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6d34bbbfc7
test_reset_internal_locks was looking at Event's _cond._lock. This makes it harder to change internals of the Condition object and makes the test fragile. The test was added by Nir Soffer in 6108d30dde21. Patch by Nir Soffer.
915 lines
27 KiB
Python
915 lines
27 KiB
Python
"""
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Various tests for synchronization primitives.
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"""
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import sys
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import time
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from _thread import start_new_thread, TIMEOUT_MAX
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import threading
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import unittest
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from test import support
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def _wait():
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# A crude wait/yield function not relying on synchronization primitives.
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time.sleep(0.01)
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class Bunch(object):
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"""
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A bunch of threads.
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"""
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def __init__(self, f, n, wait_before_exit=False):
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"""
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Construct a bunch of `n` threads running the same function `f`.
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If `wait_before_exit` is True, the threads won't terminate until
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do_finish() is called.
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"""
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self.f = f
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self.n = n
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self.started = []
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self.finished = []
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self._can_exit = not wait_before_exit
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def task():
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tid = threading.get_ident()
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self.started.append(tid)
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try:
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f()
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finally:
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self.finished.append(tid)
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while not self._can_exit:
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_wait()
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try:
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for i in range(n):
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start_new_thread(task, ())
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except:
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self._can_exit = True
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raise
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def wait_for_started(self):
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while len(self.started) < self.n:
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_wait()
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def wait_for_finished(self):
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while len(self.finished) < self.n:
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_wait()
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def do_finish(self):
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self._can_exit = True
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class BaseTestCase(unittest.TestCase):
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def setUp(self):
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self._threads = support.threading_setup()
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def tearDown(self):
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support.threading_cleanup(*self._threads)
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support.reap_children()
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def assertTimeout(self, actual, expected):
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# The waiting and/or time.time() can be imprecise, which
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# is why comparing to the expected value would sometimes fail
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# (especially under Windows).
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self.assertGreaterEqual(actual, expected * 0.6)
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# Test nothing insane happened
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self.assertLess(actual, expected * 10.0)
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class BaseLockTests(BaseTestCase):
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"""
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Tests for both recursive and non-recursive locks.
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"""
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def test_constructor(self):
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lock = self.locktype()
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del lock
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def test_repr(self):
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lock = self.locktype()
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self.assertRegex(repr(lock), "<unlocked .* object (.*)?at .*>")
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del lock
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def test_locked_repr(self):
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lock = self.locktype()
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lock.acquire()
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self.assertRegex(repr(lock), "<locked .* object (.*)?at .*>")
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del lock
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def test_acquire_destroy(self):
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lock = self.locktype()
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lock.acquire()
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del lock
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def test_acquire_release(self):
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lock = self.locktype()
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lock.acquire()
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lock.release()
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del lock
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def test_try_acquire(self):
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lock = self.locktype()
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self.assertTrue(lock.acquire(False))
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lock.release()
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def test_try_acquire_contended(self):
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lock = self.locktype()
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lock.acquire()
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result = []
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def f():
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result.append(lock.acquire(False))
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Bunch(f, 1).wait_for_finished()
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self.assertFalse(result[0])
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lock.release()
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def test_acquire_contended(self):
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lock = self.locktype()
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lock.acquire()
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N = 5
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def f():
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lock.acquire()
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lock.release()
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b = Bunch(f, N)
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b.wait_for_started()
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_wait()
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self.assertEqual(len(b.finished), 0)
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lock.release()
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b.wait_for_finished()
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self.assertEqual(len(b.finished), N)
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def test_with(self):
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lock = self.locktype()
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def f():
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lock.acquire()
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lock.release()
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def _with(err=None):
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with lock:
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if err is not None:
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raise err
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_with()
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# Check the lock is unacquired
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Bunch(f, 1).wait_for_finished()
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self.assertRaises(TypeError, _with, TypeError)
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# Check the lock is unacquired
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Bunch(f, 1).wait_for_finished()
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def test_thread_leak(self):
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# The lock shouldn't leak a Thread instance when used from a foreign
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# (non-threading) thread.
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lock = self.locktype()
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def f():
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lock.acquire()
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lock.release()
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n = len(threading.enumerate())
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# We run many threads in the hope that existing threads ids won't
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# be recycled.
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Bunch(f, 15).wait_for_finished()
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if len(threading.enumerate()) != n:
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# There is a small window during which a Thread instance's
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# target function has finished running, but the Thread is still
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# alive and registered. Avoid spurious failures by waiting a
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# bit more (seen on a buildbot).
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time.sleep(0.4)
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self.assertEqual(n, len(threading.enumerate()))
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def test_timeout(self):
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lock = self.locktype()
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# Can't set timeout if not blocking
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self.assertRaises(ValueError, lock.acquire, 0, 1)
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# Invalid timeout values
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self.assertRaises(ValueError, lock.acquire, timeout=-100)
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self.assertRaises(OverflowError, lock.acquire, timeout=1e100)
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self.assertRaises(OverflowError, lock.acquire, timeout=TIMEOUT_MAX + 1)
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# TIMEOUT_MAX is ok
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lock.acquire(timeout=TIMEOUT_MAX)
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lock.release()
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t1 = time.time()
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self.assertTrue(lock.acquire(timeout=5))
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t2 = time.time()
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# Just a sanity test that it didn't actually wait for the timeout.
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self.assertLess(t2 - t1, 5)
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results = []
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def f():
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t1 = time.time()
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results.append(lock.acquire(timeout=0.5))
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t2 = time.time()
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results.append(t2 - t1)
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Bunch(f, 1).wait_for_finished()
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self.assertFalse(results[0])
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self.assertTimeout(results[1], 0.5)
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class LockTests(BaseLockTests):
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"""
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Tests for non-recursive, weak locks
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(which can be acquired and released from different threads).
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"""
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def test_reacquire(self):
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# Lock needs to be released before re-acquiring.
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lock = self.locktype()
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phase = []
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def f():
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lock.acquire()
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phase.append(None)
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lock.acquire()
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phase.append(None)
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start_new_thread(f, ())
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while len(phase) == 0:
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_wait()
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_wait()
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self.assertEqual(len(phase), 1)
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lock.release()
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while len(phase) == 1:
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_wait()
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self.assertEqual(len(phase), 2)
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def test_different_thread(self):
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# Lock can be released from a different thread.
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lock = self.locktype()
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lock.acquire()
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def f():
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lock.release()
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b = Bunch(f, 1)
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b.wait_for_finished()
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lock.acquire()
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lock.release()
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def test_state_after_timeout(self):
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# Issue #11618: check that lock is in a proper state after a
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# (non-zero) timeout.
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lock = self.locktype()
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lock.acquire()
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self.assertFalse(lock.acquire(timeout=0.01))
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lock.release()
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self.assertFalse(lock.locked())
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self.assertTrue(lock.acquire(blocking=False))
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class RLockTests(BaseLockTests):
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"""
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Tests for recursive locks.
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"""
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def test_reacquire(self):
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lock = self.locktype()
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lock.acquire()
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lock.acquire()
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lock.release()
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lock.acquire()
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lock.release()
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lock.release()
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def test_release_unacquired(self):
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# Cannot release an unacquired lock
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lock = self.locktype()
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self.assertRaises(RuntimeError, lock.release)
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lock.acquire()
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lock.acquire()
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lock.release()
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lock.acquire()
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lock.release()
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lock.release()
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self.assertRaises(RuntimeError, lock.release)
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def test_release_save_unacquired(self):
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# Cannot _release_save an unacquired lock
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lock = self.locktype()
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self.assertRaises(RuntimeError, lock._release_save)
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lock.acquire()
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lock.acquire()
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lock.release()
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lock.acquire()
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lock.release()
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lock.release()
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self.assertRaises(RuntimeError, lock._release_save)
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def test_different_thread(self):
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# Cannot release from a different thread
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lock = self.locktype()
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def f():
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lock.acquire()
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b = Bunch(f, 1, True)
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try:
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self.assertRaises(RuntimeError, lock.release)
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finally:
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b.do_finish()
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def test__is_owned(self):
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lock = self.locktype()
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self.assertFalse(lock._is_owned())
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lock.acquire()
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self.assertTrue(lock._is_owned())
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lock.acquire()
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self.assertTrue(lock._is_owned())
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result = []
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def f():
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result.append(lock._is_owned())
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Bunch(f, 1).wait_for_finished()
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self.assertFalse(result[0])
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lock.release()
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self.assertTrue(lock._is_owned())
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lock.release()
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self.assertFalse(lock._is_owned())
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class EventTests(BaseTestCase):
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"""
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Tests for Event objects.
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"""
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def test_is_set(self):
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evt = self.eventtype()
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self.assertFalse(evt.is_set())
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evt.set()
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self.assertTrue(evt.is_set())
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evt.set()
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self.assertTrue(evt.is_set())
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evt.clear()
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self.assertFalse(evt.is_set())
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evt.clear()
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self.assertFalse(evt.is_set())
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def _check_notify(self, evt):
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# All threads get notified
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N = 5
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results1 = []
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results2 = []
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def f():
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results1.append(evt.wait())
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results2.append(evt.wait())
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b = Bunch(f, N)
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b.wait_for_started()
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_wait()
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self.assertEqual(len(results1), 0)
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evt.set()
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b.wait_for_finished()
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self.assertEqual(results1, [True] * N)
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self.assertEqual(results2, [True] * N)
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def test_notify(self):
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evt = self.eventtype()
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self._check_notify(evt)
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# Another time, after an explicit clear()
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evt.set()
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evt.clear()
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self._check_notify(evt)
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def test_timeout(self):
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evt = self.eventtype()
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results1 = []
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results2 = []
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N = 5
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def f():
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results1.append(evt.wait(0.0))
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t1 = time.time()
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r = evt.wait(0.5)
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t2 = time.time()
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results2.append((r, t2 - t1))
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Bunch(f, N).wait_for_finished()
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self.assertEqual(results1, [False] * N)
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for r, dt in results2:
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self.assertFalse(r)
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self.assertTimeout(dt, 0.5)
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# The event is set
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results1 = []
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results2 = []
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evt.set()
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Bunch(f, N).wait_for_finished()
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self.assertEqual(results1, [True] * N)
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for r, dt in results2:
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self.assertTrue(r)
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def test_set_and_clear(self):
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# Issue #13502: check that wait() returns true even when the event is
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# cleared before the waiting thread is woken up.
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evt = self.eventtype()
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results = []
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N = 5
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def f():
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results.append(evt.wait(1))
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b = Bunch(f, N)
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b.wait_for_started()
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time.sleep(0.5)
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evt.set()
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evt.clear()
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b.wait_for_finished()
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self.assertEqual(results, [True] * N)
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def test_reset_internal_locks(self):
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# ensure that condition is still using a Lock after reset
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evt = self.eventtype()
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with evt._cond:
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self.assertFalse(evt._cond.acquire(False))
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evt._reset_internal_locks()
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with evt._cond:
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self.assertFalse(evt._cond.acquire(False))
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class ConditionTests(BaseTestCase):
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"""
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Tests for condition variables.
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"""
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def test_acquire(self):
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cond = self.condtype()
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# Be default we have an RLock: the condition can be acquired multiple
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# times.
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cond.acquire()
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cond.acquire()
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cond.release()
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cond.release()
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lock = threading.Lock()
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cond = self.condtype(lock)
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cond.acquire()
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self.assertFalse(lock.acquire(False))
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cond.release()
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self.assertTrue(lock.acquire(False))
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self.assertFalse(cond.acquire(False))
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lock.release()
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with cond:
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self.assertFalse(lock.acquire(False))
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def test_unacquired_wait(self):
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cond = self.condtype()
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self.assertRaises(RuntimeError, cond.wait)
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def test_unacquired_notify(self):
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cond = self.condtype()
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self.assertRaises(RuntimeError, cond.notify)
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def _check_notify(self, cond):
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# Note that this test is sensitive to timing. If the worker threads
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# don't execute in a timely fashion, the main thread may think they
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# are further along then they are. The main thread therefore issues
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# _wait() statements to try to make sure that it doesn't race ahead
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# of the workers.
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# Secondly, this test assumes that condition variables are not subject
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# to spurious wakeups. The absence of spurious wakeups is an implementation
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# detail of Condition Cariables in current CPython, but in general, not
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# a guaranteed property of condition variables as a programming
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# construct. In particular, it is possible that this can no longer
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# be conveniently guaranteed should their implementation ever change.
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N = 5
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results1 = []
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results2 = []
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phase_num = 0
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def f():
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cond.acquire()
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result = cond.wait()
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cond.release()
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results1.append((result, phase_num))
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cond.acquire()
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result = cond.wait()
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cond.release()
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results2.append((result, phase_num))
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b = Bunch(f, N)
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b.wait_for_started()
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_wait()
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self.assertEqual(results1, [])
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# Notify 3 threads at first
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cond.acquire()
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cond.notify(3)
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_wait()
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phase_num = 1
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cond.release()
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while len(results1) < 3:
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_wait()
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self.assertEqual(results1, [(True, 1)] * 3)
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self.assertEqual(results2, [])
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# first wait, to ensure all workers settle into cond.wait() before
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# we continue. See issue #8799
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_wait()
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# Notify 5 threads: they might be in their first or second wait
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cond.acquire()
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cond.notify(5)
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_wait()
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phase_num = 2
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cond.release()
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while len(results1) + len(results2) < 8:
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_wait()
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self.assertEqual(results1, [(True, 1)] * 3 + [(True, 2)] * 2)
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self.assertEqual(results2, [(True, 2)] * 3)
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_wait() # make sure all workers settle into cond.wait()
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# Notify all threads: they are all in their second wait
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cond.acquire()
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cond.notify_all()
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_wait()
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phase_num = 3
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cond.release()
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while len(results2) < 5:
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_wait()
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self.assertEqual(results1, [(True, 1)] * 3 + [(True,2)] * 2)
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self.assertEqual(results2, [(True, 2)] * 3 + [(True, 3)] * 2)
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b.wait_for_finished()
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def test_notify(self):
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cond = self.condtype()
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self._check_notify(cond)
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# A second time, to check internal state is still ok.
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self._check_notify(cond)
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def test_timeout(self):
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cond = self.condtype()
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results = []
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N = 5
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def f():
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cond.acquire()
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t1 = time.time()
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result = cond.wait(0.5)
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t2 = time.time()
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cond.release()
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results.append((t2 - t1, result))
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Bunch(f, N).wait_for_finished()
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self.assertEqual(len(results), N)
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for dt, result in results:
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self.assertTimeout(dt, 0.5)
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# Note that conceptually (that"s the condition variable protocol)
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# a wait() may succeed even if no one notifies us and before any
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# timeout occurs. Spurious wakeups can occur.
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# This makes it hard to verify the result value.
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# In practice, this implementation has no spurious wakeups.
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self.assertFalse(result)
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def test_waitfor(self):
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cond = self.condtype()
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state = 0
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def f():
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with cond:
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result = cond.wait_for(lambda : state==4)
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self.assertTrue(result)
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self.assertEqual(state, 4)
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b = Bunch(f, 1)
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b.wait_for_started()
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for i in range(4):
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time.sleep(0.01)
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with cond:
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|
state += 1
|
|
cond.notify()
|
|
b.wait_for_finished()
|
|
|
|
def test_waitfor_timeout(self):
|
|
cond = self.condtype()
|
|
state = 0
|
|
success = []
|
|
def f():
|
|
with cond:
|
|
dt = time.time()
|
|
result = cond.wait_for(lambda : state==4, timeout=0.1)
|
|
dt = time.time() - dt
|
|
self.assertFalse(result)
|
|
self.assertTimeout(dt, 0.1)
|
|
success.append(None)
|
|
b = Bunch(f, 1)
|
|
b.wait_for_started()
|
|
# Only increment 3 times, so state == 4 is never reached.
|
|
for i in range(3):
|
|
time.sleep(0.01)
|
|
with cond:
|
|
state += 1
|
|
cond.notify()
|
|
b.wait_for_finished()
|
|
self.assertEqual(len(success), 1)
|
|
|
|
|
|
class BaseSemaphoreTests(BaseTestCase):
|
|
"""
|
|
Common tests for {bounded, unbounded} semaphore objects.
|
|
"""
|
|
|
|
def test_constructor(self):
|
|
self.assertRaises(ValueError, self.semtype, value = -1)
|
|
self.assertRaises(ValueError, self.semtype, value = -sys.maxsize)
|
|
|
|
def test_acquire(self):
|
|
sem = self.semtype(1)
|
|
sem.acquire()
|
|
sem.release()
|
|
sem = self.semtype(2)
|
|
sem.acquire()
|
|
sem.acquire()
|
|
sem.release()
|
|
sem.release()
|
|
|
|
def test_acquire_destroy(self):
|
|
sem = self.semtype()
|
|
sem.acquire()
|
|
del sem
|
|
|
|
def test_acquire_contended(self):
|
|
sem = self.semtype(7)
|
|
sem.acquire()
|
|
N = 10
|
|
results1 = []
|
|
results2 = []
|
|
phase_num = 0
|
|
def f():
|
|
sem.acquire()
|
|
results1.append(phase_num)
|
|
sem.acquire()
|
|
results2.append(phase_num)
|
|
b = Bunch(f, 10)
|
|
b.wait_for_started()
|
|
while len(results1) + len(results2) < 6:
|
|
_wait()
|
|
self.assertEqual(results1 + results2, [0] * 6)
|
|
phase_num = 1
|
|
for i in range(7):
|
|
sem.release()
|
|
while len(results1) + len(results2) < 13:
|
|
_wait()
|
|
self.assertEqual(sorted(results1 + results2), [0] * 6 + [1] * 7)
|
|
phase_num = 2
|
|
for i in range(6):
|
|
sem.release()
|
|
while len(results1) + len(results2) < 19:
|
|
_wait()
|
|
self.assertEqual(sorted(results1 + results2), [0] * 6 + [1] * 7 + [2] * 6)
|
|
# The semaphore is still locked
|
|
self.assertFalse(sem.acquire(False))
|
|
# Final release, to let the last thread finish
|
|
sem.release()
|
|
b.wait_for_finished()
|
|
|
|
def test_try_acquire(self):
|
|
sem = self.semtype(2)
|
|
self.assertTrue(sem.acquire(False))
|
|
self.assertTrue(sem.acquire(False))
|
|
self.assertFalse(sem.acquire(False))
|
|
sem.release()
|
|
self.assertTrue(sem.acquire(False))
|
|
|
|
def test_try_acquire_contended(self):
|
|
sem = self.semtype(4)
|
|
sem.acquire()
|
|
results = []
|
|
def f():
|
|
results.append(sem.acquire(False))
|
|
results.append(sem.acquire(False))
|
|
Bunch(f, 5).wait_for_finished()
|
|
# There can be a thread switch between acquiring the semaphore and
|
|
# appending the result, therefore results will not necessarily be
|
|
# ordered.
|
|
self.assertEqual(sorted(results), [False] * 7 + [True] * 3 )
|
|
|
|
def test_acquire_timeout(self):
|
|
sem = self.semtype(2)
|
|
self.assertRaises(ValueError, sem.acquire, False, timeout=1.0)
|
|
self.assertTrue(sem.acquire(timeout=0.005))
|
|
self.assertTrue(sem.acquire(timeout=0.005))
|
|
self.assertFalse(sem.acquire(timeout=0.005))
|
|
sem.release()
|
|
self.assertTrue(sem.acquire(timeout=0.005))
|
|
t = time.time()
|
|
self.assertFalse(sem.acquire(timeout=0.5))
|
|
dt = time.time() - t
|
|
self.assertTimeout(dt, 0.5)
|
|
|
|
def test_default_value(self):
|
|
# The default initial value is 1.
|
|
sem = self.semtype()
|
|
sem.acquire()
|
|
def f():
|
|
sem.acquire()
|
|
sem.release()
|
|
b = Bunch(f, 1)
|
|
b.wait_for_started()
|
|
_wait()
|
|
self.assertFalse(b.finished)
|
|
sem.release()
|
|
b.wait_for_finished()
|
|
|
|
def test_with(self):
|
|
sem = self.semtype(2)
|
|
def _with(err=None):
|
|
with sem:
|
|
self.assertTrue(sem.acquire(False))
|
|
sem.release()
|
|
with sem:
|
|
self.assertFalse(sem.acquire(False))
|
|
if err:
|
|
raise err
|
|
_with()
|
|
self.assertTrue(sem.acquire(False))
|
|
sem.release()
|
|
self.assertRaises(TypeError, _with, TypeError)
|
|
self.assertTrue(sem.acquire(False))
|
|
sem.release()
|
|
|
|
class SemaphoreTests(BaseSemaphoreTests):
|
|
"""
|
|
Tests for unbounded semaphores.
|
|
"""
|
|
|
|
def test_release_unacquired(self):
|
|
# Unbounded releases are allowed and increment the semaphore's value
|
|
sem = self.semtype(1)
|
|
sem.release()
|
|
sem.acquire()
|
|
sem.acquire()
|
|
sem.release()
|
|
|
|
|
|
class BoundedSemaphoreTests(BaseSemaphoreTests):
|
|
"""
|
|
Tests for bounded semaphores.
|
|
"""
|
|
|
|
def test_release_unacquired(self):
|
|
# Cannot go past the initial value
|
|
sem = self.semtype()
|
|
self.assertRaises(ValueError, sem.release)
|
|
sem.acquire()
|
|
sem.release()
|
|
self.assertRaises(ValueError, sem.release)
|
|
|
|
|
|
class BarrierTests(BaseTestCase):
|
|
"""
|
|
Tests for Barrier objects.
|
|
"""
|
|
N = 5
|
|
defaultTimeout = 2.0
|
|
|
|
def setUp(self):
|
|
self.barrier = self.barriertype(self.N, timeout=self.defaultTimeout)
|
|
def tearDown(self):
|
|
self.barrier.abort()
|
|
|
|
def run_threads(self, f):
|
|
b = Bunch(f, self.N-1)
|
|
f()
|
|
b.wait_for_finished()
|
|
|
|
def multipass(self, results, n):
|
|
m = self.barrier.parties
|
|
self.assertEqual(m, self.N)
|
|
for i in range(n):
|
|
results[0].append(True)
|
|
self.assertEqual(len(results[1]), i * m)
|
|
self.barrier.wait()
|
|
results[1].append(True)
|
|
self.assertEqual(len(results[0]), (i + 1) * m)
|
|
self.barrier.wait()
|
|
self.assertEqual(self.barrier.n_waiting, 0)
|
|
self.assertFalse(self.barrier.broken)
|
|
|
|
def test_barrier(self, passes=1):
|
|
"""
|
|
Test that a barrier is passed in lockstep
|
|
"""
|
|
results = [[],[]]
|
|
def f():
|
|
self.multipass(results, passes)
|
|
self.run_threads(f)
|
|
|
|
def test_barrier_10(self):
|
|
"""
|
|
Test that a barrier works for 10 consecutive runs
|
|
"""
|
|
return self.test_barrier(10)
|
|
|
|
def test_wait_return(self):
|
|
"""
|
|
test the return value from barrier.wait
|
|
"""
|
|
results = []
|
|
def f():
|
|
r = self.barrier.wait()
|
|
results.append(r)
|
|
|
|
self.run_threads(f)
|
|
self.assertEqual(sum(results), sum(range(self.N)))
|
|
|
|
def test_action(self):
|
|
"""
|
|
Test the 'action' callback
|
|
"""
|
|
results = []
|
|
def action():
|
|
results.append(True)
|
|
barrier = self.barriertype(self.N, action)
|
|
def f():
|
|
barrier.wait()
|
|
self.assertEqual(len(results), 1)
|
|
|
|
self.run_threads(f)
|
|
|
|
def test_abort(self):
|
|
"""
|
|
Test that an abort will put the barrier in a broken state
|
|
"""
|
|
results1 = []
|
|
results2 = []
|
|
def f():
|
|
try:
|
|
i = self.barrier.wait()
|
|
if i == self.N//2:
|
|
raise RuntimeError
|
|
self.barrier.wait()
|
|
results1.append(True)
|
|
except threading.BrokenBarrierError:
|
|
results2.append(True)
|
|
except RuntimeError:
|
|
self.barrier.abort()
|
|
pass
|
|
|
|
self.run_threads(f)
|
|
self.assertEqual(len(results1), 0)
|
|
self.assertEqual(len(results2), self.N-1)
|
|
self.assertTrue(self.barrier.broken)
|
|
|
|
def test_reset(self):
|
|
"""
|
|
Test that a 'reset' on a barrier frees the waiting threads
|
|
"""
|
|
results1 = []
|
|
results2 = []
|
|
results3 = []
|
|
def f():
|
|
i = self.barrier.wait()
|
|
if i == self.N//2:
|
|
# Wait until the other threads are all in the barrier.
|
|
while self.barrier.n_waiting < self.N-1:
|
|
time.sleep(0.001)
|
|
self.barrier.reset()
|
|
else:
|
|
try:
|
|
self.barrier.wait()
|
|
results1.append(True)
|
|
except threading.BrokenBarrierError:
|
|
results2.append(True)
|
|
# Now, pass the barrier again
|
|
self.barrier.wait()
|
|
results3.append(True)
|
|
|
|
self.run_threads(f)
|
|
self.assertEqual(len(results1), 0)
|
|
self.assertEqual(len(results2), self.N-1)
|
|
self.assertEqual(len(results3), self.N)
|
|
|
|
|
|
def test_abort_and_reset(self):
|
|
"""
|
|
Test that a barrier can be reset after being broken.
|
|
"""
|
|
results1 = []
|
|
results2 = []
|
|
results3 = []
|
|
barrier2 = self.barriertype(self.N)
|
|
def f():
|
|
try:
|
|
i = self.barrier.wait()
|
|
if i == self.N//2:
|
|
raise RuntimeError
|
|
self.barrier.wait()
|
|
results1.append(True)
|
|
except threading.BrokenBarrierError:
|
|
results2.append(True)
|
|
except RuntimeError:
|
|
self.barrier.abort()
|
|
pass
|
|
# Synchronize and reset the barrier. Must synchronize first so
|
|
# that everyone has left it when we reset, and after so that no
|
|
# one enters it before the reset.
|
|
if barrier2.wait() == self.N//2:
|
|
self.barrier.reset()
|
|
barrier2.wait()
|
|
self.barrier.wait()
|
|
results3.append(True)
|
|
|
|
self.run_threads(f)
|
|
self.assertEqual(len(results1), 0)
|
|
self.assertEqual(len(results2), self.N-1)
|
|
self.assertEqual(len(results3), self.N)
|
|
|
|
def test_timeout(self):
|
|
"""
|
|
Test wait(timeout)
|
|
"""
|
|
def f():
|
|
i = self.barrier.wait()
|
|
if i == self.N // 2:
|
|
# One thread is late!
|
|
time.sleep(1.0)
|
|
# Default timeout is 2.0, so this is shorter.
|
|
self.assertRaises(threading.BrokenBarrierError,
|
|
self.barrier.wait, 0.5)
|
|
self.run_threads(f)
|
|
|
|
def test_default_timeout(self):
|
|
"""
|
|
Test the barrier's default timeout
|
|
"""
|
|
# create a barrier with a low default timeout
|
|
barrier = self.barriertype(self.N, timeout=0.3)
|
|
def f():
|
|
i = barrier.wait()
|
|
if i == self.N // 2:
|
|
# One thread is later than the default timeout of 0.3s.
|
|
time.sleep(1.0)
|
|
self.assertRaises(threading.BrokenBarrierError, barrier.wait)
|
|
self.run_threads(f)
|
|
|
|
def test_single_thread(self):
|
|
b = self.barriertype(1)
|
|
b.wait()
|
|
b.wait()
|