git-rebase: add keep_empty flag

Add a command line switch to git-rebase to allow a user the ability to specify
that they want to keep any commits in a series that are empty.

When git-rebase's type is am, then this option will automatically keep any
commit that has a tree object identical to its parent.

This patch changes the default behavior of interactive rebases as well.  With
this patch, git-rebase -i will produce a revision set passed to
git-revision-editor, in which empty commits are commented out.  Empty commits
may be kept manually by uncommenting them.  If the new --keep-empty option is
used in an interactive rebase the empty commits will automatically all be
uncommented in the editor.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Neil Horman 2012-04-20 10:36:17 -04:00 committed by Junio C Hamano
parent bedfe86ce6
commit 90e1818f9a
4 changed files with 55 additions and 8 deletions

View file

@ -238,6 +238,10 @@ leave out at most one of A and B, in which case it defaults to HEAD.
will be reset to where it was when the rebase operation was
started.
--keep-empty::
Keep the commits that do not change anything from its
parents in the result.
--skip::
Restart the rebasing process by skipping the current patch.

View file

@ -20,11 +20,20 @@ esac
test -n "$rebase_root" && root_flag=--root
git format-patch -k --stdout --full-index --ignore-if-in-upstream \
if test -n "$keep_empty"
then
# we have to do this the hard way. git format-patch completely squashes
# empty commits and even if it didn't the format doesn't really lend
# itself well to recording empty patches. fortunately, cherry-pick
# makes this easy
git cherry-pick --allow-empty "$revisions"
else
git format-patch -k --stdout --full-index --ignore-if-in-upstream \
--src-prefix=a/ --dst-prefix=b/ \
--no-renames $root_flag "$revisions" |
git am $git_am_opt --rebasing --resolvemsg="$resolvemsg" &&
move_to_original_branch
git am $git_am_opt --rebasing --resolvemsg="$resolvemsg"
fi && move_to_original_branch
ret=$?
test 0 != $ret -a -d "$state_dir" && write_basic_state
exit $ret

View file

@ -167,6 +167,14 @@ has_action () {
sane_grep '^[^#]' "$1" >/dev/null
}
is_empty_commit() {
tree=$(git rev-parse -q --verify "$1"^{tree} 2>/dev/null ||
die "$1: not a commit that can be picked")
ptree=$(git rev-parse -q --verify "$1"^^{tree} 2>/dev/null ||
ptree=4b825dc642cb6eb9a060e54bf8d69288fbee4904)
test "$tree" = "$ptree"
}
# Run command with GIT_AUTHOR_NAME, GIT_AUTHOR_EMAIL, and
# GIT_AUTHOR_DATE exported from the current environment.
do_with_author () {
@ -191,12 +199,19 @@ git_sequence_editor () {
pick_one () {
ff=--ff
case "$1" in -n) sha1=$2; ff= ;; *) sha1=$1 ;; esac
case "$force_rebase" in '') ;; ?*) ff= ;; esac
output git rev-parse --verify $sha1 || die "Invalid commit name: $sha1"
if is_empty_commit "$sha1"
then
empty_args="--allow-empty"
fi
test -d "$rewritten" &&
pick_one_preserving_merges "$@" && return
output git cherry-pick $ff "$@"
output git cherry-pick $empty_args $ff "$@"
}
pick_one_preserving_merges () {
@ -780,9 +795,17 @@ git rev-list $merges_option --pretty=oneline --abbrev-commit \
sed -n "s/^>//p" |
while read -r shortsha1 rest
do
if test -z "$keep_empty" && is_empty_commit $shortsha1
then
comment_out="# "
else
comment_out=
fi
if test t != "$preserve_merges"
then
printf '%s\n' "pick $shortsha1 $rest" >> "$todo"
printf '%s\n' "${comment_out}pick $shortsha1 $rest" >>"$todo"
else
sha1=$(git rev-parse $shortsha1)
if test -z "$rebase_root"
@ -801,7 +824,7 @@ do
if test f = "$preserve"
then
touch "$rewritten"/$sha1
printf '%s\n' "pick $shortsha1 $rest" >> "$todo"
printf '%s\n' "${comment_out}pick $shortsha1 $rest" >>"$todo"
fi
fi
done
@ -851,6 +874,12 @@ cat >> "$todo" << EOF
#
EOF
if test -z "$keep_empty"
then
echo "# Note that empty commits are commented out" >>"$todo"
fi
has_action "$todo" ||
die_abort "Nothing to do"

View file

@ -43,6 +43,7 @@ s,strategy=! use the given merge strategy
no-ff! cherry-pick all commits, even if unchanged
m,merge! use merging strategies to rebase
i,interactive! let the user edit the list of commits to rebase
k,keep-empty preserve empty commits during rebase
f,force-rebase! force rebase even if branch is up to date
X,strategy-option=! pass the argument through to the merge strategy
stat! display a diffstat of what changed upstream
@ -97,6 +98,7 @@ state_dir=
action=
preserve_merges=
autosquash=
keep_empty=
test "$(git config --bool rebase.autosquash)" = "true" && autosquash=t
read_basic_state () {
@ -220,6 +222,9 @@ do
-i)
interactive_rebase=explicit
;;
-k)
keep_empty=yes
;;
-p)
preserve_merges=t
test -z "$interactive_rebase" && interactive_rebase=implied