Re: [PATCH v3 00/10] rebase: dereference tags

>
> Thanks for the comments on V2. Here are the changes from that version:
>
>  * dropped the controversial cleanup that was patch 8
>  * reworded patch 10 as suggested by Junio
>
> Cover letter for v2: Thanks to Ævar and Johannes for their comments.

>
>  * Changed "! test_cmp_rev" to "test_cmp_rev !" (suggested by Ævar)
>  * Fixed the quoting for the title of the "rebase --quit" tests.
>  * Reworked the last commit to handle the error case first (suggested by
>    Ævar)
>  * Tweaked the commit messages for patches 8 & 11
>  * Rebased onto 31e4a0db03 ("Merge branch 'ab/rebase-fatal-fatal-fix'",
>    2021-09-08) to avoid a merge conflict that upset gitgitgadget
>
> Cover letter for V1: Aborting a rebase stated with git rebase <upstream>
> <tag-object> should checkout the commit pointed to by . Instead it gives
>
>     error: update_ref failed for ref 'HEAD': cannot update ref 'HEAD': trying to write non-commit object       710d743b2b9892457fdcc3970f397e6ec07447e0 to branch 'HEAD'
>
>
> The fix for that is in the last patch, the rest of the patches are cleanups
> to t3407 and builtin/rebase.c
>
> Phillip Wood (10):
>   t3407: run tests in $TEST_DIRECTORY
>   t3407: use test_commit
>   t3407: use test_cmp_rev
>   t3407: rename a variable
>   t3407: use test_path_is_missing
>   t3407: strengthen rebase --abort tests
>   t3407: rework rebase --quit tests
>   rebase: use our standard error return value
>   rebase: use lookup_commit_reference_by_name()
>   rebase: dereference tags
>
>  builtin/rebase.c        |  49 ++++++++-----------
>  t/t3407-rebase-abort.sh | 105 ++++++++++++++++++----------------------
>  2 files changed, 67 insertions(+), 87 deletions(-)
>
>
> base-commit: 31e4a0db0337e2aa972d9b9f11a332dff7c4cbcb
> Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1033%2Fphillipwood%2Fwip%2Frebase-handle-tags-v3
> Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1033/phillipwood/wip/rebase-handle-tags-v3
> Pull-Request: https://github.com/gitgitgadget/git/pull/1033
>
> Range-diff vs v2:
>
>   1:  bac009d8543 =  1:  bac009d8543 t3407: run tests in $TEST_DIRECTORY
>   2:  abfffb31a56 =  2:  abfffb31a56 t3407: use test_commit
>   3:  7755ce17fef =  3:  7755ce17fef t3407: use test_cmp_rev
>   4:  38eee11baf5 =  4:  38eee11baf5 t3407: rename a variable
>   5:  61a37c89f1e =  5:  61a37c89f1e t3407: use test_path_is_missing
>   6:  6866630528b =  6:  6866630528b t3407: strengthen rebase --abort tests
>   7:  fd55a3196b1 =  7:  fd55a3196b1 t3407: rework rebase --quit tests
>   8:  ad3c4efc027 <  -:  ----------- rebase: remove redundant strbuf
>   9:  ad940b633d0 !  8:  d3af62c746c rebase: use our standard error return value
>      @@ builtin/rebase.c: int cmd_rebase(int argc, const char **argv, const char *prefix
>                 } else if (!(options.flags & REBASE_NO_QUIET))
>                         ; /* be quiet */
>       @@ builtin/rebase.c: int cmd_rebase(int argc, const char **argv, const char *prefix)
>      -          reset_head(the_repository, NULL, "Fast-forwarded", options.head_name,
>      -                     RESET_HEAD_REFS_ONLY, "HEAD", buf.buf,
>      +                     RESET_HEAD_REFS_ONLY, "HEAD", msg.buf,
>                            DEFAULT_REFLOG_ACTION);
>      +          strbuf_release(&msg);
>       -         ret = !!finish_rebase(&options);
>       +         ret = finish_rebase(&options);
>                 goto cleanup;
>  10:  bc103e703e8 =  9:  4eedd3ae766 rebase: use lookup_commit_reference_by_name()
>  11:  951de6bb199 ! 10:  55a6250ab38 rebase: dereference tags
>      @@ Metadata
>        ## Commit message ##
>           rebase: dereference tags
>
>      -    Aborting a rebase stated with 'git rebase <upstream> <tag-object>'
>      -    should checkout the commit pointed to by <tag-object>. Instead it gives
>      +    A rebase started with 'git rebase <A> <B>' is conceptually to first
>      +    checkout <B> and run 'git rebase <A>' starting from that state.  'git
>      +    rebase --abort' in the middle of such a rebase should take us back to
>      +    the state we checked out <B>.
>
>      -        error: update_ref failed for ref 'HEAD': cannot update ref 'HEAD':
>      -        trying to write non-commit object
>      -        710d743b2b9892457fdcc3970f397e6ec07447e0 to branch 'HEAD'
>      +    This used to work, even when <B> is a tag that points at a commit,
>      +    until Git 2.20.0 when the command was reimplemented in C.  The command
>      +    now complains that the tag object itself cannot be checked out, which
>      +    may be technically correct but is not what the user asked to do.
>
>      -    This is because when we parse the command line arguments although we
>      -    check that the tag points to a commit we remember the oid of the tag
>      -    and try and checkout that object rather than the commit it points
>      -    to. Fix this by using lookup_commit_reference_by_name() when parsing
>      -    the command line.
>      +    Fix this old regression by using lookup_commit_reference_by_name()
>      +    when parsing <B>. The scripted version did not need to peel the tag
>      +    because the commands it passed the tag to (e.g 'git reset') peeled the
>      +    tag themselves.
>
>           Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
>           ---
>
> --
> gitgitgadget