cpython/Lib/test/test_asyncio/test_queues.py

527 lines
15 KiB
Python

"""Tests for queues.py"""
import asyncio
import unittest
from types import GenericAlias
def tearDownModule():
asyncio.set_event_loop_policy(None)
class QueueBasicTests(unittest.IsolatedAsyncioTestCase):
async def _test_repr_or_str(self, fn, expect_id):
"""Test Queue's repr or str.
fn is repr or str. expect_id is True if we expect the Queue's id to
appear in fn(Queue()).
"""
q = asyncio.Queue()
self.assertTrue(fn(q).startswith('<Queue'), fn(q))
id_is_present = hex(id(q)) in fn(q)
self.assertEqual(expect_id, id_is_present)
# getters
q = asyncio.Queue()
async with asyncio.TaskGroup() as tg:
# Start a task that waits to get.
getter = tg.create_task(q.get())
# Let it start waiting.
await asyncio.sleep(0)
self.assertTrue('_getters[1]' in fn(q))
# resume q.get coroutine to finish generator
q.put_nowait(0)
self.assertEqual(0, await getter)
# putters
q = asyncio.Queue(maxsize=1)
async with asyncio.TaskGroup() as tg:
q.put_nowait(1)
# Start a task that waits to put.
putter = tg.create_task(q.put(2))
# Let it start waiting.
await asyncio.sleep(0)
self.assertTrue('_putters[1]' in fn(q))
# resume q.put coroutine to finish generator
q.get_nowait()
self.assertTrue(putter.done())
q = asyncio.Queue()
q.put_nowait(1)
self.assertTrue('_queue=[1]' in fn(q))
async def test_repr(self):
await self._test_repr_or_str(repr, True)
async def test_str(self):
await self._test_repr_or_str(str, False)
def test_generic_alias(self):
q = asyncio.Queue[int]
self.assertEqual(q.__args__, (int,))
self.assertIsInstance(q, GenericAlias)
async def test_empty(self):
q = asyncio.Queue()
self.assertTrue(q.empty())
await q.put(1)
self.assertFalse(q.empty())
self.assertEqual(1, await q.get())
self.assertTrue(q.empty())
async def test_full(self):
q = asyncio.Queue()
self.assertFalse(q.full())
q = asyncio.Queue(maxsize=1)
await q.put(1)
self.assertTrue(q.full())
async def test_order(self):
q = asyncio.Queue()
for i in [1, 3, 2]:
await q.put(i)
items = [await q.get() for _ in range(3)]
self.assertEqual([1, 3, 2], items)
async def test_maxsize(self):
q = asyncio.Queue(maxsize=2)
self.assertEqual(2, q.maxsize)
have_been_put = []
async def putter():
for i in range(3):
await q.put(i)
have_been_put.append(i)
return True
t = asyncio.create_task(putter())
for i in range(2):
await asyncio.sleep(0)
# The putter is blocked after putting two items.
self.assertEqual([0, 1], have_been_put)
self.assertEqual(0, await q.get())
# Let the putter resume and put last item.
await asyncio.sleep(0)
self.assertEqual([0, 1, 2], have_been_put)
self.assertEqual(1, await q.get())
self.assertEqual(2, await q.get())
self.assertTrue(t.done())
self.assertTrue(t.result())
class QueueGetTests(unittest.IsolatedAsyncioTestCase):
async def test_blocking_get(self):
q = asyncio.Queue()
q.put_nowait(1)
self.assertEqual(1, await q.get())
async def test_get_with_putters(self):
loop = asyncio.get_running_loop()
q = asyncio.Queue(1)
await q.put(1)
waiter = loop.create_future()
q._putters.append(waiter)
self.assertEqual(1, await q.get())
self.assertTrue(waiter.done())
self.assertIsNone(waiter.result())
async def test_blocking_get_wait(self):
loop = asyncio.get_running_loop()
q = asyncio.Queue()
started = asyncio.Event()
finished = False
async def queue_get():
nonlocal finished
started.set()
res = await q.get()
finished = True
return res
queue_get_task = asyncio.create_task(queue_get())
await started.wait()
self.assertFalse(finished)
loop.call_later(0.01, q.put_nowait, 1)
res = await queue_get_task
self.assertTrue(finished)
self.assertEqual(1, res)
def test_nonblocking_get(self):
q = asyncio.Queue()
q.put_nowait(1)
self.assertEqual(1, q.get_nowait())
def test_nonblocking_get_exception(self):
q = asyncio.Queue()
self.assertRaises(asyncio.QueueEmpty, q.get_nowait)
async def test_get_cancelled_race(self):
q = asyncio.Queue()
t1 = asyncio.create_task(q.get())
t2 = asyncio.create_task(q.get())
await asyncio.sleep(0)
t1.cancel()
await asyncio.sleep(0)
self.assertTrue(t1.done())
await q.put('a')
await asyncio.sleep(0)
self.assertEqual('a', await t2)
async def test_get_with_waiting_putters(self):
q = asyncio.Queue(maxsize=1)
asyncio.create_task(q.put('a'))
asyncio.create_task(q.put('b'))
self.assertEqual(await q.get(), 'a')
self.assertEqual(await q.get(), 'b')
async def test_why_are_getters_waiting(self):
async def consumer(queue, num_expected):
for _ in range(num_expected):
await queue.get()
async def producer(queue, num_items):
for i in range(num_items):
await queue.put(i)
producer_num_items = 5
q = asyncio.Queue(1)
async with asyncio.TaskGroup() as tg:
tg.create_task(producer(q, producer_num_items))
tg.create_task(consumer(q, producer_num_items))
async def test_cancelled_getters_not_being_held_in_self_getters(self):
queue = asyncio.Queue(maxsize=5)
with self.assertRaises(TimeoutError):
await asyncio.wait_for(queue.get(), 0.1)
self.assertEqual(len(queue._getters), 0)
class QueuePutTests(unittest.IsolatedAsyncioTestCase):
async def test_blocking_put(self):
q = asyncio.Queue()
# No maxsize, won't block.
await q.put(1)
self.assertEqual(1, await q.get())
async def test_blocking_put_wait(self):
q = asyncio.Queue(maxsize=1)
started = asyncio.Event()
finished = False
async def queue_put():
nonlocal finished
started.set()
await q.put(1)
await q.put(2)
finished = True
loop = asyncio.get_running_loop()
loop.call_later(0.01, q.get_nowait)
queue_put_task = asyncio.create_task(queue_put())
await started.wait()
self.assertFalse(finished)
await queue_put_task
self.assertTrue(finished)
def test_nonblocking_put(self):
q = asyncio.Queue()
q.put_nowait(1)
self.assertEqual(1, q.get_nowait())
async def test_get_cancel_drop_one_pending_reader(self):
q = asyncio.Queue()
reader = asyncio.create_task(q.get())
await asyncio.sleep(0)
q.put_nowait(1)
q.put_nowait(2)
reader.cancel()
try:
await reader
except asyncio.CancelledError:
# try again
reader = asyncio.create_task(q.get())
await reader
result = reader.result()
# if we get 2, it means 1 got dropped!
self.assertEqual(1, result)
async def test_get_cancel_drop_many_pending_readers(self):
q = asyncio.Queue()
async with asyncio.TaskGroup() as tg:
reader1 = tg.create_task(q.get())
reader2 = tg.create_task(q.get())
reader3 = tg.create_task(q.get())
await asyncio.sleep(0)
q.put_nowait(1)
q.put_nowait(2)
reader1.cancel()
with self.assertRaises(asyncio.CancelledError):
await reader1
await reader3
# It is undefined in which order concurrent readers receive results.
self.assertEqual({reader2.result(), reader3.result()}, {1, 2})
async def test_put_cancel_drop(self):
q = asyncio.Queue(1)
q.put_nowait(1)
# putting a second item in the queue has to block (qsize=1)
writer = asyncio.create_task(q.put(2))
await asyncio.sleep(0)
value1 = q.get_nowait()
self.assertEqual(value1, 1)
writer.cancel()
try:
await writer
except asyncio.CancelledError:
# try again
writer = asyncio.create_task(q.put(2))
await writer
value2 = q.get_nowait()
self.assertEqual(value2, 2)
self.assertEqual(q.qsize(), 0)
def test_nonblocking_put_exception(self):
q = asyncio.Queue(maxsize=1, )
q.put_nowait(1)
self.assertRaises(asyncio.QueueFull, q.put_nowait, 2)
async def test_float_maxsize(self):
q = asyncio.Queue(maxsize=1.3, )
q.put_nowait(1)
q.put_nowait(2)
self.assertTrue(q.full())
self.assertRaises(asyncio.QueueFull, q.put_nowait, 3)
q = asyncio.Queue(maxsize=1.3, )
await q.put(1)
await q.put(2)
self.assertTrue(q.full())
async def test_put_cancelled(self):
q = asyncio.Queue()
async def queue_put():
await q.put(1)
return True
t = asyncio.create_task(queue_put())
self.assertEqual(1, await q.get())
self.assertTrue(t.done())
self.assertTrue(t.result())
async def test_put_cancelled_race(self):
q = asyncio.Queue(maxsize=1)
put_a = asyncio.create_task(q.put('a'))
put_b = asyncio.create_task(q.put('b'))
put_c = asyncio.create_task(q.put('X'))
await asyncio.sleep(0)
self.assertTrue(put_a.done())
self.assertFalse(put_b.done())
put_c.cancel()
await asyncio.sleep(0)
self.assertTrue(put_c.done())
self.assertEqual(q.get_nowait(), 'a')
await asyncio.sleep(0)
self.assertEqual(q.get_nowait(), 'b')
await put_b
async def test_put_with_waiting_getters(self):
q = asyncio.Queue()
t = asyncio.create_task(q.get())
await asyncio.sleep(0)
await q.put('a')
self.assertEqual(await t, 'a')
async def test_why_are_putters_waiting(self):
queue = asyncio.Queue(2)
async def putter(item):
await queue.put(item)
async def getter():
await asyncio.sleep(0)
num = queue.qsize()
for _ in range(num):
queue.get_nowait()
async with asyncio.TaskGroup() as tg:
tg.create_task(getter())
tg.create_task(putter(0))
tg.create_task(putter(1))
tg.create_task(putter(2))
tg.create_task(putter(3))
async def test_cancelled_puts_not_being_held_in_self_putters(self):
# Full queue.
queue = asyncio.Queue(maxsize=1)
queue.put_nowait(1)
# Task waiting for space to put an item in the queue.
put_task = asyncio.create_task(queue.put(1))
await asyncio.sleep(0)
# Check that the putter is correctly removed from queue._putters when
# the task is canceled.
self.assertEqual(len(queue._putters), 1)
put_task.cancel()
with self.assertRaises(asyncio.CancelledError):
await put_task
self.assertEqual(len(queue._putters), 0)
async def test_cancelled_put_silence_value_error_exception(self):
# Full Queue.
queue = asyncio.Queue(1)
queue.put_nowait(1)
# Task waiting for space to put a item in the queue.
put_task = asyncio.create_task(queue.put(1))
await asyncio.sleep(0)
# get_nowait() remove the future of put_task from queue._putters.
queue.get_nowait()
# When canceled, queue.put is going to remove its future from
# self._putters but it was removed previously by queue.get_nowait().
put_task.cancel()
# The ValueError exception triggered by queue._putters.remove(putter)
# inside queue.put should be silenced.
# If the ValueError is silenced we should catch a CancelledError.
with self.assertRaises(asyncio.CancelledError):
await put_task
class LifoQueueTests(unittest.IsolatedAsyncioTestCase):
async def test_order(self):
q = asyncio.LifoQueue()
for i in [1, 3, 2]:
await q.put(i)
items = [await q.get() for _ in range(3)]
self.assertEqual([2, 3, 1], items)
class PriorityQueueTests(unittest.IsolatedAsyncioTestCase):
async def test_order(self):
q = asyncio.PriorityQueue()
for i in [1, 3, 2]:
await q.put(i)
items = [await q.get() for _ in range(3)]
self.assertEqual([1, 2, 3], items)
class _QueueJoinTestMixin:
q_class = None
def test_task_done_underflow(self):
q = self.q_class()
self.assertRaises(ValueError, q.task_done)
async def test_task_done(self):
q = self.q_class()
for i in range(100):
q.put_nowait(i)
accumulator = 0
# Two workers get items from the queue and call task_done after each.
# Join the queue and assert all items have been processed.
running = True
async def worker():
nonlocal accumulator
while running:
item = await q.get()
accumulator += item
q.task_done()
async with asyncio.TaskGroup() as tg:
tasks = [tg.create_task(worker())
for index in range(2)]
await q.join()
self.assertEqual(sum(range(100)), accumulator)
# close running generators
running = False
for i in range(len(tasks)):
q.put_nowait(0)
async def test_join_empty_queue(self):
q = self.q_class()
# Test that a queue join()s successfully, and before anything else
# (done twice for insurance).
await q.join()
await q.join()
async def test_format(self):
q = self.q_class()
self.assertEqual(q._format(), 'maxsize=0')
q._unfinished_tasks = 2
self.assertEqual(q._format(), 'maxsize=0 tasks=2')
class QueueJoinTests(_QueueJoinTestMixin, unittest.IsolatedAsyncioTestCase):
q_class = asyncio.Queue
class LifoQueueJoinTests(_QueueJoinTestMixin, unittest.IsolatedAsyncioTestCase):
q_class = asyncio.LifoQueue
class PriorityQueueJoinTests(_QueueJoinTestMixin, unittest.IsolatedAsyncioTestCase):
q_class = asyncio.PriorityQueue
if __name__ == '__main__':
unittest.main()