def test_start_heartbeat_interval(self): c = Mock() c.timer = Mock() c.event_dispatcher = Mock() with patch('celery.worker.heartbeat.Heart') as hcls: h = Heart(c, False, 20) assert h.enabled assert h.heartbeat_interval == 20 assert c.heart is None h.start(c) assert c.heart hcls.assert_called_with(c.timer, c.event_dispatcher, h.heartbeat_interval) c.heart.start.assert_called_with()