Autotest: Find long-failing tests.

Currently looks in the (unfiltered) database and finds all tests that
have not passed for the past 60 days.

This is a basic implementation so that further commit can be smaller in size.

BUG=chromium:247047
DEPLOY=none
TEST=There exist a set of unittests that test the core send-email or not logic.

Change-Id: I6893330cc595e308c5875408989dd40a9273f9ce
Reviewed-on: https://gerrit.chromium.org/gerrit/57237
Commit-Queue: Keyar Hood <keyar@chromium.org>
Reviewed-by: Keyar Hood <keyar@chromium.org>
Tested-by: Keyar Hood <keyar@chromium.org>
diff --git a/frontend/health/complete_failures_unittest.py b/frontend/health/complete_failures_unittest.py
new file mode 100755
index 0000000..00f9641
--- /dev/null
+++ b/frontend/health/complete_failures_unittest.py
@@ -0,0 +1,143 @@
+#!/usr/bin/python
+#
+# Copyright (c) 2013 The Chromium OS 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 datetime, unittest
+
+import mox
+
+import common, complete_failures
+from autotest_lib.client.common_lib import mail
+
+
+class EmailAboutTestFailureTests(mox.MoxTestBase):
+    """
+    Test the core logic of the comlete_failures.py script.
+
+    The core logic is to send emails only if we have not yet done so for a
+    given test before and to take actions if the test has been failing for
+    long enough.
+
+    """
+    def setUp(self):
+        super(EmailAboutTestFailureTests, self).setUp()
+
+        # We need to mock out the send function in all tests or else the
+        # emails will be sent out during tests.
+        self.mox.StubOutWithMock(mail, 'send')
+
+        self._orignal_too_late = complete_failures._DAYS_TO_BE_FAILING_TOO_LONG
+
+
+    def tearDown(self):
+        complete_failures._DAYS_TO_BE_FAILING_TOO_LONG = self._orignal_too_late
+
+
+    def test_deal_with_new_failing_test(self):
+        """
+        Test adding a failing test to the storage.
+
+        We expect the email sending code to be called if it is added.
+
+        """
+        # We will want to keep all the datetime logic intact and so we need to
+        # keep a reference to the unmocked datetime.
+        self.datetime = datetime.datetime
+        self.mox.StubOutWithMock(datetime, 'datetime')
+        datetime.datetime.today().AndReturn(self.datetime(2012, 1, 1))
+        complete_failures._DAYS_TO_BE_FAILING_TOO_LONG = 60
+
+        mail.send(
+                'chromeos-test-health@google.com',
+                ['chromeos-lab-infrastructure@google.com'],
+                [],
+                'Long Failing Tests',
+                'The following tests have been failing for at '
+                'least %i days:\n\ntest'
+                    % complete_failures._DAYS_TO_BE_FAILING_TOO_LONG)
+
+        storage = {}
+
+        # The ReplayAll is required or else a mox object sneaks its way into
+        # the storage object somehow.
+        self.mox.ReplayAll()
+        complete_failures.email_about_test_failure(
+                {'test': datetime.datetime.min}, storage)
+
+        self.assertEqual(storage['test'], self.datetime(2012, 1, 1))
+        self.mox.VerifyAll()
+
+
+    def test_remove_test_if_it_has_succeeded_recently_enough(self):
+        """Test that we remove a passing test from the storage object."""
+        storage = {'test': datetime.datetime(2012, 1, 1)}
+        complete_failures._DAYS_TO_BE_FAILING_TOO_LONG = 60
+        today = datetime.datetime(2012, 4, 10)
+        safe_date = datetime.datetime(2012, 4, 9)
+
+        self.mox.StubOutWithMock(datetime, 'datetime')
+        datetime.datetime.today().AndReturn(today)
+
+        self.mox.ReplayAll()
+        complete_failures.email_about_test_failure({'test': safe_date}, storage)
+
+        self.assertTrue('test' not in storage)
+        self.mox.VerifyAll()
+
+
+    def test_no_crashing_on_test_that_has_never_failed_for_too_long(self):
+        """Test that we do not crash for tests that have always passed."""
+        storage = {}
+        complete_failures._DAYS_TO_BE_FAILING_TOO_LONG = 60
+        today = datetime.datetime(2012,4,10)
+        safe_date = datetime.datetime(2012,4,9)
+
+        self.mox.StubOutWithMock(datetime, 'datetime')
+        datetime.datetime.today().AndReturn(today)
+
+        self.mox.ReplayAll()
+        complete_failures.email_about_test_failure({'test': safe_date}, storage)
+
+        self.assertTrue('test' not in storage)
+        self.mox.VerifyAll()
+
+
+    def test_do_not_send_email_if_test_already_in_storage(self):
+        """Test only send emails on newly problematic tests."""
+        storage = {'test': datetime.datetime(2012, 1, 1)}
+        self.datetime = datetime.datetime
+        self.mox.StubOutWithMock(datetime, 'datetime')
+        datetime.datetime.today().AndReturn(self.datetime(2012, 1, 1))
+
+        self.mox.ReplayAll()
+        complete_failures.email_about_test_failure(
+                {'test': datetime.datetime.min}, storage)
+
+        self.mox.VerifyAll()
+
+
+    def test_do_not_delete_if_still_failing(self):
+        """Test that an old failing test is not removed from storage."""
+        # We will want to keep all the datetime logic intact and so we need to
+        # keep a reference to the unmocked datetime.
+        self.datetime = datetime.datetime
+        today = datetime.datetime(2012, 1, 1)
+        self.mox.StubOutWithMock(datetime, 'datetime')
+        datetime.datetime.today().AndReturn(today)
+
+        storage = {'test': datetime.datetime.min}
+
+        # The ReplayAll is required or else a mox object sneaks its way into
+        # the storage object somehow.
+        self.mox.ReplayAll()
+        complete_failures.email_about_test_failure(
+                {'test': datetime.datetime.min}, storage)
+
+        self.assertTrue('test' in storage)
+        self.mox.VerifyAll()
+
+
+if __name__ == '__main__':
+    unittest.main()