Re: git rebase: retain original head?

[Nazri Ramliy <ayiehere@gmail.com>]

On Wed, Jan 9, 2019 at 10:08 PM Johannes Schindelin
<Johannes.Schindelin@gmx.de> wrote:
> Having said that, it is an unintended regression in the built-in rebase.
> Markus, could you come up with a minimal test case, preferably in the form
> of a patch to t/t3415-rebase-autosquash.sh?

Something like this, perhaps? ("gmail converts tabs to spaces" caveat
applies to the diff formatting):

--8<--
diff --git t/t3400-rebase.sh t/t3400-rebase.sh
index 3e73f7584c..cb55597a8b 100755
--- t/t3400-rebase.sh
+++ t/t3400-rebase.sh
@@ -59,6 +59,13 @@ test_expect_success 'rebase against master' '
  git rebase master
 '

+test_expect_success 'rebase sets ORIG_HEAD' '
+ echo Add B. > expect &&
+ echo Modify A. >> expect &&
+ git log --oneline --format=%s ORIG_HEAD.. > actual &&
+ test_cmp expect actual
+'
+
 test_expect_success 'rebase, with <onto> and <upstream> specified as
:/quuxery' '
  test_when_finished "git branch -D torebase" &&
  git checkout -b torebase my-topic-branch^ &&
-->8--

Bisect shows that the first bad commit is this one:

commit 21853626eac565dd42572d90724b29863f61eb3b
Author: Johannes Schindelin <johannes.schindelin@gmx.de>
Date:   Fri Jan 18 07:09:27 2019 -0800

    built-in rebase: call `git am` directly

I verified that by undoing the crux of that commit, and that fixes the
failing test:

-->8--
diff --git builtin/rebase.c builtin/rebase.c
index 7c7bc13e91..848f6740a0 100644
--- builtin/rebase.c
+++ builtin/rebase.c
@@ -728,11 +728,6 @@ static int run_specific_rebase(struct rebase_options *opts)
  goto finished_rebase;
  }

- if (opts->type == REBASE_AM) {
- status = run_am(opts);
- goto finished_rebase;
- }
-
  add_var(&script_snippet, "GIT_DIR", absolute_path(get_git_dir()));
  add_var(&script_snippet, "state_dir", opts->state_dir);

--8<--

But something seems off by my bisection in that the "bad" commit
happens about 10 days after this email thread :/

nazri