test_threadsignals.py 文件源码

def test_lock_acquire_interruption(self):
        # Mimic receiving a SIGINT (KeyboardInterrupt) with SIGALRM while stuck
        # in a deadlock.
        # XXX this test can fail when the legacy (non-semaphore) implementation
        # of locks is used in thread_pthread.h, see issue #11223.
        oldalrm = signal.signal(signal.SIGALRM, self.alarm_interrupt)
        try:
            lock = thread.allocate_lock()
            lock.acquire()
            signal.alarm(1)
            t1 = time.time()
            self.assertRaises(KeyboardInterrupt, lock.acquire, timeout=5)
            dt = time.time() - t1
            # Checking that KeyboardInterrupt was raised is not sufficient.
            # We want to assert that lock.acquire() was interrupted because
            # of the signal, not that the signal handler was called immediately
            # after timeout return of lock.acquire() (which can fool assertRaises).
            self.assertLess(dt, 3.0)
        finally:
            signal.signal(signal.SIGALRM, oldalrm)