class CoroutineBlock(Promise):
"""Similar to go-block in core.async. Internal use only!"""
def __init__(self, gen):
super(CoroutineBlock, self).__init__()
self._gen = gen
self._last_promise = Promise()
self._last_promise.delivery(None)
processable.append(self)
@property
def parked(self):
"""Returns `True` when block parked."""
return not self._last_promise.delivered
def process(self):
"""Process promises returned by coroutine generator."""
if not self.parked:
try:
self._last_promise = self._gen.send(self._last_promise.value)
except StopIteration as e:
self.delivery(e.value)
self._close()
except AttributeError:
self.delivery(self._gen)
self._close()
def _close(self):
"""Removes self from list of active coroutine blocks."""
processable.remove(self)
def __init__(self, gen):
super(CoroutineBlock, self).__init__()
self._gen = gen
self._last_promise = Promise()
self._last_promise.delivery(None)
processable.append(self)
def test_cant_be_delivered_twice(self):
prom = Promise()
self.assertTrue(prom.delivery(12))
self.assertFalse(prom.delivery(52))
self.assertEqual(prom.value, 12)
def test_delivery(self):
prom = Promise()
self.assertTrue(prom.delivery(12))
self.assertTrue(prom.delivered)
self.assertEqual(prom.value, 12)
