[PATCH v7 0/6] rebase: learn --keep-base

[Denton Liu <liu.denton@gmail.com>]

Hi all,

Sorry for yet another reroll. I realised earlier that rebase doesn't use
--git-completion-helper for completion so I had to manually insert
--keep-base into the completion script.

Between this and forgetting to update the comment around the
can_fast_forward call, I figured with the number of mistakes to fix, it
was worth another reroll.

Thanks,

Denton

---

This patchset now depends "[PATCH 1/8] tests (rebase): spell out the
`--keep-empty` option" which is the first patch of Johannes's "Do not
use abbreviated options in tests" patchset[1]. (Thanks for catching
that, Johannes!)

Changes since v1:

* Squashed old set into one patch
* Fixed indentation style and dangling else
* Added more documentation after discussion with Ævar

Changes since v2:

* Add testing for rebase --fork-point behaviour
* Add testing for rebase fast-forward behaviour
* Make rebase --onto fast-forward in more cases
* Update documentation to include use-case

Changes since v3:

* Fix tests failing on bash 4.2
* Fix typo in t3431 comment

Changes since v4:

* Make rebase --fork-point fast-forward in more cases

Changes since v5:

* Fix graph illustrations so that the "branch off" is visually in the
  correct place
* Refactor if-else in can_fast_forward into one-level-deep ifs to
  increase clarity

Changes since v6:

* Remove redundant braces around if
* Update comment around can_fast_forward call
* Add completion for rebase

[1]: https://public-inbox.org/git/a1b4b74b9167e279dae4cd8c58fb28d8a714a66a.1553537656.git.gitgitgadget@gmail.com/


Denton Liu (6):
  t3431: add rebase --fork-point tests
  t3432: test rebase fast-forward behavior
  rebase: refactor can_fast_forward into goto tower
  rebase: fast-forward --onto in more cases
  rebase: fast-forward --fork-point in more cases
  rebase: teach rebase --keep-base

 Documentation/git-rebase.txt           | 30 ++++++++-
 builtin/rebase.c                       | 87 +++++++++++++++++++-------
 contrib/completion/git-completion.bash |  2 +-
 t/t3400-rebase.sh                      |  2 +-
 t/t3404-rebase-interactive.sh          |  2 +-
 t/t3416-rebase-onto-threedots.sh       | 57 +++++++++++++++++
 t/t3431-rebase-fork-point.sh           | 57 +++++++++++++++++
 t/t3432-rebase-fast-forward.sh         | 83 ++++++++++++++++++++++++
 8 files changed, 291 insertions(+), 29 deletions(-)
 create mode 100755 t/t3431-rebase-fork-point.sh
 create mode 100755 t/t3432-rebase-fast-forward.sh

Interdiff against v6:
diff --git a/builtin/rebase.c b/builtin/rebase.c
index cf63195e7d..19e7e2a1c9 100644
--- a/builtin/rebase.c
+++ b/builtin/rebase.c
@@ -1723,7 +1723,9 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
 
 	/*
 	 * Check if we are already based on onto with linear history,
-	 * but this should be done if this is not an interactive rebase.
+	 * in which case we could fast-forward without replacing the commits
+	 * with new commits recreated by replaying their changes. This
+	 * optimization must not be done if this is an interactive rebase.
 	 */
 	if (can_fast_forward(options.onto, options.upstream, options.restrict_revision,
 		    &options.orig_head, &merge_base) &&
diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
index 976e4a6548..f9dc431a39 100644
--- a/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash
@@ -2027,7 +2027,7 @@ _git_rebase ()
 			--autosquash --no-autosquash
 			--fork-point --no-fork-point
 			--autostash --no-autostash
-			--verify --no-verify
+			--verify --no-verify --keep-base
 			--keep-empty --root --force-rebase --no-ff
 			--rerere-autoupdate
 			--exec
-- 
2.21.0.967.gf85e14fd49