def test_backpressure_connect_empty_stream():
@Stream.register_api()
class from_list(Stream):
def __init__(self, source, **kwargs):
self.source = source
super().__init__(ensure_io_loop=True, **kwargs)
def start(self):
self.stopped = False
self.loop.add_callback(self.run)
@gen.coroutine
def run(self):
while not self.stopped and len(self.source) > 0:
yield self._emit(self.source.pop(0))
source_list = [0, 1, 2, 3, 4]
source = Stream.from_list(source_list)
sout = Stream()
L = sout.rate_limit(1).sink_to_list()
source.connect(sout)
source.start()
wait_for(lambda: L == [0], 0.01)
assert len(source_list) > 0
def test_rate_limit():
source = Stream()
L = source.rate_limit(0.05).sink_to_list()
start = time()
for i in range(5):
yield source.emit(i)
stop = time()
assert stop - start > 0.2
assert len(L) == 5
