old_contents: # -*- coding: utf-8 -*-
  import unittest
  
  from thumbnails.backends import generate_filename, get_thumbnail
  from thumbnails.images import SourceFile, Thumbnail
  
  from .compat import mock
  
  
  class BackendTestCase(unittest.TestCase):
      def test_generate_filename(self):
          self.assertEqual(
              generate_filename(SourceFile('url'), '100x200', 'center', None),
              ['0af', 'a360db703bd5c2fe7c83843ce7738a0a6d37b']
          )
          self.assertEqual(
              generate_filename(SourceFile('url'), '200x200', 'center', None),
              ['851', '521c21fe9709802e9d4eb20a5fe84c18cd3ad']
          )
  
      @mock.patch('thumbnails.backends.cache_get', lambda x:  True)
      def test_get_thumbnail_cached(self):
          self.assertTrue(get_thumbnail('', '200'))
  
      @mock.patch('thumbnails.engines.base.ThumbnailBaseEngine.get_thumbnail')
      def test_get_thumbnail(self, mock_engine_get_thumbnail):
          thumbnail = get_thumbnail('http://puppies.lkng.me/400x600/', '200')
          self.assertTrue(mock_engine_get_thumbnail.called)
          self.assertTrue(isinstance(thumbnail, Thumbnail))
  
new_contents: # -*- coding: utf-8 -*-
  import unittest
  
  from thumbnails.backends import generate_filename, get_thumbnail
  from thumbnails.conf import settings
  from thumbnails.images import SourceFile, Thumbnail
  
  from .compat import mock
  
  
  class BackendTestCase(unittest.TestCase):
      def test_generate_filename(self):
          self.assertEqual(
              generate_filename(SourceFile('url'), '100x200', 'center', None),
              ['0af', 'a360db703bd5c2fe7c83843ce7738a0a6d37b']
          )
          self.assertEqual(
              generate_filename(SourceFile('url'), '200x200', 'center', None),
              ['851', '521c21fe9709802e9d4eb20a5fe84c18cd3ad']
          )
  
      @mock.patch('{}.get'.format(settings.THUMBNAIL_CACHE_BACKEND), lambda o, x:  True)
      def test_get_thumbnail_cached(self):
          self.assertTrue(get_thumbnail('', '200'))
  
      @mock.patch('thumbnails.engines.base.ThumbnailBaseEngine.get_thumbnail')
      def test_get_thumbnail(self, mock_engine_get_thumbnail):
          thumbnail = get_thumbnail('http://puppies.lkng.me/400x600/', '200')
          self.assertTrue(mock_engine_get_thumbnail.called)
          self.assertTrue(isinstance(thumbnail, Thumbnail))
  
subject: Fix failing mock of cache backend