1 files changed, 41 insertions, 0 deletions
diff --git a/t/lib-patch-mode.sh b/t/lib-patch-mode.sh
new file mode 100755
index 0000000000..75a3ee283d
--- /dev/null
+++ b/t/lib-patch-mode.sh
@@ -0,0 +1,41 @@
+. ./test-lib.sh
+
+if ! test_have_prereq PERL; then
+	say 'skipping --patch tests, perl not available'
+	test_done
+fi
+
+set_state () {
+	echo "$3" > "$1" &&
+	git add "$1" &&
+	echo "$2" > "$1"
+}
+
+save_state () {
+	noslash="$(echo "$1" | tr / _)" &&
+	cat "$1" > _worktree_"$noslash" &&
+	git show :"$1" > _index_"$noslash"
+}
+
+set_and_save_state () {
+	set_state "$@" &&
+	save_state "$1"
+}
+
+verify_state () {
+	test "$(cat "$1")" = "$2" &&
+	test "$(git show :"$1")" = "$3"
+}
+
+verify_saved_state () {
+	noslash="$(echo "$1" | tr / _)" &&
+	verify_state "$1" "$(cat _worktree_"$noslash")" "$(cat _index_"$noslash")"
+}
+
+save_head () {
+	git rev-parse HEAD > _head
+}
+
+verify_saved_head () {
+	test "$(cat _head)" = "$(git rev-parse HEAD)"
+}