[telemetry] OutputFormatter for unit tests.

tools/telemetry/telemetry/unittest/output_formatter_unittest.py

Index: tools/telemetry/telemetry/unittest/output_formatter_unittest.py
diff --git a/tools/telemetry/telemetry/unittest/output_formatter_unittest.py b/tools/telemetry/telemetry/unittest/output_formatter_unittest.py
new file mode 100644
index 0000000000000000000000000000000000000000..571062b9827d54f0db16aa17dfe210b78372cdc8
--- /dev/null
+++ b/tools/telemetry/telemetry/unittest/output_formatter_unittest.py
@@ -0,0 +1,54 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import unittest
+
+from telemetry.unittest import output_formatter
+
+
+class TestFoo(unittest.TestCase):
+  # Test method doesn't have test- prefix intentionally. This is so that
+  # run_test script won't run this test.
+  def RunPassingTest(self):
+    pass
+
+  def RunFailingTest(self):
+    self.fail('expected failure')
+
+
+class LoggingOutputFormatter(object):
+  def __init__(self):
+    self._call_log = []
+
+  @property
+  def call_log(self):
+    return tuple(self._call_log)
+
+  def __getattr__(self, name):
+    def wrapper(*_):
+      self._call_log.append(name)
+    return wrapper
+
+
+class OutputFormatterTest(unittest.TestCase):
+  def testTestRunner(self):
+    suite = output_formatter.TestSuite()
+    suite.addTest(TestFoo(methodName='RunPassingTest'))
+    suite.addTest(TestFoo(methodName='RunFailingTest'))
+
+    formatter = LoggingOutputFormatter()
+    runner = output_formatter.TestRunner()
+    output_formatters = (formatter,)
+    result = runner.run(suite, output_formatters, 1, None)
+
+    self.assertEqual(len(result.successes), 1)
+    self.assertEqual(len(result.failures), 1)
+    self.assertEqual(len(result.failures_and_errors), 1)
+    expected = (
+        'StartTestRun', 'StartTestSuite',
+        'StartTest', 'Success', 'StopTest',
+        'StartTest', 'Failure', 'StopTest',
+        'StopTestSuite', 'StopTestRun',
+    )
+    self.assertEqual(formatter.call_log, expected)