/python/Lib/test/test_thread.py
Python | 261 lines | 204 code | 42 blank | 15 comment | 38 complexity | 3bf6cfc1b5e84e86ec7862166d4fb361 MD5 | raw file
- import os
- import unittest
- import random
- from test import test_support
- thread = test_support.import_module('thread')
- import time
- import sys
- import weakref
- from test import lock_tests
- NUMTASKS = 10
- NUMTRIPS = 3
- _print_mutex = thread.allocate_lock()
- def verbose_print(arg):
- """Helper function for printing out debugging output."""
- if test_support.verbose:
- with _print_mutex:
- print arg
- class BasicThreadTest(unittest.TestCase):
- def setUp(self):
- self.done_mutex = thread.allocate_lock()
- self.done_mutex.acquire()
- self.running_mutex = thread.allocate_lock()
- self.random_mutex = thread.allocate_lock()
- self.created = 0
- self.running = 0
- self.next_ident = 0
- class ThreadRunningTests(BasicThreadTest):
- def newtask(self):
- with self.running_mutex:
- self.next_ident += 1
- verbose_print("creating task %s" % self.next_ident)
- thread.start_new_thread(self.task, (self.next_ident,))
- self.created += 1
- self.running += 1
- def task(self, ident):
- with self.random_mutex:
- delay = random.random() / 10000.0
- verbose_print("task %s will run for %sus" % (ident, round(delay*1e6)))
- time.sleep(delay)
- verbose_print("task %s done" % ident)
- with self.running_mutex:
- self.running -= 1
- if self.created == NUMTASKS and self.running == 0:
- self.done_mutex.release()
- def test_starting_threads(self):
- # Basic test for thread creation.
- for i in range(NUMTASKS):
- self.newtask()
- verbose_print("waiting for tasks to complete...")
- self.done_mutex.acquire()
- verbose_print("all tasks done")
- def test_stack_size(self):
- # Various stack size tests.
- self.assertEqual(thread.stack_size(), 0, "initial stack size is not 0")
- thread.stack_size(0)
- self.assertEqual(thread.stack_size(), 0, "stack_size not reset to default")
- @unittest.skipIf(os.name not in ("nt", "os2", "posix"), 'test meant for nt, os2, and posix')
- def test_nt_and_posix_stack_size(self):
- try:
- thread.stack_size(4096)
- except ValueError:
- verbose_print("caught expected ValueError setting "
- "stack_size(4096)")
- except thread.error:
- self.skipTest("platform does not support changing thread stack "
- "size")
- fail_msg = "stack_size(%d) failed - should succeed"
- for tss in (262144, 0x100000, 0):
- thread.stack_size(tss)
- self.assertEqual(thread.stack_size(), tss, fail_msg % tss)
- verbose_print("successfully set stack_size(%d)" % tss)
- for tss in (262144, 0x100000):
- verbose_print("trying stack_size = (%d)" % tss)
- self.next_ident = 0
- self.created = 0
- for i in range(NUMTASKS):
- self.newtask()
- verbose_print("waiting for all tasks to complete")
- self.done_mutex.acquire()
- verbose_print("all tasks done")
- thread.stack_size(0)
- def test__count(self):
- # Test the _count() function.
- orig = thread._count()
- mut = thread.allocate_lock()
- mut.acquire()
- started = []
- def task():
- started.append(None)
- mut.acquire()
- mut.release()
- thread.start_new_thread(task, ())
- while not started:
- time.sleep(0.01)
- self.assertEqual(thread._count(), orig + 1)
- # Allow the task to finish.
- mut.release()
- # The only reliable way to be sure that the thread ended from the
- # interpreter's point of view is to wait for the function object to be
- # destroyed.
- done = []
- wr = weakref.ref(task, lambda _: done.append(None))
- del task
- while not done:
- time.sleep(0.01)
- self.assertEqual(thread._count(), orig)
- def test_save_exception_state_on_error(self):
- # See issue #14474
- def task():
- started.release()
- raise SyntaxError
- def mywrite(self, *args):
- try:
- raise ValueError
- except ValueError:
- pass
- real_write(self, *args)
- c = thread._count()
- started = thread.allocate_lock()
- with test_support.captured_output("stderr") as stderr:
- real_write = stderr.write
- stderr.write = mywrite
- started.acquire()
- thread.start_new_thread(task, ())
- started.acquire()
- while thread._count() > c:
- time.sleep(0.01)
- self.assertIn("Traceback", stderr.getvalue())
- class Barrier:
- def __init__(self, num_threads):
- self.num_threads = num_threads
- self.waiting = 0
- self.checkin_mutex = thread.allocate_lock()
- self.checkout_mutex = thread.allocate_lock()
- self.checkout_mutex.acquire()
- def enter(self):
- self.checkin_mutex.acquire()
- self.waiting = self.waiting + 1
- if self.waiting == self.num_threads:
- self.waiting = self.num_threads - 1
- self.checkout_mutex.release()
- return
- self.checkin_mutex.release()
- self.checkout_mutex.acquire()
- self.waiting = self.waiting - 1
- if self.waiting == 0:
- self.checkin_mutex.release()
- return
- self.checkout_mutex.release()
- class BarrierTest(BasicThreadTest):
- def test_barrier(self):
- self.bar = Barrier(NUMTASKS)
- self.running = NUMTASKS
- for i in range(NUMTASKS):
- thread.start_new_thread(self.task2, (i,))
- verbose_print("waiting for tasks to end")
- self.done_mutex.acquire()
- verbose_print("tasks done")
- def task2(self, ident):
- for i in range(NUMTRIPS):
- if ident == 0:
- # give it a good chance to enter the next
- # barrier before the others are all out
- # of the current one
- delay = 0
- else:
- with self.random_mutex:
- delay = random.random() / 10000.0
- verbose_print("task %s will run for %sus" %
- (ident, round(delay * 1e6)))
- time.sleep(delay)
- verbose_print("task %s entering %s" % (ident, i))
- self.bar.enter()
- verbose_print("task %s leaving barrier" % ident)
- with self.running_mutex:
- self.running -= 1
- # Must release mutex before releasing done, else the main thread can
- # exit and set mutex to None as part of global teardown; then
- # mutex.release() raises AttributeError.
- finished = self.running == 0
- if finished:
- self.done_mutex.release()
- class LockTests(lock_tests.LockTests):
- locktype = thread.allocate_lock
- class TestForkInThread(unittest.TestCase):
- def setUp(self):
- self.read_fd, self.write_fd = os.pipe()
- @unittest.skipIf(sys.platform.startswith('win'),
- "This test is only appropriate for POSIX-like systems.")
- @test_support.reap_threads
- def test_forkinthread(self):
- def thread1():
- try:
- pid = os.fork() # fork in a thread
- except RuntimeError:
- sys.exit(0) # exit the child
- if pid == 0: # child
- os.close(self.read_fd)
- os.write(self.write_fd, "OK")
- sys.exit(0)
- else: # parent
- os.close(self.write_fd)
- thread.start_new_thread(thread1, ())
- self.assertEqual(os.read(self.read_fd, 2), "OK",
- "Unable to fork() in thread")
- def tearDown(self):
- try:
- os.close(self.read_fd)
- except OSError:
- pass
- try:
- os.close(self.write_fd)
- except OSError:
- pass
- def test_main():
- test_support.run_unittest(ThreadRunningTests, BarrierTest, LockTests,
- TestForkInThread)
- if __name__ == "__main__":
- test_main()