fix slice.Patch with empty delta

2 files changed, 11 insertions, 0 deletions

diff --git a/slice/slice.go b/slice/slice.go
index 6d7cf10..05441c8 100644
--- a/slice/slice.go
+++ b/slice/slice.go
@@ -46,6 +46,7 @@ func Patch(source Slice, delta Delta) (target Slice) {
 		fill += len(ins.Value)
 		prev = ins.Idx + len(ins.Value)
 	}
+	copy(target[fill:], temp[tpos:])
 	return
 }
 
diff --git a/slice/slice_test.go b/slice/slice_test.go
index f6aecbc..0cf1c40 100644
--- a/slice/slice_test.go
+++ b/slice/slice_test.go
@@ -19,3 +19,13 @@ func TestPatch(t *testing.T) {
 	actual := Patch(source, patch)
 	testutils.AssertSame(t, target, actual, "Target obtained from patch application")
 }
+
+func TestEmptyPatch(t *testing.T) {
+	source := Slice{1, 2, 3, 4}
+	target := Slice{1, 2, 3, 4}
+	patch := Diff(source, target)
+	testutils.AssertSame(t, *new([]Del), patch.Del, "Patch del part")
+	testutils.AssertSame(t, *new([]Ins), patch.Ins, "Patch ins part")
+	actual := Patch(source, patch)
+	testutils.AssertSame(t, target, actual, "Target obtained from patch application")
+}