Docserver: Cache the samples.

chrome/common/extensions/docs/server2/samples_model_test.py

 #!/usr/bin/env python
 # 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 json
 import os
 import unittest
 
+from future import Future
 from server_instance import ServerInstance
 from test_file_system import TestFileSystem
 from test_util import Server2Path
 
 
 def _ReadLocalFile(filename):
   base_path = Server2Path('test_data', 'samples_data_source')
   with open(os.path.join(base_path, filename), 'r') as f:
     return f.read()
 
 
 class _FakeCache(object):
   def __init__(self, obj):
     self._cache = obj
 
   def GetFromFileListing(self, _):
-    getter = lambda: 0
-    getter.Get = lambda: self._cache
-    return getter
+    return Future(value=self._cache)
 
 
 class SamplesModelSourceTest(unittest.TestCase):
   def setUp(self):
     server_instance = ServerInstance.ForTest(file_system=TestFileSystem({}))
     self._samples_model = server_instance.platform_bundle.GetSamplesModel(
         'apps')
     self._samples_model._samples_cache = _FakeCache(json.loads(_ReadLocalFile(
         'samples.json')))
 
   def testFilterSamples(self):
     self.assertEquals(json.loads(_ReadLocalFile('expected.json')),
-                      self._samples_model.FilterSamples('bobaloo'))
+                      self._samples_model.FilterSamples('bobaloo').Get())
 
 if __name__ == '__main__':
   unittest.main()