diff --git a/cc/config/tidy_test.go b/cc/config/tidy_test.go
new file mode 100644
index 0000000..4ed8b23
--- /dev/null
+++ b/cc/config/tidy_test.go
@@ -0,0 +1,41 @@
+// Copyright 2016 Google Inc. 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 config
+
+import (
+	"testing"
+)
+
+func TestTidyChecksForDir(t *testing.T) {
+	testCases := []struct {
+		input    string
+		expected string
+	}{
+		{"foo/bar", tidyDefault},
+		{"vendor/foo/bar", tidyExternalVendor},
+		{"vendor/google", tidyDefault},
+		{"vendor/google/foo", tidyDefault},
+		{"vendor/google_devices/foo", tidyExternalVendor},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.input, func(t *testing.T) {
+			output := TidyChecksForDir(testCase.input)
+			if output != testCase.expected {
+				t.Error("Output doesn't match expected", output, testCase.expected)
+			}
+		})
+	}
+}