Repository navigation
Expand file tree
/
Copy pathtest_concurrent_futures.py
More file actions
1258 lines (1017 loc) · 43.1 KB
/
Copy pathtest_concurrent_futures.py
File metadata and controls
1258 lines (1017 loc) · 43.1 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
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')
from test.support.script_helper import assert_python_ok
import contextlib
import itertools
import logging
from logging.handlers import QueueHandler
import os
import queue
import sys
import threading
import time
import unittest
import weakref
from pickle import PicklingError
from concurrent import futures
from concurrent.futures._base import (
PENDING, RUNNING, CANCELLED, CANCELLED_AND_NOTIFIED, FINISHED, Future,
BrokenExecutor)
from concurrent.futures.process import BrokenProcessPool
from multiprocessing import get_context
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)
INITIALIZER_STATUS = 'uninitialized'
def mul(x, y):
return x * y
def capture(*args, **kwargs):
return args, kwargs
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()
def init(x):
global INITIALIZER_STATUS
INITIALIZER_STATUS = x
def get_init_status():
return INITIALIZER_STATUS
def init_fail(log_queue=None):
if log_queue is not None:
logger = logging.getLogger('concurrent.futures')
logger.addHandler(QueueHandler(log_queue))
logger.setLevel('CRITICAL')
logger.propagate = False
time.sleep(0.1) # let some futures be scheduled
raise ValueError('error in initializer')
class MyObject(object):
def my_method(self):
pass
class EventfulGCObj():
def __init__(self, mgr):
self.event = mgr.Event()
def __del__(self):
self.event.set()
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
executor_kwargs = {}
def setUp(self):
super().setUp()
self.t1 = time.monotonic()
if hasattr(self, "ctx"):
self.executor = self.executor_type(
max_workers=self.worker_count,
mp_context=self.get_context(),
**self.executor_kwargs)
else:
self.executor = self.executor_type(
max_workers=self.worker_count,
**self.executor_kwargs)
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 get_context(self):
return get_context(self.ctx)
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 ProcessPoolForkMixin(ExecutorMixin):
executor_type = futures.ProcessPoolExecutor
ctx = "fork"
def get_context(self):
if sys.platform == "win32":
self.skipTest("require unix system")
return super().get_context()
class ProcessPoolSpawnMixin(ExecutorMixin):
executor_type = futures.ProcessPoolExecutor
ctx = "spawn"
class ProcessPoolForkserverMixin(ExecutorMixin):
executor_type = futures.ProcessPoolExecutor
ctx = "forkserver"
def get_context(self):
if sys.platform == "win32":
self.skipTest("require unix system")
return super().get_context()
def create_executor_tests(mixin, bases=(BaseTestCase,),
executor_mixins=(ThreadPoolMixin,
ProcessPoolForkMixin,
ProcessPoolForkserverMixin,
ProcessPoolSpawnMixin)):
def strip_mixin(name):
if name.endswith(('Mixin', 'Tests')):
return name[:-5]
elif name.endswith('Test'):
return name[:-4]
else:
return name
for exe in executor_mixins:
name = ("%s%sTest"
% (strip_mixin(exe.__name__), strip_mixin(mixin.__name__)))
cls = type(name, (mixin,) + (exe,) + bases, {})
globals()[name] = cls
class InitializerMixin(ExecutorMixin):
worker_count = 2
def setUp(self):
global INITIALIZER_STATUS
INITIALIZER_STATUS = 'uninitialized'
self.executor_kwargs = dict(initializer=init,
initargs=('initialized',))
super().setUp()
def test_initializer(self):
futures = [self.executor.submit(get_init_status)
for _ in range(self.worker_count)]
for f in futures:
self.assertEqual(f.result(), 'initialized')
class FailingInitializerMixin(ExecutorMixin):
worker_count = 2
def setUp(self):
if hasattr(self, "ctx"):
# Pass a queue to redirect the child's logging output
self.mp_context = self.get_context()
self.log_queue = self.mp_context.Queue()
self.executor_kwargs = dict(initializer=init_fail,
initargs=(self.log_queue,))
else:
# In a thread pool, the child shares our logging setup
# (see _assert_logged())
self.mp_context = None
self.log_queue = None
self.executor_kwargs = dict(initializer=init_fail)
super().setUp()
def test_initializer(self):
with self._assert_logged('ValueError: error in initializer'):
try:
future = self.executor.submit(get_init_status)
except BrokenExecutor:
# Perhaps the executor is already broken
pass
else:
with self.assertRaises(BrokenExecutor):
future.result()
# At some point, the executor should break
t1 = time.monotonic()
while not self.executor._broken:
if time.monotonic() - t1 > 5:
self.fail("executor not broken after 5 s.")
time.sleep(0.01)
# ... and from this point submit() is guaranteed to fail
with self.assertRaises(BrokenExecutor):
self.executor.submit(get_init_status)
def _prime_executor(self):
pass
@contextlib.contextmanager
def _assert_logged(self, msg):
if self.log_queue is not None:
yield
output = []
try:
while True:
output.append(self.log_queue.get_nowait().getMessage())
except queue.Empty:
pass
else:
with self.assertLogs('concurrent.futures', 'CRITICAL') as cm:
yield
output = cm.output
self.assertTrue(any(msg in line for line in output),
output)
create_executor_tests(InitializerMixin)
create_executor_tests(FailingInitializerMixin)
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
if __name__ == "__main__":
context = '{context}'
if context == "":
t = {executor_type}(5)
else:
from multiprocessing import get_context
context = get_context(context)
t = {executor_type}(5, mp_context=context)
t.submit(sleep_and_print, 1.0, "apple")
""".format(executor_type=self.executor_type.__name__,
context=getattr(self, "ctx", "")))
# 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_submit_after_interpreter_shutdown(self):
# Test the atexit hook for shutdown of worker threads and processes
rc, out, err = assert_python_ok('-c', """if 1:
import atexit
@atexit.register
def run_last():
try:
t.submit(id, None)
except RuntimeError:
print("runtime-error")
raise
from concurrent.futures import {executor_type}
if __name__ == "__main__":
context = '{context}'
if not context:
t = {executor_type}(5)
else:
from multiprocessing import get_context
context = get_context(context)
t = {executor_type}(5, mp_context=context)
t.submit(id, 42).result()
""".format(executor_type=self.executor_type.__name__,
context=getattr(self, "ctx", "")))
# Errors in atexit hooks don't change the process exit code, check
# stderr manually.
self.assertIn("RuntimeError: cannot schedule new futures", err.decode())
self.assertEqual(out.strip(), b"runtime-error")
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(ExecutorShutdownTest):
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
queue_management_thread = executor._queue_management_thread
del executor
# Make sure that all the executor resources were properly cleaned by
# the shutdown process
queue_management_thread.join()
for p in processes.values():
p.join()
call_queue.join_thread()
create_executor_tests(ProcessPoolShutdownTest,
executor_mixins=(ProcessPoolForkMixin,
ProcessPoolForkserverMixin,
ProcessPoolSpawnMixin))
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)
create_executor_tests(WaitTests,
executor_mixins=(ProcessPoolForkMixin,
ProcessPoolForkserverMixin,
ProcessPoolSpawnMixin))
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')
create_executor_tests(AsCompletedTests)
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())
future = self.executor.submit(capture, 1, self=2, fn=3)
self.assertEqual(future.result(), ((1,), {'self': 2, 'fn': 3}))
future = self.executor.submit(fn=capture, arg=1)
self.assertEqual(future.result(), ((), {'arg': 1}))
with self.assertRaises(TypeError):
self.executor.submit(arg=1)
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(ExecutorTest):
@unittest.skipUnless(sys.platform=='win32', 'Windows-only process limit')
def test_max_workers_too_large(self):
with self.assertRaisesRegex(ValueError,
"max_workers must be <= 61"):
futures.ProcessPoolExecutor(max_workers=62)
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())
def test_ressources_gced_in_workers(self):
# Ensure that argument for a job are correctly gc-ed after the job
# is finished
mgr = get_context(self.ctx).Manager()
obj = EventfulGCObj(mgr)
future = self.executor.submit(id, obj)
future.result()
self.assertTrue(obj.event.wait(timeout=1))
# explicitly destroy the object to ensure that EventfulGCObj.__del__()
# is called while manager is still running.
obj = None
support.gc_collect()
mgr.shutdown()
mgr.join()
create_executor_tests(ProcessPoolExecutorTest,
executor_mixins=(ProcessPoolForkMixin,
ProcessPoolForkserverMixin,
ProcessPoolSpawnMixin))
def hide_process_stderr():
import io
sys.stderr = io.StringIO()
def _crash(delay=None):
"""Induces a segfault."""
if delay:
time.sleep(delay)
import faulthandler
faulthandler.disable()
faulthandler._sigsegv()
def _exit():
"""Induces a sys exit with exitcode 1."""
sys.exit(1)
def _raise_error(Err):
"""Function that raises an Exception in process."""
hide_process_stderr()
raise Err()
def _return_instance(cls):
"""Function that returns a instance of cls."""
hide_process_stderr()
return cls()
class CrashAtPickle(object):
"""Bad object that triggers a segfault at pickling time."""
def __reduce__(self):
_crash()
class CrashAtUnpickle(object):
"""Bad object that triggers a segfault at unpickling time."""
def __reduce__(self):
return _crash, ()
class ExitAtPickle(object):
"""Bad object that triggers a process exit at pickling time."""
def __reduce__(self):
_exit()
class ExitAtUnpickle(object):
"""Bad object that triggers a process exit at unpickling time."""
def __reduce__(self):
return _exit, ()
class ErrorAtPickle(object):
"""Bad object that triggers an error at pickling time."""
def __reduce__(self):
from pickle import PicklingError
raise PicklingError("Error in pickle")
class ErrorAtUnpickle(object):
"""Bad object that triggers an error at unpickling time."""
def __reduce__(self):
from pickle import UnpicklingError
return _raise_error, (UnpicklingError, )
class ExecutorDeadlockTest:
TIMEOUT = 15
@classmethod
def _sleep_id(cls, x, delay):
time.sleep(delay)
return x
def _fail_on_deadlock(self, executor):
# If we did not recover before TIMEOUT seconds, consider that the
# executor is in a deadlock state and forcefully clean all its
# composants.
import faulthandler
from tempfile import TemporaryFile
with TemporaryFile(mode="w+") as f:
faulthandler.dump_traceback(file=f)
f.seek(0)
tb = f.read()
for p in executor._processes.values():
p.terminate()
# This should be safe to call executor.shutdown here as all possible
# deadlocks should have been broken.
executor.shutdown(wait=True)
print(f"\nTraceback:\n {tb}", file=sys.__stderr__)
self.fail(f"Executor deadlock:\n\n{tb}")
def test_crash(self):
# extensive testing for deadlock caused by crashes in a pool.
self.executor.shutdown(wait=True)
crash_cases = [
# Check problem occurring while pickling a task in
# the task_handler thread
(id, (ErrorAtPickle(),), PicklingError, "error at task pickle"),
# Check problem occurring while unpickling a task on workers
(id, (ExitAtUnpickle(),), BrokenProcessPool,
"exit at task unpickle"),
(id, (ErrorAtUnpickle(),), BrokenProcessPool,
"error at task unpickle"),
(id, (CrashAtUnpickle(),), BrokenProcessPool,
"crash at task unpickle"),
# Check problem occurring during func execution on workers
(_crash, (), BrokenProcessPool,
"crash during func execution on worker"),
(_exit, (), SystemExit,
"exit during func execution on worker"),
(_raise_error, (RuntimeError, ), RuntimeError,
"error during func execution on worker"),
# Check problem occurring while pickling a task result
# on workers
(_return_instance, (CrashAtPickle,), BrokenProcessPool,
"crash during result pickle on worker"),
(_return_instance, (ExitAtPickle,), SystemExit,
"exit during result pickle on worker"),
(_return_instance, (ErrorAtPickle,), PicklingError,
"error during result pickle on worker"),
# Check problem occurring while unpickling a task in
# the result_handler thread
(_return_instance, (ErrorAtUnpickle,), BrokenProcessPool,
"error during result unpickle in result_handler"),
(_return_instance, (ExitAtUnpickle,), BrokenProcessPool,
"exit during result unpickle in result_handler")
]
for func, args, error, name in crash_cases:
with self.subTest(name):
# The captured_stderr reduces the noise in the test report
with test.support.captured_stderr():
executor = self.executor_type(
max_workers=2, mp_context=get_context(self.ctx))
res = executor.submit(func, *args)
with self.assertRaises(error):
try:
res.result(timeout=self.TIMEOUT)
except futures.TimeoutError:
# If we did not recover before TIMEOUT seconds,
# consider that the executor is in a deadlock state
self._fail_on_deadlock(executor)
executor.shutdown(wait=True)
def test_shutdown_deadlock(self):
# Test that the pool calling shutdown do not cause deadlock
# if a worker fails after the shutdown call.
self.executor.shutdown(wait=True)
with self.executor_type(max_workers=2,
mp_context=get_context(self.ctx)) as executor:
self.executor = executor # Allow clean up in fail_on_deadlock
f = executor.submit(_crash, delay=.1)
executor.shutdown(wait=True)
with self.assertRaises(BrokenProcessPool):
f.result()