Do not ignore merge options in interactive rebase

Merge strategy and its options can be specified in `git rebase`,
but with `--interactive`, they were completely ignored.

Signed-off-by: Arnaud Fontaine <arnau@debian.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-rebase--interactive.sh

@@ -80,6 +80,18 @@ amend="$state_dir"/amend
 rewritten_list="$state_dir"/rewritten-list
 rewritten_pending="$state_dir"/rewritten-pending
 
+strategy_args=
+if test -n "$do_merge"
+then
+	strategy_args=${strategy:+--strategy=$strategy}
+	eval '
+		for strategy_opt in '"$strategy_opts"'
+		do
+			strategy_args="$strategy_args -X$(git rev-parse --sq-quote "${strategy_opt#--}")"
+		done
+	'
+fi
+
 GIT_CHERRY_PICK_HELP="$resolvemsg"
 export GIT_CHERRY_PICK_HELP
 
@@ -239,7 +251,7 @@ pick_one () {
 
 	test -d "$rewritten" &&
 		pick_one_preserving_merges "$@" && return
-	output git cherry-pick $empty_args $ff "$@"
+	output eval git cherry-pick "$strategy_args" $empty_args $ff "$@"
 }
 
 pick_one_preserving_merges () {
@@ -340,9 +352,8 @@ pick_one_preserving_merges () {
 			msg_content="$(commit_message $sha1)"
 			# No point in merging the first parent, that's HEAD
 			new_parents=${new_parents# $first_parent}
-			if ! do_with_author output \
-				git merge --no-ff ${strategy:+-s $strategy} -m \
-					"$msg_content" $new_parents
+			if ! do_with_author output eval \
+			'git merge --no-ff $strategy_args -m "$msg_content" $new_parents'
 			then
 				printf "%s\n" "$msg_content" > "$GIT_DIR"/MERGE_MSG
 				die_with_patch $sha1 "Error redoing merge $sha1"
@@ -350,7 +361,7 @@ pick_one_preserving_merges () {
 			echo "$sha1 $(git rev-parse HEAD^0)" >> "$rewritten_list"
 			;;
 		*)
-			output git cherry-pick "$@" ||
+			output eval git cherry-pick "$strategy_args" "$@" ||
 				die_with_patch $sha1 "Could not pick $sha1"
 			;;
 		esac

t/t3404-rebase-interactive.sh

@@ -950,4 +950,15 @@ test_expect_success 'rebase -i, with <onto> and <upstream> specified as :/quuxer
 	git checkout branch1
 '
 
+test_expect_success 'rebase -i with --strategy and -X' '
+	git checkout -b conflict-merge-use-theirs conflict-branch &&
+	git reset --hard HEAD^ &&
+	echo five >conflict &&
+	echo Z >file1 &&
+	git commit -a -m "one file conflict" &&
+	EDITOR=true git rebase -i --strategy=recursive -Xours conflict-branch &&
+	test $(git show conflict-branch:conflict) = $(cat conflict) &&
+	test $(cat file1) = Z
+'
+
 test_done