switch system priority class to versioned (v1) api

move all the helpers to scheduling v1 helpers

less explicit conversion

pkg/apis/scheduling/v1/helpers_test.go

@@ -0,0 +1,56 @@
+/*
+Copyright 2019 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 v1
+
+import (
+	"testing"
+
+	v1 "k8s.io/api/scheduling/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/kubernetes/pkg/apis/scheduling"
+)
+
+func TestIsKnownSystemPriorityClass(t *testing.T) {
+	tests := []struct {
+		name     string
+		pc       *v1.PriorityClass
+		expected bool
+	}{
+		{
+			name:     "system priority class",
+			pc:       SystemPriorityClasses()[0],
+			expected: true,
+		},
+		{
+			name: "non-system priority class",
+			pc: &v1.PriorityClass{
+				ObjectMeta: metav1.ObjectMeta{
+					Name: scheduling.SystemNodeCritical,
+				},
+				Value:       scheduling.SystemCriticalPriority, // This is the value of system cluster critical
+				Description: "Used for system critical pods that must not be moved from their current node.",
+			},
+			expected: false,
+		},
+	}
+
+	for _, test := range tests {
+		if is, err := IsKnownSystemPriorityClass(test.pc.Name, test.pc.Value, test.pc.GlobalDefault); test.expected != is {
+			t.Errorf("Test [%v]: Expected %v, but got %v. Error: %v", test.name, test.expected, is, err)
+		}
+	}
+}