana
2026-03-13  5:40       ` [PATCH v4 1/2] sequencer: extract revert message formatting into shared function Siddharth Asthana
2026-03-13 15:53         ` Junio C Hamano
2026-03-16 19:12           ` Toon Claes
2026-03-16 16:57         ` Phillip Wood
2026-03-13  5:40       ` [PATCH v4 2/2] replay: add --revert mode to reverse commit changes Siddharth Asthana
2026-03-16 16:57         ` Phillip Wood
2026-03-16 19:52         ` Toon Claes
2026-03-17 10:11           ` Phillip Wood
2026-03-16 16:59       ` [PATCH v4 0/2] " Phillip Wood
2026-03-16 19:53       ` Toon Claes
2026-03-24 22:03       ` [PATCH v5 " Siddharth Asthana
2026-03-24 22:04         ` [PATCH v5 1/2] sequencer: extract revert message formatting into shared function Siddharth Asthana
2026-03-24 22:04         ` [PATCH v5 2/2] replay: add --revert mode to reverse commit changes Siddharth Asthana
2026-03-25  6:29           ` Junio C Hamano
2026-03-25 15:10             ` Toon Claes
2026-03-25 15:38               ` Siddharth Asthana
2026-03-25 16:44               ` Phillip Wood
2026-03-25 15:36             ` Siddharth Asthana
2026-03-25 20:23         ` [PATCH v6 0/2] " Siddharth Asthana
2026-03-25 20:23           ` [PATCH v6 1/2] sequencer: extract revert message formatting into shared function Siddharth Asthana
2026-03-25 20:23           ` [PATCH v6 2/2] replay: add --revert mode to reverse commit changes Siddharth Asthana
2026-03-28  4:33             ` Tian Yuchen
2026-03-29 16:17               ` Siddharth Asthana
2026-03-30 17:23                 ` Tian Yuchen
2026-03-31  8:08                   ` Toon Claes
2026-03-31  8:11                 ` Toon Claes
2026-03-25 20:23           ` [PATCH v6 1/2] sequencer: extract revert message formatting into shared function Siddharth Asthana
2026-03-25 20:23           ` [PATCH v6 2/2] replay: add --revert mode to reverse commit changes Siddharth Asthana

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=c930d6df-5dc4-401f-a9a1-eb2f00b2e837@gmail.com \
    --to=siddharthasthana31@gmail$(echo .)com \
    --cc=Johannes.Schindelin@gmx$(echo .)de \
    --cc=christian.couder@gmail$(echo .)com \
    --cc=code@khaugsbakk$(echo .)name \
    --cc=git@vger$(echo .)kernel.org \
    --cc=gitster@pobox$(echo .)com \
    --cc=jltobler@gmail$(echo .)com \
    --cc=johncai86@gmail$(echo .)com \
    --cc=karthik.188@gmail$(echo .)com \
    --cc=newren@gmail$(echo .)com \
    --cc=phillip.wood123@gmail$(echo .)com \
    --cc=phillip.wood@dunelm$(echo .)org.uk \
    --cc=ps@pks$(echo .)im \
    --cc=rybak.a.v@gmail$(echo .)com \
    --cc=toon@iotcl$(echo .)com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox