-f::
--force-rebase::
Force the rebase even if the current branch is a descendant
- of the commit you are rebasing onto. Normally the command will
+ of the commit you are rebasing onto. Normally non-interactive rebase will
exit with the message "Current branch is up to date" in such a
situation.
+ Incompatible with the --interactive option.
++
+You may find this (or --no-ff with an interactive rebase) helpful after
+reverting a topic branch merge, as this option recreates the topic branch with
+fresh commits so it can be remerged successfully without needing to "revert
+the reversion" (see the
+link:howto/revert-a-faulty-merge.txt[revert-a-faulty-merge How-To] for details).
--ignore-whitespace::
--whitespace=<option>::
commit to be modified, and change the action of the moved
commit from `pick` to `squash` (or `fixup`).
+
-This option is only valid when '--interactive' option is used.
+This option is only valid when the '--interactive' option is used.
+
+--no-ff::
+ With --interactive, cherry-pick all rebased commits instead of
+ fast-forwarding over the unchanged ones. This ensures that the
+ entire history of the rebased branch is composed of new commits.
++
+Without --interactive, this is a synonym for --force-rebase.
++
+You may find this helpful after reverting a topic branch merge, as this option
+recreates the topic branch with fresh commits so it can be remerged
+successfully without needing to "revert the reversion" (see the
+link:howto/revert-a-faulty-merge.txt[revert-a-faulty-merge How-To] for details).
include::merge-strategies.txt[]
revert of a merge was rebuilt from scratch (i.e. rebasing and fixing,
as you seem to have interpreted), then re-merging the result without
doing anything else fancy would be the right thing to do.
+ (See the ADDENDUM below for how to rebuild a branch from scratch
+ without changing its original branching-off point.)
However, there are things to keep in mind when reverting a merge (and
reverting such a revert).
ready yet, and I really need to undo _all_ of the merge"). So then you
really should revert the merge, but when you want to re-do the merge, you
now need to do it by reverting the revert.
+
+ADDENDUM
+
+Sometimes you have to rewrite one of a topic branch's commits *and* you can't
+change the topic's branching-off point. Consider the following situation:
+
+ P---o---o---M---x---x---W---x
+ \ /
+ A---B---C
+
+where commit W reverted commit M because it turned out that commit B was wrong
+and needs to be rewritten, but you need the rewritten topic to still branch
+from commit P (perhaps P is a branching-off point for yet another branch, and
+you want be able to merge the topic into both branches).
+
+The natural thing to do in this case is to checkout the A-B-C branch and use
+"rebase -i P" to change commit B. However this does not rewrite commit A,
+because "rebase -i" by default fast-forwards over any initial commits selected
+with the "pick" command. So you end up with this:
+
+ P---o---o---M---x---x---W---x
+ \ /
+ A---B---C <-- old branch
+ \
+ B'---C' <-- naively rewritten branch
+
+To merge A-B'-C' into the mainline branch you would still have to first revert
+commit W in order to pick up the changes in A, but then it's likely that the
+changes in B' will conflict with the original B changes re-introduced by the
+reversion of W.
+
+However, you can avoid these problems if you recreate the entire branch,
+including commit A:
+
+ A'---B'---C' <-- completely rewritten branch
+ /
+ P---o---o---M---x---x---W---x
+ \ /
+ A---B---C
+
+You can merge A'-B'-C' into the mainline branch without worrying about first
+reverting W. Mainline's history would look like this:
+
+ A'---B'---C'------------------
+ / \
+ P---o---o---M---x---x---W---x---M2
+ \ /
+ A---B---C
+
+But if you don't actually need to change commit A, then you need some way to
+recreate it as a new commit with the same changes in it. The rebase commmand's
+--no-ff option provides a way to do this:
+
+ $ git rebase [-i] --no-ff P
+
+The --no-ff option creates a new branch A'-B'-C' with all-new commits (all the
+SHA IDs will be different) even if in the interactive case you only actually
+modify commit B. You can then merge this new branch directly into the mainline
+branch and be sure you'll get all of the branch's changes.
+
+You can also use --no-ff in cases where you just add extra commits to the topic
+to fix it up. Let's revisit the situation discussed at the start of this howto:
+
+ P---o---o---M---x---x---W---x
+ \ /
+ A---B---C----------------D---E <-- fixed-up topic branch
+
+At this point, you can use --no-ff to recreate the topic branch:
+
+ $ git checkout E
+ $ git rebase --no-ff P
+
+yielding
+
+ A'---B'---C'------------D'---E' <-- recreated topic branch
+ /
+ P---o---o---M---x---x---W---x
+ \ /
+ A---B---C----------------D---E
+
+You can merge the recreated branch into the mainline without reverting commit W,
+and mainline's history will look like this:
+
+ A'---B'---C'------------D'---E'
+ / \
+ P---o---o---M---x---x---W---x---M2
+ \ /
+ A---B---C
onto= rebase onto given branch instead of upstream
p,preserve-merges try to recreate merges instead of ignoring them
s,strategy= use the given merge strategy
+no-ff cherry-pick all commits, even if unchanged
m,merge always used (no-op)
i,interactive always used (no-op)
Actions:
OK_TO_SKIP_PRE_REBASE=
REBASE_ROOT=
AUTOSQUASH=
+NEVER_FF=
GIT_CHERRY_PICK_HELP=" After resolving the conflicts,
mark the corrected paths with 'git add <paths>', and
pick_one () {
ff=--ff
case "$1" in -n) sha1=$2; ff= ;; *) sha1=$1 ;; esac
+ case "$NEVER_FF" in '') ;; ?*) ff= ;; esac
output git rev-parse --verify $sha1 || die "Invalid commit name: $sha1"
test -d "$REWRITTEN" &&
pick_one_preserving_merges "$@" && return
-i)
# yeah, we know
;;
+ --no-ff)
+ NEVER_FF=t
+ ;;
--root)
REBASE_ROOT=t
;;
has_action "$TODO" ||
die_abort "Nothing to do"
- test -d "$REWRITTEN" || skip_unnecessary_picks
+ test -d "$REWRITTEN" || test -n "$NEVER_FF" || skip_unnecessary_picks
git update-ref ORIG_HEAD $HEAD
output git checkout $ONTO && do_rest
# Copyright (c) 2005 Junio C Hamano.
#
-USAGE='[--interactive | -i] [-v] [--force-rebase | -f] [--onto <newbase>] [<upstream>|--root] [<branch>] [--quiet | -q]'
+USAGE='[--interactive | -i] [-v] [--force-rebase | -f] [--no-ff] [--onto <newbase>] [<upstream>|--root] [<branch>] [--quiet | -q]'
LONG_USAGE='git-rebase replaces <branch> with a new branch of the
same name. When the --onto option is provided the new branch starts
out with a HEAD equal to <newbase>, otherwise it is equal to <upstream>
--root)
rebase_root=t
;;
- -f|--f|--fo|--for|--forc|force|--force-r|--force-re|--force-reb|--force-reba|--force-rebas|--force-rebase)
+ -f|--f|--fo|--for|--forc|force|--force-r|--force-re|--force-reb|--force-reba|--force-rebas|--force-rebase|--no-ff)
force_rebase=t
;;
--rerere-autoupdate|--no-rerere-autoupdate)
# | \
# | F - G - H (branch1)
# | \
-# \ I (branch2)
-# \
-# J - K - L - M (no-conflict-branch)
+# |\ I (branch2)
+# | \
+# | J - K - L - M (no-conflict-branch)
+# \
+# N - O - P (no-ff-branch)
#
# where A, B, D and G all touch file1, and one, two, three, four all
# touch file "conflict".
+#
+# WARNING: Modifications to the initial repository can change the SHA ID used
+# in the expect2 file for the 'stop on conflicting pick' test.
+
test_expect_success 'setup' '
test_commit A file1 &&
done &&
git checkout -b no-conflict-branch A &&
for n in J K L M
+ do
+ test_commit $n file$n
+ done &&
+ git checkout -b no-ff-branch A &&
+ for n in N O P
do
test_commit $n file$n
done
D
=======
G
->>>>>>> 51047de... G
+>>>>>>> 5d18e54... G
EOF
test_expect_success 'stop on conflicting pick' '
test_must_fail git symbolic-ref HEAD
'
+test_tick # Ensure that the rebased commits get a different timestamp.
+test_expect_success 'always cherry-pick with --no-ff' '
+ git checkout no-ff-branch &&
+ git tag original-no-ff-branch &&
+ git rebase -i --no-ff A &&
+ touch empty &&
+ for p in 0 1 2
+ do
+ test ! $(git rev-parse HEAD~$p) = $(git rev-parse original-no-ff-branch~$p) &&
+ git diff HEAD~$p original-no-ff-branch~$p > out &&
+ test_cmp empty out
+ done &&
+ test $(git rev-parse HEAD~3) = $(git rev-parse original-no-ff-branch~3) &&
+ git diff HEAD~3 original-no-ff-branch~3 > out &&
+ test_cmp empty out
+'
+
test_done