[Findit] Use unittest.mock for testing and create a shared method to mock pipeline.

appengine/findit/waterfall/test/build_failure_analysis_pipelines_test.py

Index: appengine/findit/waterfall/test/build_failure_analysis_pipelines_test.py
diff --git a/appengine/findit/waterfall/test/build_failure_analysis_pipelines_test.py b/appengine/findit/waterfall/test/build_failure_analysis_pipelines_test.py
index 9efcfb40cd2ab53ae5d13c80ae6972fc28dd426a..1b9cb9da8d0a14a47f5a8ede28b061638b096475 100644
--- a/appengine/findit/waterfall/test/build_failure_analysis_pipelines_test.py
+++ b/appengine/findit/waterfall/test/build_failure_analysis_pipelines_test.py
@@ -2,7 +2,7 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import logging
+import mock
 
 from testing_utils import testing
 
@@ -13,21 +13,6 @@ from model.wf_analysis import WfAnalysis
 from waterfall import build_failure_analysis_pipelines
 
 
-class _MockRootPipeline(object):
-  STARTED = False
-
-  def __init__(self, master_name, builder_name, build_number, build_completed,
-               force_try_job):
-    pass
-
-  def pipeline_status_path(self):
-    return ''
-
-  def start(self, queue_name):
-    _MockRootPipeline.STARTED = True
-    logging.info(queue_name)
-
-
 class BuildFailureAnalysisPipelinesTest(testing.AppengineTestCase):
   app_module = pipeline_handlers._APP
 
@@ -155,27 +140,26 @@ class BuildFailureAnalysisPipelinesTest(testing.AppengineTestCase):
 
     self.assertTrue(need_analysis)
 
-  def testStartPipelineForNewAnalysis(self):
+  @mock.patch(
+      'waterfall.build_failure_analysis_pipelines.AnalyzeBuildFailurePipeline')
+  def testStartPipelineForNewAnalysis(self, mocked_pipeline):
     master_name = 'm'
     builder_name = 'b'
     build_number = 124
 
-    self.mock(build_failure_analysis_pipelines.analyze_build_failure_pipeline,
-              'AnalyzeBuildFailurePipeline',
-              _MockRootPipeline)
-    _MockRootPipeline.STARTED = False
-
     build_failure_analysis_pipelines.ScheduleAnalysisIfNeeded(
         master_name, builder_name, build_number, failed_steps=['a'],
         build_completed=False, force=False, force_try_job=False,
         queue_name=constants.DEFAULT_QUEUE)
 
     analysis = WfAnalysis.Get(master_name, builder_name, build_number)
-
-    self.assertTrue(_MockRootPipeline.STARTED)
     self.assertIsNotNone(analysis)
+    mocked_pipeline.assert_has_calls(
+        [mock.call().start(queue_name=constants.DEFAULT_QUEUE)])
 
-  def testNotStartPipelineForNewAnalysis(self):
+  @mock.patch(
+      'waterfall.build_failure_analysis_pipelines.AnalyzeBuildFailurePipeline')
+  def testNotStartPipelineForNewAnalysis(self, mocked_pipeline):
     master_name = 'm'
     builder_name = 'b'
     build_number = 123
@@ -185,13 +169,8 @@ class BuildFailureAnalysisPipelinesTest(testing.AppengineTestCase):
         master_name, builder_name, build_number,
         not_passed_steps, analysis_status.RUNNING)
 
-    self.mock(build_failure_analysis_pipelines.analyze_build_failure_pipeline,
-              'AnalyzeBuildFailurePipeline',
-              _MockRootPipeline)
-    _MockRootPipeline.STARTED = False
-
     build_failure_analysis_pipelines.ScheduleAnalysisIfNeeded(
         master_name, builder_name, build_number, failed_steps=['a'],
         build_completed=True, force=False, queue_name=constants.DEFAULT_QUEUE)
 
-    self.assertFalse(_MockRootPipeline.STARTED)
+    self.assertFalse(mocked_pipeline.called)