Once upon a time, I dreamt of an interactive rebase that would not
flatten branch structure, but instead recreate the commit topology
My original attempt was --preserve-merges, but that design was so
limited that I did not even enable it in interactive mode.
Subsequently, it *was* enabled in interactive mode, with the predictable
consequences: as the --preserve-merges design does not allow for
specifying the parents of merge commits explicitly, all the new commits'
parents are defined *implicitly* by the previous commit history, and
hence it is *not possible to even reorder commits*.
This design flaw cannot be fixed. Not without a complete re-design, at
least. This patch series offers such a re-design.
Think of --recreate-merges as "--preserve-merges done right". It
introduces new verbs for the todo list, `label`, `reset` and `merge`.
For a commit topology like this:
A - B - C
the generated todo list would look like this:
# branch D
pick 0123 A
pick 1234 D
pick 2345 B
merge 3456 D C
There are more patches in the pipeline, based on this patch series, but
left for later in the interest of reviewable patch series: one mini
series to use the sequencer even for `git rebase -i --root`, and another
one to add support for octopus merges to --recreate-merges.
Johannes Schindelin (8):
sequencer: introduce new commands to reset the revision
sequencer: introduce the `merge` command
sequencer: fast-forward merge commits, if possible
rebase-helper --make-script: introduce a flag to recreate merges
rebase: introduce the --recreate-merges option
sequencer: handle autosquash and post-rewrite for merge commands
pull: accept --rebase=recreate to recreate the branch topology
rebase -i: introduce --recreate-merges=no-rebase-cousins
Documentation/config.txt | 8 +
Documentation/git-pull.txt | 5 +-
Documentation/git-rebase.txt | 13 +-
builtin/pull.c | 14 +-
builtin/rebase--helper.c | 13 +-
builtin/remote.c | 2 +
contrib/completion/git-completion.bash | 4 +-
git-rebase--interactive.sh | 6 +
git-rebase.sh | 16 +
refs.c | 3 +-
sequencer.c | 697 ++++++++++++++++++++++++++++++++-
sequencer.h | 9 +
t/t3430-rebase-recreate-merges.sh | 208 ++++++++++
13 files changed, 977 insertions(+), 21 deletions(-)
create mode 100755 t/t3430-rebase-recreate-merges.sh