def test_temp_connection_for_sender():
sig = Signal()
canary = []
receiver = lambda sender: canary.append(sender)
with sig.connected_to(receiver, sender=2):
sig.send(1)
sig.send(2)
assert canary == [2]
assert not sig.receivers
def test_temp_connection_failure():
sig = Signal()
canary = []
receiver = lambda sender: canary.append(sender)
class Failure(Exception):
pass
try:
sig.send(1)
with sig.connected_to(receiver):
sig.send(2)
raise Failure
sig.send(3)
except Failure:
pass
else:
raise AssertionError("Context manager did not propagate.")
assert canary == [2]
assert not sig.receivers
