die "git-merge [-n] [-s <strategy>]... <merge-message> <head> <remote>+"
}
-# all_strategies='resolve fredrik stupid octopus'
+# all_strategies='resolve recursive stupid octopus'
-all_strategies='resolve octopus stupid'
+all_strategies='recursive octopus resolve stupid'
default_strategies='resolve octopus'
use_strategies=
-dropheads() {
- rm -f -- "$GIT_DIR/MERGE_HEAD" || exit 1
+dropsave() {
+ rm -f -- "$GIT_DIR/MERGE_HEAD" "$GIT_DIR/MERGE_MSG" \
+ "$GIT_DIR/MERGE_SAVE" || exit 1
+}
+
+savestate() {
+ # Stash away any local modifications.
+ git-diff-index -r -z --name-only $head |
+ cpio -0 -o >"$GIT_DIR/MERGE_SAVE"
+}
+
+restorestate() {
+ if test -f "$GIT_DIR/MERGE_SAVE"
+ then
+ git reset --hard $head
+ cpio -iuv <"$GIT_DIR/MERGE_SAVE"
+ git-update-index --refresh >/dev/null
+ fi
}
summary() {
case "$#,$1" in
*,*=*)
strategy=`expr "$1" : '-[^=]*=\(.*\)'` ;;
- 0,*)
+ 1,*)
usage ;;
*)
strategy="$2"
merge_msg="$1"
shift
+head_arg="$1"
head=$(git-rev-parse --verify "$1"^0) || usage
shift
case "$#,$common" in
*,'')
- die "Unable to find common commit between $head and $*"
+ # No common ancestors found. We need a real merge.
;;
1,"$1")
# If head can reach all the merge then we are up to date.
# but first the most common case of merging one remote
echo "Already up-to-date. Yeeah!"
- dropheads
+ dropsave
exit 0
;;
1,"$head")
# Again the most common case of merging one remote.
echo "Updating from $head to $1."
git-update-index --refresh 2>/dev/null
- git-read-tree -u -m $head "$1" || exit 1
- git-rev-parse --verify "$1^0" > "$GIT_DIR/HEAD"
+ git-read-tree -u -m $head "$1" &&
+ new_head=$(git-rev-parse --verify "$1^0") &&
+ git-update-ref HEAD "$new_head" "$head" || exit 1
summary "$1"
- dropheads
+ dropsave
exit 0
;;
-1,*)
+1,?*"$LF"?*)
# We are not doing octopus and not fast forward. Need a
# real merge.
;;
+1,*)
+ # We are not doing octopus, not fast forward, and have only
+ # one common. See if it is really trivial.
+ echo "Trying really trivial in-index merge..."
+ git-update-index --refresh 2>/dev/null
+ if git-read-tree --trivial -m -u $common $head "$1" &&
+ result_tree=$(git-write-tree)
+ then
+ echo "Wonderful."
+ result_commit=$(
+ echo "$merge_msg" |
+ git-commit-tree $result_tree -p HEAD -p "$1"
+ ) || exit
+ git-update-ref HEAD $result_commit $head
+ summary $result_commit
+ dropsave
+ exit 0
+ fi
+ echo "Nope."
+ ;;
*)
# An octopus. If we can reach all the remote we are up to date.
up_to_date=t
if test "$up_to_date" = t
then
echo "Already up-to-date. Yeeah!"
- dropheads
+ dropsave
exit 0
fi
;;
esac
-# At this point we need a real merge. Require that the tree matches
-# exactly our head.
+# At this point, we need a real merge. No matter what strategy
+# we use, it would operate on the index, possibly affecting the
+# working tree, and when resolved cleanly, have the desired tree
+# in the index -- this means that the index must be in sync with
+# the $head commit. The strategies are responsible to ensure this.
-git-update-index --refresh &&
-test '' = "`git-diff-index --cached --name-only $head`" || {
- die "Need real merge but the working tree has local changes."
-}
+case "$use_strategies" in
+?*' '?*)
+ # Stash away the local changes so that we can try more than one.
+ savestate
+ single_strategy=no
+ ;;
+*)
+ rm -f "$GIT_DIR/MERGE_SAVE"
+ single_strategy=yes
+ ;;
+esac
result_tree= best_cnt=-1 best_strategy= wt_strategy=
for strategy in $use_strategies
do
test "$wt_strategy" = '' || {
echo "Rewinding the tree to pristine..."
- git reset --hard $head
+ restorestate
}
- echo "Trying merge strategy $strategy..."
+ case "$single_strategy" in
+ no)
+ echo "Trying merge strategy $strategy..."
+ ;;
+ esac
+
+ # Remember which strategy left the state in the working tree
wt_strategy=$strategy
- git-merge-$strategy $common -- $head "$@" || {
+
+ git-merge-$strategy $common -- "$head_arg" "$@" || {
# The backend exits with 1 when conflicts are left to be resolved,
# with 2 when it does not handle the given merge at all.
do
parents="$parents -p $remote"
done
- result_commit=$(echo "$merge_msg" | git-commit-tree $result_tree $parents)
+ result_commit=$(echo "$merge_msg" | git-commit-tree $result_tree $parents) || exit
echo "Committed merge $result_commit, made by $wt_strategy."
- echo $result_commit >"$GIT_DIR/HEAD"
+ git-update-ref HEAD $result_commit $head
summary $result_commit
- dropheads
+ dropsave
exit 0
fi
# Pick the result from the best strategy and have the user fix it up.
case "$best_strategy" in
'')
- git reset --hard $head
+ restorestate
die "No merge strategy handled the merge."
;;
"$wt_strategy")
;;
*)
echo "Rewinding the tree to pristine..."
- git reset --hard $head
+ restorestate
echo "Using the $best_strategy to prepare resolving by hand."
- git-merge-$best_strategy $common -- $head "$@"
+ git-merge-$best_strategy $common -- "$head_arg" "$@"
;;
esac
for remote
do
echo $remote
done >"$GIT_DIR/MERGE_HEAD"
+echo $merge_msg >"$GIT_DIR/MERGE_MSG"
+
die "Automatic merge failed; fix up by hand"