def testShuffleNoData(self):
    bucket_name = "testbucket"
    test_filename = "testfile"
    full_filename = "/%s/%s" % (bucket_name, test_filename)

    gcs_file = cloudstorage.open(full_filename, mode="w")
    gcs_file.close()

    p = shuffler.ShufflePipeline("testjob", {"bucket_name": bucket_name},
                                 [full_filename, full_filename, full_filename])
    p.start()
    test_support.execute_until_empty(self.taskqueue)

    p = shuffler.ShufflePipeline.from_id(p.pipeline_id)
    for filename in p.outputs.default.value:
      self.assertEqual(0, cloudstorage.stat(filename).st_size)
    self.assertEquals(1, len(self.emails))
dataset/ETHPy150Open GoogleCloudPlatform/appengine-mapreduce/python/test/mapreduce/shuffler_end_to_end_test.py/ShuffleEndToEndTest.testShuffleNoData/original