def test_subscribers_get_called_on_publish():
bus = Bus()
def on_1(data):
global called_1
called_1 = True
def on_2(data):
global called_2
called_2 = True
bus.subscribe("some_message", on_1)
bus.subscribe("some_message", on_2)
bus.publish("some_message", {})
assert called_1
assert called_2
def test_can_publish_a_message_with_no_subscribers():
bus = Bus()
bus.publish("some_message", {})
def test_can_subscribe_to_a_message():
bus = Bus()
bus.subscribe("some_message", lambda: None)
assert len(bus.subscriptions) == 1