cpython/Lib/test/test_asyncio/test_runners.py

180 lines
4.9 KiB
Python

import asyncio
import unittest
from unittest import mock
from . import utils as test_utils
class TestPolicy(asyncio.AbstractEventLoopPolicy):
def __init__(self, loop_factory):
self.loop_factory = loop_factory
self.loop = None
def get_event_loop(self):
# shouldn't ever be called by asyncio.run()
raise RuntimeError
def new_event_loop(self):
return self.loop_factory()
def set_event_loop(self, loop):
if loop is not None:
# we want to check if the loop is closed
# in BaseTest.tearDown
self.loop = loop
class BaseTest(unittest.TestCase):
def new_loop(self):
loop = asyncio.BaseEventLoop()
loop._process_events = mock.Mock()
loop._selector = mock.Mock()
loop._selector.select.return_value = ()
loop.shutdown_ag_run = False
async def shutdown_asyncgens():
loop.shutdown_ag_run = True
loop.shutdown_asyncgens = shutdown_asyncgens
return loop
def setUp(self):
super().setUp()
policy = TestPolicy(self.new_loop)
asyncio.set_event_loop_policy(policy)
def tearDown(self):
policy = asyncio.get_event_loop_policy()
if policy.loop is not None:
self.assertTrue(policy.loop.is_closed())
self.assertTrue(policy.loop.shutdown_ag_run)
asyncio.set_event_loop_policy(None)
super().tearDown()
class RunTests(BaseTest):
def test_asyncio_run_return(self):
async def main():
await asyncio.sleep(0)
return 42
self.assertEqual(asyncio.run(main()), 42)
def test_asyncio_run_raises(self):
async def main():
await asyncio.sleep(0)
raise ValueError('spam')
with self.assertRaisesRegex(ValueError, 'spam'):
asyncio.run(main())
def test_asyncio_run_only_coro(self):
for o in {1, lambda: None}:
with self.subTest(obj=o), \
self.assertRaisesRegex(ValueError,
'a coroutine was expected'):
asyncio.run(o)
def test_asyncio_run_debug(self):
async def main(expected):
loop = asyncio.get_event_loop()
self.assertIs(loop.get_debug(), expected)
asyncio.run(main(False))
asyncio.run(main(True), debug=True)
def test_asyncio_run_from_running_loop(self):
async def main():
coro = main()
try:
asyncio.run(coro)
finally:
coro.close() # Suppress ResourceWarning
with self.assertRaisesRegex(RuntimeError,
'cannot be called from a running'):
asyncio.run(main())
def test_asyncio_run_cancels_hanging_tasks(self):
lo_task = None
async def leftover():
await asyncio.sleep(0.1)
async def main():
nonlocal lo_task
lo_task = asyncio.create_task(leftover())
return 123
self.assertEqual(asyncio.run(main()), 123)
self.assertTrue(lo_task.done())
def test_asyncio_run_reports_hanging_tasks_errors(self):
lo_task = None
call_exc_handler_mock = mock.Mock()
async def leftover():
try:
await asyncio.sleep(0.1)
except asyncio.CancelledError:
1 / 0
async def main():
loop = asyncio.get_running_loop()
loop.call_exception_handler = call_exc_handler_mock
nonlocal lo_task
lo_task = asyncio.create_task(leftover())
return 123
self.assertEqual(asyncio.run(main()), 123)
self.assertTrue(lo_task.done())
call_exc_handler_mock.assert_called_with({
'message': test_utils.MockPattern(r'asyncio.run.*shutdown'),
'task': lo_task,
'exception': test_utils.MockInstanceOf(ZeroDivisionError)
})
def test_asyncio_run_closes_gens_after_hanging_tasks_errors(self):
spinner = None
lazyboy = None
class FancyExit(Exception):
pass
async def fidget():
while True:
yield 1
await asyncio.sleep(1)
async def spin():
nonlocal spinner
spinner = fidget()
try:
async for the_meaning_of_life in spinner: # NoQA
pass
except asyncio.CancelledError:
1 / 0
async def main():
loop = asyncio.get_running_loop()
loop.call_exception_handler = mock.Mock()
nonlocal lazyboy
lazyboy = asyncio.create_task(spin())
raise FancyExit
with self.assertRaises(FancyExit):
asyncio.run(main())
self.assertTrue(lazyboy.done())
self.assertIsNone(spinner.ag_frame)
self.assertFalse(spinner.ag_running)