add test

Signed-off-by: 蓝宝石的傻话 <[email protected]>

Author: mickeyzzc

pkg/options/types_test.go

@@ -165,6 +165,11 @@ func TestNodeFieldSelector(t *testing.T) {
 			Desc:   "with node name",
 			Wanted: "",
 		},
+		{
+			Desc:   "with node name",
+			Node:   nil,
+			Wanted: "",
+		},
 		{
 			Desc: "empty node name",
 			Node: NodeType(