'Validate that SSC data is collected if not yet populated'

def test_get_volume_stats_no_ssc(self):

    fake_stats = {'key': 'val'}
    def populate_stats():
        self.library._stats = fake_stats
    self.library._update_volume_stats = mock.Mock(side_effect=populate_stats)
    self.library._update_ssc_info = mock.Mock()
    self.library._ssc_stats = None
    actual = self.library.get_volume_stats(refresh=True)
    self.library._update_volume_stats.assert_called_once_with()
    self.library._update_ssc_info.assert_called_once_with()
    self.assertEqual(fake_stats, actual)
