Modify PathConfig.PathSlice method and add tests

pkg/transformerconfig/transformerconfig_test.go

@@ -1,3 +1,19 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
 package transformerconfig
 
 import (
@@ -125,3 +141,10 @@ func TestMerge(t *testing.T) {
 		t.Fatalf("expected: %v\n but got: %v\n", expected, actual)
 	}
 }
+
+func TestMakeDefaultTransformerConfig(t *testing.T) {
+	_, err := MakeDefaultTransformerConfig()
+	if err != nil {
+		t.Fatalf("unexpected error %v\n", err)
+	}
+}