Add test for device locator

Signed-off-by: Evan Lezar <elezar@nvidia.com>

internal/lookup/device_test.go

@@ -0,0 +1,55 @@
+/**
+# Copyright (c) 2022, NVIDIA CORPORATION.  All rights reserved.
+#
+# 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 lookup
+
+import (
+	"fmt"
+	"testing"
+
+	testlog "github.com/sirupsen/logrus/hooks/test"
+	"github.com/stretchr/testify/require"
+)
+
+func TestCharDeviceLocator(t *testing.T) {
+	logger, _ := testlog.NewNullLogger()
+
+	testCases := []struct {
+		root             string
+		expectedPrefixes []string
+	}{
+		{
+			root:             "",
+			expectedPrefixes: []string{"", "/dev"},
+		},
+		{
+			root:             "/",
+			expectedPrefixes: []string{"/", "/dev"},
+		},
+		{
+			root:             "/some/root",
+			expectedPrefixes: []string{"/some/root", "/some/root/dev"},
+		},
+	}
+
+	for i, tc := range testCases {
+		t.Run(fmt.Sprintf("%d", i), func(t *testing.T) {
+			f := NewCharDeviceLocator(logger, tc.root).(*file)
+
+			require.EqualValues(t, tc.expectedPrefixes, f.prefixes)
+		})
+	}
+}