def test_cancel_recursively():
done_order = []
fut1 = Future()
fut2 = Future()
async def some_recursion(n=10):
if not n:
await fut1
else:
await some_recursion(n - 1)
async def entry():
await some_recursion()
await fut2
sched = Scheduler()
ef = sched.run(entry())
fut1.add_done_callback(done_order.append)
ef.add_done_callback(done_order.append)
sched.tick()
ef.cancel()
sched.tick()
assert fut1.cancelled()
assert ef.cancelled()
assert done_order == [fut1, ef]
assert not fut2.cancelled()
def test_cancel_all_tasks():
async def entry():
await suspend()
assert False
sched = Scheduler()
sched.run(entry())
sched.run(entry())
sched.run(entry())
sched.cancel_all_tasks()
sched.tick()
def test_cancel_self_late():
async def entry():
await suspend()
future.cancel()
sched = Scheduler()
future = sched.run(entry())
sched.tick()
assert future.cancelled()
with pytest.raises(CancelledError):
future.result()
def test_gather():
fut1 = Future()
fut2 = Future()
fut3 = Future()
sched = Scheduler()
gf = gather(fut1, fut2, fut3, scheduler=sched)
assert not gf.done()
fut1.set_result(1)
assert not gf.done()
fut3.set_result(3)
fut2.set_result(2)
assert not gf.done()
sched.tick()
assert gf.done()
assert gf.result() == [1, 3, 2]
def test_gather_cancel():
"""
Check: If a gather() future is cancelled, all source futures are cancelled.
"""
fut1 = Future()
fut2 = Future()
fut3 = Future()
sched = Scheduler()
gf = gather(fut1, fut2, fut3, scheduler=sched)
assert not gf.done()
gf.cancel()
sched.tick()
assert fut1.cancelled()
assert fut2.cancelled()
assert fut3.cancelled()
assert gf.cancelled()
def test_cancel_done_callback():
done_called_by = None
def done(fut):
nonlocal done_called_by
done_called_by = fut
async def entry():
await suspend()
sched = Scheduler()
ef = sched.run(entry())
ef.add_done_callback(done)
ef.cancel()
sched.tick()
assert done_called_by == ef
def test_gather_exc():
fut1 = Future()
fut2 = Future()
fut3 = Future()
sched = Scheduler()
gf = gather(fut1, fut2, fut3, scheduler=sched)
assert not gf.done()
fut1.set_result(1)
assert not gf.done()
fut3.set_exception(KeyError)
assert not gf.done()
sched.tick()
assert gf.done()
# fut3 failed, so the other pending futures should enter cancelled state.
assert fut2.cancelled()
with pytest.raises(KeyError):
gf.result()
def test_loop():
f = Future()
def get_response():
return f
async def entry():
return await get_response()
sched = Scheduler()
entry_future = sched.run(entry())
sched.tick()
assert not entry_future.done()
f.set_result(666)
assert not entry_future.done()
sched.tick()
assert entry_future.done()
assert entry_future.result() == 666
def test_loop_exc():
f = Future()
def get_response():
return f
async def entry():
return await get_response()
sched = Scheduler()
entry_future = sched.run(entry())
sched.tick()
assert not entry_future.done()
f.set_exception(KeyError)
assert not entry_future.done()
sched.tick()
assert entry_future.done()
with pytest.raises(KeyError):
entry_future.result()
def test_as_completed_cancel():
"""
Check: If a source future to as_completed() completes after as_completed() is cancelled,
no crash occurs and the source future completion is ignored.
"""
source_fut = Future()
sched = Scheduler()
ac = as_completed(source_fut, scheduler=sched)
as_completed_fut = sched.run(ac.__anext__())
sched.tick()
as_completed_fut.cancel()
sched.tick()
with pytest.raises(CancelledError):
sched.run_until_complete(as_completed_fut)
source_fut.set_exception(KeyError)
sched.tick()
return future
async def waiterA():
for n in range(5):
await wait_for(500)
print('waiterA', n)
async def waiterB():
for n in range(10):
await wait_for(100)
print('waiterB', n)
async def waiterC():
await wait_for(3000)
print('Quitting.')
quit()
scheduler = Scheduler()
scheduler.run(waiterA())
scheduler.run(waiterB())
scheduler.run(waiterC())
# This is the "event loop"
while not done:
scheduler.tick()
app.processEvents(QEventLoop.AllEvents | QEventLoop.WaitForMoreEvents)