# Copyright (c) 2005 Junio C Hamano
#
-. git-sh-setup || die "Not a git archive"
+
+USAGE='[-n] [--no-commit] [-s <strategy>]... <merge-message> <head> <remote>+'
+. git-sh-setup
LF='
'
-usage () {
- die "git-merge [-n] [-s <strategy>]... <merge-message> <head> <remote>+"
-}
+all_strategies='recursive octopus resolve stupid ours'
+default_twohead_strategies='recursive'
+default_octopus_strategies='octopus'
+no_trivial_merge_strategies='ours'
+use_strategies=
-# all_strategies='resolve fredrik stupid octopus'
+index_merge=t
+if test "@@NO_PYTHON@@"; then
+ all_strategies='resolve octopus stupid ours'
+ default_twohead_strategies='resolve'
+fi
-all_strategies='fredrik octopus resolve stupid'
-default_strategies='resolve octopus'
-use_strategies=
+dropsave() {
+ rm -f -- "$GIT_DIR/MERGE_HEAD" "$GIT_DIR/MERGE_MSG" \
+ "$GIT_DIR/MERGE_SAVE" || exit 1
+}
-dropheads() {
- rm -f -- "$GIT_DIR/MERGE_HEAD" || exit 1
+savestate() {
+ # Stash away any local modifications.
+ git-diff-index -z --name-only $head |
+ cpio -0 -o >"$GIT_DIR/MERGE_SAVE"
}
-summary() {
+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
+}
+
+finish () {
+ test '' = "$2" || echo "$2"
+ case "$merge_msg" in
+ '')
+ echo "No merge message -- not updating HEAD"
+ ;;
+ *)
+ git-update-ref HEAD "$1" "$head" || exit 1
+ ;;
+ esac
+
case "$no_summary" in
'')
- git-diff-tree -p -M $head "$1" |
- git-apply --stat --summary
+ git-diff-tree -p --stat --summary -M "$head" "$1"
;;
esac
}
-n|--n|--no|--no-|--no-s|--no-su|--no-sum|--no-summ|\
--no-summa|--no-summar|--no-summary)
no_summary=t ;;
+ --no-c|--no-co|--no-com|--no-comm|--no-commi|--no-commit)
+ no_commit=t ;;
-s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
--strateg=*|--strategy=*|\
-s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
case "$#,$1" in
*,*=*)
strategy=`expr "$1" : '-[^=]*=\(.*\)'` ;;
- 0,*)
+ 1,*)
usage ;;
*)
strategy="$2"
shift
done
-case "$use_strategies" in
-'')
- use_strategies=$default_strategies
- ;;
-esac
-test "$#" -le 2 && usage ;# we need at least two heads.
-
merge_msg="$1"
shift
+head_arg="$1"
head=$(git-rev-parse --verify "$1"^0) || usage
shift
# All the rest are remote heads
+test "$#" = 0 && usage ;# we need at least one remote head.
+
+remoteheads=
for remote
do
- git-rev-parse --verify "$remote"^0 >/dev/null ||
+ remotehead=$(git-rev-parse --verify "$remote"^0) ||
die "$remote - not something we can merge"
+ remoteheads="${remoteheads}$remotehead "
+done
+set x $remoteheads ; shift
+
+case "$use_strategies" in
+'')
+ case "$#" in
+ 1)
+ use_strategies="$default_twohead_strategies" ;;
+ *)
+ use_strategies="$default_octopus_strategies" ;;
+ esac
+ ;;
+esac
+
+for s in $use_strategies
+do
+ case " $s " in
+ *" $no_trivial_merge_strategies "*)
+ index_merge=f
+ break
+ ;;
+ esac
done
-common=$(git-show-branch --merge-base $head "$@")
+case "$#" in
+1)
+ common=$(git-merge-base --all $head "$@")
+ ;;
+*)
+ common=$(git-show-branch --merge-base $head "$@")
+ ;;
+esac
echo "$head" >"$GIT_DIR/ORIG_HEAD"
-case "$#,$common" in
-*,'')
- die "Unable to find common commit between $head and $*"
+case "$index_merge,$#,$common,$no_commit" in
+f,*)
+ # We've been told not to try anything clever. Skip to real merge.
+ ;;
+?,*,'',*)
+ # No common ancestors found. We need a real merge.
;;
-1,"$1")
+?,1,"$1",*)
# If head can reach all the merge then we are up to date.
- # but first the most common case of merging one remote
- echo "Already up-to-date. Yeeah!"
- dropheads
+ # but first the most common case of merging one remote.
+ echo "Already up-to-date."
+ dropsave
exit 0
;;
-1,"$head")
+?,1,"$head",*)
# Again the most common case of merging one remote.
- echo "Updating from $head to $1."
+ 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"
- summary "$1"
- dropheads
+ new_head=$(git-rev-parse --verify "$1^0") &&
+ git-read-tree -u -v -m $head "$new_head" &&
+ finish "$new_head" "Fast forward"
+ dropsave
exit 0
;;
-1,*)
+?,1,?*"$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.
+ git var GIT_COMMITTER_IDENT >/dev/null || exit
+
+ echo "Trying really trivial in-index merge..."
+ git-update-index --refresh 2>/dev/null
+ if git-read-tree --trivial -m -u -v $common $head "$1" &&
+ result_tree=$(git-write-tree)
+ then
+ echo "Wonderful."
+ result_commit=$(
+ echo "$merge_msg" |
+ git-commit-tree $result_tree -p HEAD -p "$1"
+ ) || exit
+ finish "$result_commit" "In-index merge"
+ dropsave
+ exit 0
+ fi
+ echo "Nope."
+ ;;
*)
# An octopus. If we can reach all the remote we are up to date.
up_to_date=t
for remote
do
- common_one=$(git-merge-base $head $remote)
+ common_one=$(git-merge-base --all $head $remote)
if test "$common_one" != "$remote"
then
up_to_date=f
if test "$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.
+# We are going to make a new commit.
+git var GIT_COMMITTER_IDENT >/dev/null || exit
-git-update-index --refresh &&
-test '' = "`git-diff-index --cached --name-only $head`" || {
- die "Need real merge but the working tree has local changes."
-}
+# 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 $head commit. The strategies are responsible to ensure this.
+
+case "$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=
+merge_was_ok=
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" "$@"
+ exit=$?
+ if test "$no_commit" = t && test "$exit" = 0
+ then
+ merge_was_ok=t
+ exit=1 ;# pretend it left conflicts.
+ fi
+
+ test "$exit" = 0 || {
# The backend exits with 1 when conflicts are left to be resolved,
# with 2 when it does not handle the given merge at all.
- exit=$?
if test "$exit" -eq 1
then
cnt=`{
# auto resolved the merge cleanly.
if test '' != "$result_tree"
then
- parents="-p $head"
- for remote
- do
- parents="$parents -p $remote"
- done
- result_commit=$(echo "$merge_msg" | git-commit-tree $result_tree $parents)
- echo "Committed merge $result_commit, made by $wt_strategy."
- echo $result_commit >"$GIT_DIR/HEAD"
- summary $result_commit
- dropheads
+ parents=$(git-show-branch --independent "$head" "$@" | sed -e 's/^/-p /')
+ result_commit=$(echo "$merge_msg" | git-commit-tree $result_tree $parents) || exit
+ finish "$result_commit" "Merge $result_commit, made by $wt_strategy."
+ dropsave
exit 0
fi
# Pick the result from the best strategy and have the user fix it up.
case "$best_strategy" in
'')
- git reset --hard $head
- die "No merge strategy handled the merge."
+ restorestate
+ echo >&2 "No merge strategy handled the merge."
+ exit 2
;;
"$wt_strategy")
# We already have its result in the working tree.
;;
*)
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"
-die "Automatic merge failed; fix up by hand"
+echo "$merge_msg" >"$GIT_DIR/MERGE_MSG"
+
+if test "$merge_was_ok" = t
+then
+ echo >&2 \
+ "Automatic merge went well; stopped before committing as requested"
+ exit 0
+else
+ {
+ echo '
+Conflicts:
+'
+ git ls-files --unmerged |
+ sed -e 's/^[^ ]* / /' |
+ uniq
+ } >>"$GIT_DIR/MERGE_MSG"
+ if test -d "$GIT_DIR/rr-cache"
+ then
+ git-rerere
+ fi
+ die "Automatic merge failed; fix conflicts and then commit the result."
+fi