import test.support
# Skip tests if _multiprocessing wasn't built.
test.support.import_module('_multiprocessing')
# Skip tests if sem_open implementation is broken.
test.support.import_module('multiprocessing.synchronize')
# import threading after _multiprocessing to raise a more relevant error
# message: "No module named _multiprocessing". _multiprocessing is not compiled
# without thread support.
test.support.import_module('threading')
from test.support.script_helper import assert_python_ok
import itertools
import os
import sys
import threading
import time
import unittest
import weakref
from concurrent import futures
from concurrent.futures._base import (
PENDING, RUNNING, CANCELLED, CANCELLED_AND_NOTIFIED, FINISHED, Future)
from concurrent.futures.process import BrokenProcessPool
def create_future(state=PENDING, exception=None, result=None):
f = Future()
f._state = state
f._exception = exception
f._result = result
return f
PENDING_FUTURE = create_future(state=PENDING)
RUNNING_FUTURE = create_future(state=RUNNING)
CANCELLED_FUTURE = create_future(state=CANCELLED)
CANCELLED_AND_NOTIFIED_FUTURE = create_future(state=CANCELLED_AND_NOTIFIED)
EXCEPTION_FUTURE = create_future(state=FINISHED, exception=OSError())
SUCCESSFUL_FUTURE = create_future(state=FINISHED, result=42)
def mul(x, y):
return x * y
def sleep_and_raise(t):
time.sleep(t)
raise Exception('this is an exception')
def sleep_and_print(t, msg):
time.sleep(t)
print(msg)
sys.stdout.flush()
class MyObject(object):
def my_method(self):
pass
def make_dummy_object(_):
return MyObject()
class BaseTestCase(unittest.TestCase):
def setUp(self):
self._thread_key = test.support.threading_setup()
def tearDown(self):
test.support.reap_children()
test.support.threading_cleanup(*self._thread_key)
class ExecutorMixin:
worker_count = 5
def setUp(self):
super().setUp()
self.t1 = time.monotonic()
try:
self.executor = self.executor_type(max_workers=self.worker_count)
except NotImplementedError as e:
self.skipTest(str(e))
self._prime_executor()
def tearDown(self):
self.executor.shutdown(wait=True)
self.executor = None
dt = time.monotonic() - self.t1
if test.support.verbose:
print("%.2fs" % dt, end=' ')
self.assertLess(dt, 300, "synchronization issue: test lasted too long")
super().tearDown()
def _prime_executor(self):
# Make sure that the executor is ready to do work before running the
# tests. This should reduce the probability of timeouts in the tests.
futures = [self.executor.submit(time.sleep, 0.1)
for _ in range(self.worker_count)]
for f in futures:
f.result()
class ThreadPoolMixin(ExecutorMixin):
executor_type = futures.ThreadPoolExecutor
class ProcessPoolMixin(ExecutorMixin):
executor_type = futures.ProcessPoolExecutor
class ExecutorShutdownTest:
def test_run_after_shutdown(self):
self.executor.shutdown()
self.assertRaises(RuntimeError,
self.executor.submit,
pow, 2, 5)
def test_interpreter_shutdown(self):
# Test the atexit hook for shutdown of worker threads and processes
rc, out, err = assert_python_ok('-c', """if 1:
from concurrent.futures import {executor_type}
from time import sleep
from test.test_concurrent_futures import sleep_and_print
t = {executor_type}(5)
t.submit(sleep_and_print, 1.0, "apple")
""".format(executor_type=self.executor_type.__name__))
# Errors in atexit hooks don't change the process exit code, check
# stderr manually.
self.assertFalse(err)
self.assertEqual(out.strip(), b"apple")
def test_hang_issue12364(self):
fs = [self.executor.submit(time.sleep, 0.1) for _ in range(50)]
self.executor.shutdown()
for f in fs:
f.result()
class ThreadPoolShutdownTest(ThreadPoolMixin, ExecutorShutdownTest, BaseTestCase):
def _prime_executor(self):
pass
def test_threads_terminate(self):
self.executor.submit(mul, 21, 2)
self.executor.submit(mul, 6, 7)
self.executor.submit(mul, 3, 14)
self.assertEqual(len(self.executor._threads), 3)
self.executor.shutdown()
for t in self.executor._threads:
t.join()
def test_context_manager_shutdown(self):
with futures.ThreadPoolExecutor(max_workers=5) as e:
executor = e
self.assertEqual(list(e.map(abs, range(-5, 5))),
[5, 4, 3, 2, 1, 0, 1, 2, 3, 4])
for t in executor._threads:
t.join()
def test_del_shutdown(self):
executor = futures.ThreadPoolExecutor(max_workers=5)
executor.map(abs, range(-5, 5))
threads = executor._threads
del executor
for t in threads:
t.join()
def test_thread_names_assigned(self):
executor = futures.ThreadPoolExecutor(
max_workers=5, thread_name_prefix='SpecialPool')
executor.map(abs, range(-5, 5))
threads = executor._threads
del executor
for t in threads:
self.assertRegex(t.name, r'^SpecialPool_[0-4]$')
t.join()
def test_thread_names_default(self):
executor = futures.ThreadPoolExecutor(max_workers=5)
executor.map(abs, range(-5, 5))
threads = executor._threads
del executor
for t in threads:
# Ensure that our default name is reasonably sane and unique when
# no thread_name_prefix was supplied.
self.assertRegex(t.name, r'ThreadPoolExecutor-\d+_[0-4]$')
t.join()
class ProcessPoolShutdownTest(ProcessPoolMixin, ExecutorShutdownTest, BaseTestCase):
def _prime_executor(self):
pass
def test_processes_terminate(self):
self.executor.submit(mul, 21, 2)
self.executor.submit(mul, 6, 7)
self.executor.submit(mul, 3, 14)
self.assertEqual(len(self.executor._processes), 5)
processes = self.executor._processes
self.executor.shutdown()
for p in processes.values():
p.join()
def test_context_manager_shutdown(self):
with futures.ProcessPoolExecutor(max_workers=5) as e:
processes = e._processes
self.assertEqual(list(e.map(abs, range(-5, 5))),
[5, 4, 3, 2, 1, 0, 1, 2, 3, 4])
for p in processes.values():
p.join()
def test_del_shutdown(self):
executor = futures.ProcessPoolExecutor(max_workers=5)
list(executor.map(abs, range(-5, 5)))
queue_management_thread = executor._queue_management_thread
processes = executor._processes
call_queue = executor._call_queue
del executor
queue_management_thread.join()
for p in processes.values():
p.join()
call_queue.close()
call_queue.join_thread()
class WaitTests:
def test_first_completed(self):
future1 = self.executor.submit(mul, 21, 2)
future2 = self.executor.submit(time.sleep, 1.5)
done, not_done = futures.wait(
[CANCELLED_FUTURE, future1, future2],
return_when=futures.FIRST_COMPLETED)
self.assertEqual(set([future1]), done)
self.assertEqual(set([CANCELLED_FUTURE, future2]), not_done)
def test_first_completed_some_already_completed(self):
future1 = self.executor.submit(time.sleep, 1.5)
finished, pending = futures.wait(
[CANCELLED_AND_NOTIFIED_FUTURE, SUCCESSFUL_FUTURE, future1],
return_when=futures.FIRST_COMPLETED)
self.assertEqual(
set([CANCELLED_AND_NOTIFIED_FUTURE, SUCCESSFUL_FUTURE]),
finished)
self.assertEqual(set([future1]), pending)
def test_first_exception(self):
future1 = self.executor.submit(mul, 2, 21)
future2 = self.executor.submit(sleep_and_raise, 1.5)
future3 = self.executor.submit(time.sleep, 3)
finished, pending = futures.wait(
[future1, future2, future3],
return_when=futures.FIRST_EXCEPTION)
self.assertEqual(set([future1, future2]), finished)
self.assertEqual(set([future3]), pending)
def test_first_exception_some_already_complete(self):
future1 = self.executor.submit(divmod, 21, 0)
future2 = self.executor.submit(time.sleep, 1.5)
finished, pending = futures.wait(
[SUCCESSFUL_FUTURE,
CANCELLED_FUTURE,
CANCELLED_AND_NOTIFIED_FUTURE,
future1, future2],
return_when=futures.FIRST_EXCEPTION)
self.assertEqual(set([SUCCESSFUL_FUTURE,
CANCELLED_AND_NOTIFIED_FUTURE,
future1]), finished)
self.assertEqual(set([CANCELLED_FUTURE, future2]), pending)
def test_first_exception_one_already_failed(self):
future1 = self.executor.submit(time.sleep, 2)
finished, pending = futures.wait(
[EXCEPTION_FUTURE, future1],
return_when=futures.FIRST_EXCEPTION)
self.assertEqual(set([EXCEPTION_FUTURE]), finished)
self.assertEqual(set([future1]), pending)
def test_all_completed(self):
future1 = self.executor.submit(divmod, 2, 0)
future2 = self.executor.submit(mul, 2, 21)
finished, pending = futures.wait(
[SUCCESSFUL_FUTURE,
CANCELLED_AND_NOTIFIED_FUTURE,
EXCEPTION_FUTURE,
future1,
future2],
return_when=futures.ALL_COMPLETED)
self.assertEqual(set([SUCCESSFUL_FUTURE,
CANCELLED_AND_NOTIFIED_FUTURE,
EXCEPTION_FUTURE,
future1,
future2]), finished)
self.assertEqual(set(), pending)
def test_timeout(self):
future1 = self.executor.submit(mul, 6, 7)
future2 = self.executor.submit(time.sleep, 6)
finished, pending = futures.wait(
[CANCELLED_AND_NOTIFIED_FUTURE,
EXCEPTION_FUTURE,
SUCCESSFUL_FUTURE,
future1, future2],
timeout=5,
return_when=futures.ALL_COMPLETED)
self.assertEqual(set([CANCELLED_AND_NOTIFIED_FUTURE,
EXCEPTION_FUTURE,
SUCCESSFUL_FUTURE,
future1]), finished)
self.assertEqual(set([future2]), pending)
class ThreadPoolWaitTests(ThreadPoolMixin, WaitTests, BaseTestCase):
def test_pending_calls_race(self):
# Issue #14406: multi-threaded race condition when waiting on all
# futures.
event = threading.Event()
def future_func():
event.wait()
oldswitchinterval = sys.getswitchinterval()
sys.setswitchinterval(1e-6)
try:
fs = {self.executor.submit(future_func) for i in range(100)}
event.set()
futures.wait(fs, return_when=futures.ALL_COMPLETED)
finally:
sys.setswitchinterval(oldswitchinterval)
class ProcessPoolWaitTests(ProcessPoolMixin, WaitTests, BaseTestCase):
pass
class AsCompletedTests:
# TODO(brian@sweetapp.com): Should have a test with a non-zero timeout.
def test_no_timeout(self):
future1 = self.executor.submit(mul, 2, 21)
future2 = self.executor.submit(mul, 7, 6)
completed = set(futures.as_completed(
[CANCELLED_AND_NOTIFIED_FUTURE,
EXCEPTION_FUTURE,
SUCCESSFUL_FUTURE,
future1, future2]))
self.assertEqual(set(
[CANCELLED_AND_NOTIFIED_FUTURE,
EXCEPTION_FUTURE,
SUCCESSFUL_FUTURE,
future1, future2]),
completed)
def test_zero_timeout(self):
future1 = self.executor.submit(time.sleep, 2)
completed_futures = set()
try:
for future in futures.as_completed(
[CANCELLED_AND_NOTIFIED_FUTURE,
EXCEPTION_FUTURE,
SUCCESSFUL_FUTURE,
future1],
timeout=0):
completed_futures.add(future)
except futures.TimeoutError:
pass
self.assertEqual(set([CANCELLED_AND_NOTIFIED_FUTURE,
EXCEPTION_FUTURE,
SUCCESSFUL_FUTURE]),
completed_futures)
def test_duplicate_futures(self):
# Issue 20367. Duplicate futures should not raise exceptions or give
# duplicate responses.
# Issue #31641: accept arbitrary iterables.
future1 = self.executor.submit(time.sleep, 2)
completed = [
f for f in futures.as_completed(itertools.repeat(future1, 3))
]
self.assertEqual(len(completed), 1)
def test_free_reference_yielded_future(self):
# Issue #14406: Generator should not keep references
# to finished futures.
futures_list = [Future() for _ in range(8)]
futures_list.append(create_future(state=CANCELLED_AND_NOTIFIED))
futures_list.append(create_future(state=FINISHED, result=42))
with self.assertRaises(futures.TimeoutError):
for future in futures.as_completed(futures_list, timeout=0):
futures_list.remove(future)
wr = weakref.ref(future)
del future
self.assertIsNone(wr())
futures_list[0].set_result("test")
for future in futures.as_completed(futures_list):
futures_list.remove(future)
wr = weakref.ref(future)
del future
self.assertIsNone(wr())
if futures_list:
futures_list[0].set_result("test")
def test_correct_timeout_exception_msg(self):
futures_list = [CANCELLED_AND_NOTIFIED_FUTURE, PENDING_FUTURE,
RUNNING_FUTURE, SUCCESSFUL_FUTURE]
with self.assertRaises(futures.TimeoutError) as cm:
list(futures.as_completed(futures_list, timeout=0))
self.assertEqual(str(cm.exception), '2 (of 4) futures unfinished')
class ThreadPoolAsCompletedTests(ThreadPoolMixin, AsCompletedTests, BaseTestCase):
pass
class ProcessPoolAsCompletedTests(ProcessPoolMixin, AsCompletedTests, BaseTestCase):
pass
class ExecutorTest:
# Executor.shutdown() and context manager usage is tested by
# ExecutorShutdownTest.
def test_submit(self):
future = self.executor.submit(pow, 2, 8)
self.assertEqual(256, future.result())
def test_submit_keyword(self):
future = self.executor.submit(mul, 2, y=8)
self.assertEqual(16, future.result())
def test_map(self):
self.assertEqual(
list(self.executor.map(pow, range(10), range(10))),
list(map(pow, range(10), range(10))))
self.assertEqual(
list(self.executor.map(pow, range(10), range(10), chunksize=3)),
list(map(pow, range(10), range(10))))
def test_map_exception(self):
i = self.executor.map(divmod, [1, 1, 1, 1], [2, 3, 0, 5])
self.assertEqual(i.__next__(), (0, 1))
self.assertEqual(i.__next__(), (0, 1))
self.assertRaises(ZeroDivisionError, i.__next__)
def test_map_timeout(self):
results = []
try:
for i in self.executor.map(time.sleep,
[0, 0, 6],
timeout=5):
results.append(i)
except futures.TimeoutError:
pass
else:
self.fail('expected TimeoutError')
self.assertEqual([None, None], results)
def test_shutdown_race_issue12456(self):
# Issue #12456: race condition at shutdown where trying to post a
# sentinel in the call queue blocks (the queue is full while processes
# have exited).
self.executor.map(str, [2] * (self.worker_count + 1))
self.executor.shutdown()
@test.support.cpython_only
def test_no_stale_references(self):
# Issue #16284: check that the executors don't unnecessarily hang onto
# references.
my_object = MyObject()
my_object_collected = threading.Event()
my_object_callback = weakref.ref(
my_object, lambda obj: my_object_collected.set())
# Deliberately discarding the future.
self.executor.submit(my_object.my_method)
del my_object
collected = my_object_collected.wait(timeout=5.0)
self.assertTrue(collected,
"Stale reference not collected within timeout.")
def test_max_workers_negative(self):
for number in (0, -1):
with self.assertRaisesRegex(ValueError,
"max_workers must be greater "
"than 0"):
self.executor_type(max_workers=number)
def test_free_reference(self):
# Issue #14406: Result iterator should not keep an internal
# reference to result objects.
for obj in self.executor.map(make_dummy_object, range(10)):
wr = weakref.ref(obj)
del obj
self.assertIsNone(wr())
class ThreadPoolExecutorTest(ThreadPoolMixin, ExecutorTest, BaseTestCase):
def test_map_submits_without_iteration(self):
"""Tests verifying issue 11777."""
finished = []
def record_finished(n):
finished.append(n)
self.executor.map(record_finished, range(10))
self.executor.shutdown(wait=True)
self.assertCountEqual(finished, range(10))
def test_default_workers(self):
executor = self.executor_type()
self.assertEqual(executor._max_workers,
(os.cpu_count() or 1) * 5)
class ProcessPoolExecutorTest(ProcessPoolMixin, ExecutorTest, BaseTestCase):
def test_killed_child(self):
# When a child process is abruptly terminated, the whole pool gets
# "broken".
futures = [self.executor.submit(time.sleep, 3)]
# Get one of the processes, and terminate (kill) it
p = next(iter(self.executor._processes.values()))
p.terminate()
for fut in futures:
self.assertRaises(BrokenProcessPool, fut.result)
# Submitting other jobs fails as well.
self.assertRaises(BrokenProcessPool, self.executor.submit, pow, 2, 8)
def test_map_chunksize(self):
def bad_map():
list(self.executor.map(pow, range(40), range(40), chunksize=-1))
ref = list(map(pow, range(40), range(40)))
self.assertEqual(
list(self.executor.map(pow, range(40), range(40), chunksize=6)),
ref)
self.assertEqual(
list(self.executor.map(pow, range(40), range(40), chunksize=50)),
ref)
self.assertEqual(
list(self.executor.map(pow, range(40), range(40), chunksize=40)),
ref)
self.assertRaises(ValueError, bad_map)
@classmethod
def _test_traceback(cls):
raise RuntimeError(123) # some comment
def test_traceback(self):
# We want ensure that the traceback from the child process is
# contained in the traceback raised in the main process.
future = self.executor.submit(self._test_traceback)
with self.assertRaises(Exception) as cm:
future.result()
exc = cm.exception
self.assertIs(type(exc), RuntimeError)
self.assertEqual(exc.args, (123,))
cause = exc.__cause__
self.assertIs(type(cause), futures.process._RemoteTraceback)
self.assertIn('raise RuntimeError(123) # some comment', cause.tb)
with test.support.captured_stderr() as f1:
try:
raise exc
except RuntimeError:
sys.excepthook(*sys.exc_info())
self.assertIn('raise RuntimeError(123) # some comment',
f1.getvalue())
class FutureTests(BaseTestCase):
def test_done_callback_with_result(self):
callback_result = None
def fn(callback_future):
nonlocal callback_result
callback_result = callback_future.result()
f = Future()
f.add_done_callback(fn)
f.set_result(5)
self.assertEqual(5, callback_result)
def test_done_callback_with_exception(self):
callback_exception = None
def fn(callback_future):
nonlocal callback_exception
callback_exception = callback_future.exception()
f = Future()
f.add_done_callback(fn)
f.set_exception(Exception('test'))
self.assertEqual(('test',), callback_exception.args)
def test_done_callback_with_cancel(self):
was_cancelled = None
def fn(callback_future):
nonlocal was_cancelled
was_cancelled = callback_future.cancelled()
f = Future()
f.add_done_callback(fn)
self.assertTrue(f.cancel())
self.assertTrue(was_cancelled)
def test_done_callback_raises(self):
with test.support.captured_stderr() as stderr:
raising_was_called = False
fn_was_called = False
def raising_fn(callback_future):
nonlocal raising_was_called
raising_was_called = True
raise Exception('doh!')
def fn(callback_future):
nonlocal fn_was_called
fn_was_called = True
f = Future()
f.add_done_callback(raising_fn)
f.add_done_callback(fn)
f.set_result(5)
self.assertTrue(raising_was_called)
self.assertTrue(fn_was_called)
self.assertIn('Exception: doh!', stderr.getvalue())
def test_done_callback_already_successful(self):
callback_result = None
def fn(callback_future):
nonlocal callback_result
callback_result = callback_future.result()
f = Future()
f.set_result(5)
f.add_done_callback(fn)
self.assertEqual(5, callback_result)
def test_done_callback_already_failed(self):
callback_exception = None
def fn(callback_future):
nonlocal callback_exception
callback_exception = callback_future.exception()
f = Future()
f.set_exception(Exception('test'))
f.add_done_callback(fn)
self.assertEqual(('test',), callback_exception.args)
def test_done_callback_already_cancelled(self):
was_cancelled = None
def fn(callback_future):
nonlocal was_cancelled
was_cancelled = callback_future.cancelled()
f = Future()
self.assertTrue(f.cancel())
f.add_done_callback(fn)
self.assertTrue(was_cancelled)
def test_repr(self):
self.assertRegex(repr(PENDING_FUTURE),
'<Future at 0x[0-9a-f]+ state=pending>')
self.assertRegex(repr(RUNNING_FUTURE),
'<Future at 0x[0-9a-f]+ state=running>')
self.assertRegex(repr(CANCELLED_FUTURE),
'<Future at 0x[0-9a-f]+ state=cancelled>')
self.assertRegex(repr(CANCELLED_AND_NOTIFIED_FUTURE),
'<Future at 0x[0-9a-f]+ state=cancelled>')
self.assertRegex(
repr(EXCEPTION_FUTURE),
'<Future at 0x[0-9a-f]+ state=finished raised OSError>')
self.assertRegex(
repr(SUCCESSFUL_FUTURE),
'<Future at 0x[0-9a-f]+ state=finished returned int>')
def test_cancel(self):
f1 = create_future(state=PENDING)
f2 = create_future(state=RUNNING)
f3 = create_future(state=CANCELLED)
f4 = create_future(state=CANCELLED_AND_NOTIFIED)
f5 = create_future(state=FINISHED, exception=OSError())
f6 = create_future(state=FINISHED, result=5)
self.assertTrue(f1.cancel())
self.assertEqual(f1._state, CANCELLED)
self.assertFalse(f2.cancel())
self.assertEqual(f2._state, RUNNING)
self.assertTrue(f3.cancel())
self.assertEqual(f3._state, CANCELLED)
self.assertTrue(f4.cancel())
self.assertEqual(f4._state, CANCELLED_AND_NOTIFIED)
self.assertFalse(f5.cancel())
self.assertEqual(f5._state, FINISHED)
self.assertFalse(f6.cancel())
self.assertEqual(f6._state, FINISHED)
def test_cancelled(self):
self.assertFalse(PENDING_FUTURE.cancelled())
self.assertFalse(RUNNING_FUTURE.cancelled())
self.assertTrue(CANCELLED_FUTURE.cancelled())
self.assertTrue(CANCELLED_AND_NOTIFIED_FUTURE.cancelled())
self.assertFalse(EXCEPTION_FUTURE.cancelled())
self.assertFalse(SUCCESSFUL_FUTURE.cancelled())
def test_done(self):
self.assertFalse(PENDING_FUTURE.done())
self.assertFalse(RUNNING_FUTURE.done())
self.assertTrue(CANCELLED_FUTURE.done())
self.assertTrue(CANCELLED_AND_NOTIFIED_FUTURE.done())
self.assertTrue(EXCEPTION_FUTURE.done())
self.assertTrue(SUCCESSFUL_FUTURE.done())
def test_running(self):
self.assertFalse(PENDING_FUTURE.running())
self.assertTrue(RUNNING_FUTURE.running())
self.assertFalse(CANCELLED_FUTURE.running())
self.assertFalse(CANCELLED_AND_NOTIFIED_FUTURE.running())
self.assertFalse(EXCEPTION_FUTURE.running())
self.assertFalse(SUCCESSFUL_FUTURE.running())
def test_result_with_timeout(self):
self.assertRaises(futures.TimeoutError,
PENDING_FUTURE.result, timeout=0)
self.assertRaises(futures.TimeoutError,
RUNNING_FUTURE.result, timeout=0)
self.assertRaises(futures.CancelledError,
CANCELLED_FUTURE.result, timeout=0)
self.assertRaises(futures.CancelledError,
CANCELLED_AND_NOTIFIED_FUTURE.result, timeout=0)
self.assertRaises(OSError, EXCEPTION_FUTURE.result, timeout=0)
self.assertEqual(SUCCESSFUL_FUTURE.result(timeout=0), 42)
def test_result_with_success(self):
# TODO(brian@sweetapp.com): This test is timing dependent.
def notification():
# Wait until the main thread is waiting for the result.
time.sleep(1)
f1.set_result(42)
f1 = create_future(state=PENDING)
t = threading.Thread(target=notification)
t.start()
self.assertEqual(f1.result(timeout=5), 42)
t.join()
def test_result_with_cancel(self):
# TODO(brian@sweetapp.com): This test is timing dependent.
def notification():
# Wait until the main thread is waiting for the result.
time.sleep(1)
f1.cancel()
f1 = create_future(state=PENDING)
t = threading.Thread(target=notification)
t.start()
self.assertRaises(futures.CancelledError, f1.result, timeout=5)
t.join()
def test_exception_with_timeout(self):
self.assertRaises(futures.TimeoutError,
PENDING_FUTURE.exception, timeout=0)
self.assertRaises(futures.TimeoutError,
RUNNING_FUTURE.exception, timeout=0)
self.assertRaises(futures.CancelledError,
CANCELLED_FUTURE.exception, timeout=0)
self.assertRaises(futures.CancelledError,
CANCELLED_AND_NOTIFIED_FUTURE.exception, timeout=0)
self.assertTrue(isinstance(EXCEPTION_FUTURE.exception(timeout=0),
OSError))
self.assertEqual(SUCCESSFUL_FUTURE.exception(timeout=0), None)
def test_exception_with_success(self):
def notification():
# Wait until the main thread is waiting for the exception.
time.sleep(1)
with f1._condition:
f1._state = FINISHED
f1._exception = OSError()
f1._condition.notify_all()
f1 = create_future(state=PENDING)
t = threading.Thread(target=notification)
t.start()
self.assertTrue(isinstance(f1.exception(timeout=5), OSError))
t.join()
@test.support.reap_threads
def test_main():
try:
test.support.run_unittest(__name__)
finally:
test.support.reap_children()
if __name__ == "__main__":
test_main()