| # Some simple queue module tests, plus some failure conditions |
| # to ensure the Queue locks remain stable. |
| import queue |
| import time |
| import unittest |
| from test import support |
| threading = support.import_module('threading') |
| |
| QUEUE_SIZE = 5 |
| |
| def qfull(q): |
| return q.maxsize > 0 and q.qsize() == q.maxsize |
| |
| # A thread to run a function that unclogs a blocked Queue. |
| class _TriggerThread(threading.Thread): |
| def __init__(self, fn, args): |
| self.fn = fn |
| self.args = args |
| self.startedEvent = threading.Event() |
| threading.Thread.__init__(self) |
| |
| def run(self): |
| # The sleep isn't necessary, but is intended to give the blocking |
| # function in the main thread a chance at actually blocking before |
| # we unclog it. But if the sleep is longer than the timeout-based |
| # tests wait in their blocking functions, those tests will fail. |
| # So we give them much longer timeout values compared to the |
| # sleep here (I aimed at 10 seconds for blocking functions -- |
| # they should never actually wait that long - they should make |
| # progress as soon as we call self.fn()). |
| time.sleep(0.1) |
| self.startedEvent.set() |
| self.fn(*self.args) |
| |
| |
| # Execute a function that blocks, and in a separate thread, a function that |
| # triggers the release. Returns the result of the blocking function. Caution: |
| # block_func must guarantee to block until trigger_func is called, and |
| # trigger_func must guarantee to change queue state so that block_func can make |
| # enough progress to return. In particular, a block_func that just raises an |
| # exception regardless of whether trigger_func is called will lead to |
| # timing-dependent sporadic failures, and one of those went rarely seen but |
| # undiagnosed for years. Now block_func must be unexceptional. If block_func |
| # is supposed to raise an exception, call do_exceptional_blocking_test() |
| # instead. |
| |
| class BlockingTestMixin: |
| |
| def do_blocking_test(self, block_func, block_args, trigger_func, trigger_args): |
| self.t = _TriggerThread(trigger_func, trigger_args) |
| self.t.start() |
| self.result = block_func(*block_args) |
| # If block_func returned before our thread made the call, we failed! |
| if not self.t.startedEvent.is_set(): |
| self.fail("blocking function '%r' appeared not to block" % |
| block_func) |
| self.t.join(10) # make sure the thread terminates |
| if self.t.is_alive(): |
| self.fail("trigger function '%r' appeared to not return" % |
| trigger_func) |
| return self.result |
| |
| # Call this instead if block_func is supposed to raise an exception. |
| def do_exceptional_blocking_test(self,block_func, block_args, trigger_func, |
| trigger_args, expected_exception_class): |
| self.t = _TriggerThread(trigger_func, trigger_args) |
| self.t.start() |
| try: |
| try: |
| block_func(*block_args) |
| except expected_exception_class: |
| raise |
| else: |
| self.fail("expected exception of kind %r" % |
| expected_exception_class) |
| finally: |
| self.t.join(10) # make sure the thread terminates |
| if self.t.is_alive(): |
| self.fail("trigger function '%r' appeared to not return" % |
| trigger_func) |
| if not self.t.startedEvent.is_set(): |
| self.fail("trigger thread ended but event never set") |
| |
| |
| class BaseQueueTest(unittest.TestCase, BlockingTestMixin): |
| def setUp(self): |
| self.cum = 0 |
| self.cumlock = threading.Lock() |
| |
| def simple_queue_test(self, q): |
| if q.qsize(): |
| raise RuntimeError("Call this function with an empty queue") |
| self.assertTrue(q.empty()) |
| self.assertFalse(q.full()) |
| # I guess we better check things actually queue correctly a little :) |
| q.put(111) |
| q.put(333) |
| q.put(222) |
| target_order = dict(Queue = [111, 333, 222], |
| LifoQueue = [222, 333, 111], |
| PriorityQueue = [111, 222, 333]) |
| actual_order = [q.get(), q.get(), q.get()] |
| self.assertEquals(actual_order, target_order[q.__class__.__name__], |
| "Didn't seem to queue the correct data!") |
| for i in range(QUEUE_SIZE-1): |
| q.put(i) |
| self.assertTrue(q.qsize(), "Queue should not be empty") |
| self.assertTrue(not qfull(q), "Queue should not be full") |
| last = 2 * QUEUE_SIZE |
| full = 3 * 2 * QUEUE_SIZE |
| q.put(last) |
| self.assertTrue(qfull(q), "Queue should be full") |
| self.assertFalse(q.empty()) |
| self.assertTrue(q.full()) |
| try: |
| q.put(full, block=0) |
| self.fail("Didn't appear to block with a full queue") |
| except queue.Full: |
| pass |
| try: |
| q.put(full, timeout=0.01) |
| self.fail("Didn't appear to time-out with a full queue") |
| except queue.Full: |
| pass |
| # Test a blocking put |
| self.do_blocking_test(q.put, (full,), q.get, ()) |
| self.do_blocking_test(q.put, (full, True, 10), q.get, ()) |
| # Empty it |
| for i in range(QUEUE_SIZE): |
| q.get() |
| self.assertTrue(not q.qsize(), "Queue should be empty") |
| try: |
| q.get(block=0) |
| self.fail("Didn't appear to block with an empty queue") |
| except queue.Empty: |
| pass |
| try: |
| q.get(timeout=0.01) |
| self.fail("Didn't appear to time-out with an empty queue") |
| except queue.Empty: |
| pass |
| # Test a blocking get |
| self.do_blocking_test(q.get, (), q.put, ('empty',)) |
| self.do_blocking_test(q.get, (True, 10), q.put, ('empty',)) |
| |
| |
| def worker(self, q): |
| while True: |
| x = q.get() |
| if x < 0: |
| q.task_done() |
| return |
| with self.cumlock: |
| self.cum += x |
| q.task_done() |
| |
| def queue_join_test(self, q): |
| self.cum = 0 |
| for i in (0,1): |
| threading.Thread(target=self.worker, args=(q,)).start() |
| for i in range(100): |
| q.put(i) |
| q.join() |
| self.assertEquals(self.cum, sum(range(100)), |
| "q.join() did not block until all tasks were done") |
| for i in (0,1): |
| q.put(-1) # instruct the threads to close |
| q.join() # verify that you can join twice |
| |
| def test_queue_task_done(self): |
| # Test to make sure a queue task completed successfully. |
| q = self.type2test() |
| try: |
| q.task_done() |
| except ValueError: |
| pass |
| else: |
| self.fail("Did not detect task count going negative") |
| |
| def test_queue_join(self): |
| # Test that a queue join()s successfully, and before anything else |
| # (done twice for insurance). |
| q = self.type2test() |
| self.queue_join_test(q) |
| self.queue_join_test(q) |
| try: |
| q.task_done() |
| except ValueError: |
| pass |
| else: |
| self.fail("Did not detect task count going negative") |
| |
| def test_simple_queue(self): |
| # Do it a couple of times on the same queue. |
| # Done twice to make sure works with same instance reused. |
| q = self.type2test(QUEUE_SIZE) |
| self.simple_queue_test(q) |
| self.simple_queue_test(q) |
| |
| def test_negative_timeout_raises_exception(self): |
| q = self.type2test(QUEUE_SIZE) |
| with self.assertRaises(ValueError): |
| q.put(1, timeout=-1) |
| with self.assertRaises(ValueError): |
| q.get(1, timeout=-1) |
| |
| def test_nowait(self): |
| q = self.type2test(QUEUE_SIZE) |
| for i in range(QUEUE_SIZE): |
| q.put_nowait(1) |
| with self.assertRaises(queue.Full): |
| q.put_nowait(1) |
| |
| for i in range(QUEUE_SIZE): |
| q.get_nowait() |
| with self.assertRaises(queue.Empty): |
| q.get_nowait() |
| |
| |
| class QueueTest(BaseQueueTest): |
| type2test = queue.Queue |
| |
| class LifoQueueTest(BaseQueueTest): |
| type2test = queue.LifoQueue |
| |
| class PriorityQueueTest(BaseQueueTest): |
| type2test = queue.PriorityQueue |
| |
| |
| |
| # A Queue subclass that can provoke failure at a moment's notice :) |
| class FailingQueueException(Exception): |
| pass |
| |
| class FailingQueue(queue.Queue): |
| def __init__(self, *args): |
| self.fail_next_put = False |
| self.fail_next_get = False |
| queue.Queue.__init__(self, *args) |
| def _put(self, item): |
| if self.fail_next_put: |
| self.fail_next_put = False |
| raise FailingQueueException("You Lose") |
| return queue.Queue._put(self, item) |
| def _get(self): |
| if self.fail_next_get: |
| self.fail_next_get = False |
| raise FailingQueueException("You Lose") |
| return queue.Queue._get(self) |
| |
| class FailingQueueTest(unittest.TestCase, BlockingTestMixin): |
| |
| def failing_queue_test(self, q): |
| if q.qsize(): |
| raise RuntimeError("Call this function with an empty queue") |
| for i in range(QUEUE_SIZE-1): |
| q.put(i) |
| # Test a failing non-blocking put. |
| q.fail_next_put = True |
| try: |
| q.put("oops", block=0) |
| self.fail("The queue didn't fail when it should have") |
| except FailingQueueException: |
| pass |
| q.fail_next_put = True |
| try: |
| q.put("oops", timeout=0.1) |
| self.fail("The queue didn't fail when it should have") |
| except FailingQueueException: |
| pass |
| q.put("last") |
| self.assertTrue(qfull(q), "Queue should be full") |
| # Test a failing blocking put |
| q.fail_next_put = True |
| try: |
| self.do_blocking_test(q.put, ("full",), q.get, ()) |
| self.fail("The queue didn't fail when it should have") |
| except FailingQueueException: |
| pass |
| # Check the Queue isn't damaged. |
| # put failed, but get succeeded - re-add |
| q.put("last") |
| # Test a failing timeout put |
| q.fail_next_put = True |
| try: |
| self.do_exceptional_blocking_test(q.put, ("full", True, 10), q.get, (), |
| FailingQueueException) |
| self.fail("The queue didn't fail when it should have") |
| except FailingQueueException: |
| pass |
| # Check the Queue isn't damaged. |
| # put failed, but get succeeded - re-add |
| q.put("last") |
| self.assertTrue(qfull(q), "Queue should be full") |
| q.get() |
| self.assertTrue(not qfull(q), "Queue should not be full") |
| q.put("last") |
| self.assertTrue(qfull(q), "Queue should be full") |
| # Test a blocking put |
| self.do_blocking_test(q.put, ("full",), q.get, ()) |
| # Empty it |
| for i in range(QUEUE_SIZE): |
| q.get() |
| self.assertTrue(not q.qsize(), "Queue should be empty") |
| q.put("first") |
| q.fail_next_get = True |
| try: |
| q.get() |
| self.fail("The queue didn't fail when it should have") |
| except FailingQueueException: |
| pass |
| self.assertTrue(q.qsize(), "Queue should not be empty") |
| q.fail_next_get = True |
| try: |
| q.get(timeout=0.1) |
| self.fail("The queue didn't fail when it should have") |
| except FailingQueueException: |
| pass |
| self.assertTrue(q.qsize(), "Queue should not be empty") |
| q.get() |
| self.assertTrue(not q.qsize(), "Queue should be empty") |
| q.fail_next_get = True |
| try: |
| self.do_exceptional_blocking_test(q.get, (), q.put, ('empty',), |
| FailingQueueException) |
| self.fail("The queue didn't fail when it should have") |
| except FailingQueueException: |
| pass |
| # put succeeded, but get failed. |
| self.assertTrue(q.qsize(), "Queue should not be empty") |
| q.get() |
| self.assertTrue(not q.qsize(), "Queue should be empty") |
| |
| def test_failing_queue(self): |
| # Test to make sure a queue is functioning correctly. |
| # Done twice to the same instance. |
| q = FailingQueue(QUEUE_SIZE) |
| self.failing_queue_test(q) |
| self.failing_queue_test(q) |
| |
| |
| def test_main(): |
| support.run_unittest(QueueTest, LifoQueueTest, PriorityQueueTest, |
| FailingQueueTest) |
| |
| |
| if __name__ == "__main__": |
| test_main() |