def test_get_contents_of_nonexistent_filename(self, MockClient):
bucket = Mock()
bucket.get_key.return_value = None
client = Mock()
client.bucket.return_value = bucket
MockClient.return_value = client
ImageTruck.contents_of_filename('x')
def test_get_contents_of_filename(self, MockClient):
key = Mock()
key.get_contents_as_string.return_value = 'cow innards'
bucket = Mock()
bucket.get_key.return_value = key
client = Mock()
client.bucket.return_value = bucket
MockClient.return_value = client
contents = ImageTruck.contents_of_filename('deadbeef')
eq_(contents, 'cow innards')
bucket.get_key.assert_called_with('deadbeef')
