Move the IsMasterNode function to tests and mark it Deprecated

A future change will stop using this signal and instead use a
label selector passed on creation.

test/e2e/system/system_utils_test.go

@@ -0,0 +1,47 @@
+/*
+Copyright 2016 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 system
+
+import (
+	"testing"
+
+	"k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+func TestIsMasterNode(t *testing.T) {
+	testCases := []struct {
+		input  string
+		result bool
+	}{
+		{"foo-master", true},
+		{"foo-master-", false},
+		{"foo-master-a", false},
+		{"foo-master-ab", false},
+		{"foo-master-abc", true},
+		{"foo-master-abdc", false},
+		{"foo-bar", false},
+	}
+
+	for _, tc := range testCases {
+		node := v1.Node{ObjectMeta: metav1.ObjectMeta{Name: tc.input}}
+		res := DeprecatedMightBeMasterNode(node.Name)
+		if res != tc.result {
+			t.Errorf("case \"%s\": expected %t, got %t", tc.input, tc.result, res)
+		}
+	}
+}