If you are using #gdunit4 and struggle asserting signals - make sure to use the exact same amount of variables when asserting. Otherwise the assert will always timeout.
class emitter:
signal test(a,b)
e = monitor_signals(emitter.new())
# exact values
e.test.emit(1,2)
assert_signal(e).is_emitted(e.test,1,2)
# any values
e.test.emit(1,2)
assert_signal(e).is_emitted(e.test,any(),any())
# timeout
e.test.emit(1,2)
assert_signal(e).is_emitted(e.test)
