A while a go Philippe reported [1] that he was surprised 'git rebase
--keep-base' removed commits that had been cherry-picked upstream even
though to branch was not being rebased. I think it is also surprising if
'--keep-base' changes the base of the branch without '--fork-point' being
explicitly given on the command line. This series therefore changes the
default behavior of '--keep-base' to imply '--reapply-cherry-picks' and
'--no-fork-point' so that the base of the branch is unchanged and no commits
are removed.

The first 3 patches are preparatory cleanups and refactorings, the last 2
patches then implement the new defaults for --keep-base.

[1]
https://lore.kernel.org/git/0EA8C067-5805-40A7-857A-55C2633B8570@gmail.com/

Phillip Wood (5):
  t3416: set $EDITOR in subshell
  rebase: store orig_head as a commit
  rebase: factor out merge_base calculation
  rebase --keep-base: imply --reapply-cherry-picks
  rebase --keep-base: imply --no-fork-point

 Documentation/git-rebase.txt     |   2 +-
 builtin/rebase.c                 | 116 +++++++++++++++++++------------
 t/t3416-rebase-onto-threedots.sh |  52 +++++++++++---
 t/t3431-rebase-fork-point.sh     |   2 +-
 4 files changed, 114 insertions(+), 58 deletions(-)

base-commit: afa70145a25e81faa685dc0b465e52b45d2444bd

Submitted-As: https://lore.kernel.org/git/pull.1323.git.1660576283.gitgitgadget@gmail.com