def METHOD_NAME(self):
    def value_in_conf():
        with open(os.path.join(self.p.data_dir, 'postgresql.conf')) as f:
            for line in f:
                if line.startswith('synchronous_standby_names'):
                    return line.strip()
    mock_reload = self.p.reload = Mock()
    self.s.set_synchronous_standby_names(CaseInsensitiveSet(['n1']))
    self.assertEqual(value_in_conf(), "synchronous_standby_names = 'n1'")
    mock_reload.assert_called()
    mock_reload.reset_mock()
    self.s.set_synchronous_standby_names(CaseInsensitiveSet(['n1']))
    mock_reload.assert_not_called()
    self.assertEqual(value_in_conf(), "synchronous_standby_names = 'n1'")
    self.s.set_synchronous_standby_names(CaseInsensitiveSet(['n1', 'n2']))
    mock_reload.assert_called()
    self.assertEqual(value_in_conf(), "synchronous_standby_names = '2 (n1,n2)'")
    mock_reload.reset_mock()
    self.s.set_synchronous_standby_names(CaseInsensitiveSet([]))
    mock_reload.assert_called()
    self.assertEqual(value_in_conf(), None)
    mock_reload.reset_mock()
    self.p._global_config = GlobalConfig({'synchronous_mode': True})
    self.s.set_synchronous_standby_names(CaseInsensitiveSet('*'))
    mock_reload.assert_called()
    self.assertEqual(value_in_conf(), "synchronous_standby_names = '*'")