From: Taylor Blau <me@ttaylorr.com>
To: Jeff King <peff@peff.net>
Cc: Martin von Zweigbergk <martinvonz@google.com>,
Junio C Hamano <gitster@pobox.com>,
Git Mailing List <git@vger.kernel.org>
Subject: Re: Bug in `git branch --delete main` when on other orphan branch
Date: Tue, 1 Nov 2022 16:12:06 -0400 [thread overview]
Message-ID: <Y2F9lkCWf/2rjT2E@nand.local> (raw)
In-Reply-To: <Y2DxxZAFbN8juHY6@coredump.intra.peff.net>
On Tue, Nov 01, 2022 at 06:15:33AM -0400, Jeff King wrote:
> On Fri, Oct 28, 2022 at 10:46:37PM -0700, Martin von Zweigbergk wrote:
>
> > I did this:
> > git init test
> > cd test
> > echo a > file
> > git add file
> > git commit -m a
> > git checkout --orphan other
> > git branch --delete main
> >
> > The last command fails with:
> > fatal: Couldn't look up commit object for HEAD
> >
> > That's a bug, right? I can of course work around it with `rm
> > .git/refs/heads/main`.
>
> Sort of. This is part of the "is the thing we are deleting merged into
> HEAD" check. It tries to look up the HEAD and calls die() when it can't.
> The more correct thing, I think, would be for it to just return "nope,
> there is no HEAD so nothing is merged into it".
Yeah, I think that it's fair to call being unable to find HEAD in 'git
branch -d' when we are detached a bug. Indeed, if we can't find a HEAD,
then that's fine (there is just nothing merged into it, as you note).
> And in that case I think the HEAD check calling die() is actively doing
> the wrong thing, and would prevent an otherwise successful deletion.
>
> The fix might be as simple as:
>
> diff --git a/builtin/branch.c b/builtin/branch.c
> index 15be0c03ef..f6ff9084c8 100644
> --- a/builtin/branch.c
> +++ b/builtin/branch.c
> @@ -235,11 +235,8 @@ static int delete_branches(int argc, const char **argv, int force, int kinds,
> }
> branch_name_pos = strcspn(fmt, "%");
>
> - if (!force) {
> + if (!force)
> head_rev = lookup_commit_reference(the_repository, &head_oid);
> - if (!head_rev)
> - die(_("Couldn't look up commit object for HEAD"));
> - }
>
> for (i = 0; i < argc; i++, strbuf_reset(&bname)) {
> char *target = NULL;
>
> as the later code seems to do the right thing with the NULL head_rev. It
> would definitely need more careful investigation (and tests!) to confirm
> that, though.
Yeah, that looks reasonable to me. Presumably we want a small test, as
well, but I doubt that is any more complicated than:
--- 8< ---
diff --git a/t/t3200-branch.sh b/t/t3200-branch.sh
index 7f605f865b..6ace22f7ce 100755
--- a/t/t3200-branch.sh
+++ b/t/t3200-branch.sh
@@ -279,6 +279,14 @@ test_expect_success 'git branch -M and -C fail on detached HEAD' '
test_cmp expect err
'
+test_expect_success 'git branch -d on detached HEAD' '
+ test_when_finished "git checkout main && git branch -D other" &&
+ git branch other &&
+ git checkout --orphan orphan &&
+ test_must_fail git branch -d other 2>err &&
+ grep "not fully merged" err
+'
+
test_expect_success 'git branch -v -d t should work' '
git branch t &&
git rev-parse --verify refs/heads/t &&
--- >8 ---
I'm happy to wrap all of that up into a patch, and equally happy for you
to do so (feel free to forge my S-o-b here if you do).
Thanks,
Taylor
next prev parent reply other threads:[~2022-11-01 20:12 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-29 5:46 Bug in `git branch --delete main` when on other orphan branch Martin von Zweigbergk
2022-11-01 10:15 ` Jeff King
2022-11-01 15:31 ` Martin von Zweigbergk
2022-11-01 20:12 ` Taylor Blau [this message]
2022-11-01 20:14 ` Bug in `git branch --delete main` when on other orphan brancht Taylor Blau
2022-11-01 21:45 ` Jeff King
2022-11-02 0:59 ` Taylor Blau
2022-11-01 20:32 ` [PATCH] branch: gracefully handle '-d' on detached HEAD Taylor Blau
2022-11-02 5:27 ` [PATCH v2] branch: gracefully handle '-d' on orphan HEAD Jeff King
2022-11-04 1:26 ` Rubén Justo
2022-11-04 5:36 ` Jeff King
2022-11-06 22:22 ` Rubén Justo
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
List information: http://vger.kernel.org/majordomo-info.html
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=Y2F9lkCWf/2rjT2E@nand.local \
--to=me@ttaylorr.com \
--cc=git@vger.kernel.org \
--cc=gitster@pobox.com \
--cc=martinvonz@google.com \
--cc=peff@peff.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public inbox
https://80x24.org/mirrors/git.git
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).