bpo-38614: Use test.support.SHORT_TIMEOUT constant (GH-17566)

Replace hardcoded timeout constants in tests with SHORT_TIMEOUT of
test.support, so it's easier to ajdust this timeout for all tests at
once.

SHORT_TIMEOUT is 30 seconds by default, but it can be longer
depending on --timeout command line option.

The change makes almost all timeouts longer, except
test_reap_children() of test_support which is made 2x shorter:
SHORT_TIMEOUT should be enough. If this test starts to fail,
LONG_TIMEOUT should be used instead.

Uniformize also "from test import support" import in some test files.

Lib/test/_test_multiprocessing.py

@@ -318,7 +318,7 @@ class _TestProcess(BaseTestCase):
     def _test_report_parent_status(cls, wconn):
         from multiprocessing.process import parent_process
         wconn.send("alive" if parent_process().is_alive() else "not alive")
-        parent_process().join(timeout=5)
+        parent_process().join(timeout=support.SHORT_TIMEOUT)
         wconn.send("alive" if parent_process().is_alive() else "not alive")
 
     def test_process(self):

Lib/test/fork_wait.py

@@ -11,7 +11,7 @@ active threads survive in the child after a fork(); this is an error.
 
 import os, sys, time, unittest
 import threading
-import test.support as support
+from test import support
 
 
 LONGSLEEP = 2
@@ -62,7 +62,7 @@ class ForkWait(unittest.TestCase):
             self.threads.append(thread)
 
         # busy-loop to wait for threads
-        deadline = time.monotonic() + 10.0
+        deadline = time.monotonic() + support.SHORT_TIMEOUT
         while len(self.alive) < NUM_THREADS:
             time.sleep(0.1)
             if deadline < time.monotonic():

Lib/test/signalinterproctester.py

@@ -4,6 +4,7 @@ import subprocess
 import sys
 import time
 import unittest
+from test import support
 
 
 class SIGUSR1Exception(Exception):
@@ -27,7 +28,7 @@ class InterProcessSignalTests(unittest.TestCase):
             # (if set)
             child.wait()
 
-        timeout = 10.0
+        timeout = support.SHORT_TIMEOUT
         deadline = time.monotonic() + timeout
 
         while time.monotonic() < deadline:

Lib/test/test_asyncio/test_events.py

@@ -1475,12 +1475,12 @@ class EventLoopTestsMixin:
             return len(data)
 
         test_utils.run_until(self.loop, lambda: reader(data) >= 1,
-                             timeout=10)
+                             timeout=support.SHORT_TIMEOUT)
         self.assertEqual(b'1', data)
 
         transport.write(b'2345')
         test_utils.run_until(self.loop, lambda: reader(data) >= 5,
-                             timeout=10)
+                             timeout=support.SHORT_TIMEOUT)
         self.assertEqual(b'12345', data)
         self.assertEqual('CONNECTED', proto.state)
 
@@ -1531,27 +1531,29 @@ class EventLoopTestsMixin:
             return len(data)
 
         write_transport.write(b'1')
-        test_utils.run_until(self.loop, lambda: reader(data) >= 1, timeout=10)
+        test_utils.run_until(self.loop, lambda: reader(data) >= 1,
+                             timeout=support.SHORT_TIMEOUT)
         self.assertEqual(b'1', data)
         self.assertEqual(['INITIAL', 'CONNECTED'], read_proto.state)
         self.assertEqual('CONNECTED', write_proto.state)
 
         os.write(master, b'a')
         test_utils.run_until(self.loop, lambda: read_proto.nbytes >= 1,
-                             timeout=10)
+                             timeout=support.SHORT_TIMEOUT)
         self.assertEqual(['INITIAL', 'CONNECTED'], read_proto.state)
         self.assertEqual(1, read_proto.nbytes)
         self.assertEqual('CONNECTED', write_proto.state)
 
         write_transport.write(b'2345')
-        test_utils.run_until(self.loop, lambda: reader(data) >= 5, timeout=10)
+        test_utils.run_until(self.loop, lambda: reader(data) >= 5,
+                             timeout=support.SHORT_TIMEOUT)
         self.assertEqual(b'12345', data)
         self.assertEqual(['INITIAL', 'CONNECTED'], read_proto.state)
         self.assertEqual('CONNECTED', write_proto.state)
 
         os.write(master, b'bcde')
         test_utils.run_until(self.loop, lambda: read_proto.nbytes >= 5,
-                             timeout=10)
+                             timeout=support.SHORT_TIMEOUT)
         self.assertEqual(['INITIAL', 'CONNECTED'], read_proto.state)
         self.assertEqual(5, read_proto.nbytes)
         self.assertEqual('CONNECTED', write_proto.state)

Lib/test/test_asyncio/test_sslproto.py

@@ -274,7 +274,8 @@ class BaseStartTLS(func_tests.FunctionalTestCaseMixin):
 
         with self.tcp_server(serve, timeout=self.TIMEOUT) as srv:
             self.loop.run_until_complete(
-                asyncio.wait_for(client(srv.addr), timeout=10))
+                asyncio.wait_for(client(srv.addr),
+                                 timeout=support.SHORT_TIMEOUT))
 
         # No garbage is left if SSL is closed uncleanly
         client_context = weakref.ref(client_context)
@@ -335,7 +336,8 @@ class BaseStartTLS(func_tests.FunctionalTestCaseMixin):
 
         with self.tcp_server(serve, timeout=self.TIMEOUT) as srv:
             self.loop.run_until_complete(
-                asyncio.wait_for(client(srv.addr), timeout=10))
+                asyncio.wait_for(client(srv.addr),
+                                 timeout=support.SHORT_TIMEOUT))
 
         # No garbage is left for SSL client from loop.create_connection, even
         # if user stores the SSLTransport in corresponding protocol instance
@@ -491,7 +493,8 @@ class BaseStartTLS(func_tests.FunctionalTestCaseMixin):
 
         with self.tcp_server(serve, timeout=self.TIMEOUT) as srv:
             self.loop.run_until_complete(
-                asyncio.wait_for(client(srv.addr), timeout=10))
+                asyncio.wait_for(client(srv.addr),
+                                 timeout=support.SHORT_TIMEOUT))
 
     def test_start_tls_server_1(self):
         HELLO_MSG = b'1' * self.PAYLOAD_SIZE
@@ -619,7 +622,7 @@ class BaseStartTLS(func_tests.FunctionalTestCaseMixin):
                     *addr,
                     ssl=client_sslctx,
                     server_hostname='',
-                    ssl_handshake_timeout=10.0),
+                    ssl_handshake_timeout=support.SHORT_TIMEOUT),
                 0.5)
 
         with self.tcp_server(server,

Lib/test/test_asyncio/utils.py

@@ -107,7 +107,7 @@ def run_briefly(loop):
         gen.close()
 
 
-def run_until(loop, pred, timeout=30):
+def run_until(loop, pred, timeout=support.SHORT_TIMEOUT):
     deadline = time.monotonic() + timeout
     while not pred():
         if timeout is not None:

Lib/test/test_concurrent_futures.py

@@ -1,9 +1,9 @@
-import test.support
+from test import support
 
 # Skip tests if _multiprocessing wasn't built.
-test.support.import_module('_multiprocessing')
+support.import_module('_multiprocessing')
 # Skip tests if sem_open implementation is broken.
-test.support.import_module('multiprocessing.synchronize')
+support.import_module('multiprocessing.synchronize')
 
 from test.support.script_helper import assert_python_ok
 
@@ -101,11 +101,11 @@ def make_dummy_object(_):
 
 class BaseTestCase(unittest.TestCase):
     def setUp(self):
-        self._thread_key = test.support.threading_setup()
+        self._thread_key = support.threading_setup()
 
     def tearDown(self):
-        test.support.reap_children()
-        test.support.threading_cleanup(*self._thread_key)
+        support.reap_children()
+        support.threading_cleanup(*self._thread_key)
 
 
 class ExecutorMixin:
@@ -132,7 +132,7 @@ class ExecutorMixin:
         self.executor = None
 
         dt = time.monotonic() - self.t1
-        if test.support.verbose:
+        if support.verbose:
             print("%.2fs" % dt, end=' ')
         self.assertLess(dt, 300, "synchronization issue: test lasted too long")
 
@@ -712,7 +712,7 @@ class ExecutorTest:
         self.executor.map(str, [2] * (self.worker_count + 1))
         self.executor.shutdown()
 
-    @test.support.cpython_only
+    @support.cpython_only
     def test_no_stale_references(self):
         # Issue #16284: check that the executors don't unnecessarily hang onto
         # references.
@@ -724,7 +724,7 @@ class ExecutorTest:
         self.executor.submit(my_object.my_method)
         del my_object
 
-        collected = my_object_collected.wait(timeout=5.0)
+        collected = my_object_collected.wait(timeout=support.SHORT_TIMEOUT)
         self.assertTrue(collected,
                         "Stale reference not collected within timeout.")
 
@@ -836,7 +836,7 @@ class ProcessPoolExecutorTest(ExecutorTest):
         self.assertIs(type(cause), futures.process._RemoteTraceback)
         self.assertIn('raise RuntimeError(123) # some comment', cause.tb)
 
-        with test.support.captured_stderr() as f1:
+        with support.captured_stderr() as f1:
             try:
                 raise exc
             except RuntimeError:
@@ -929,7 +929,7 @@ class ErrorAtUnpickle(object):
 
 
 class ExecutorDeadlockTest:
-    TIMEOUT = 15
+    TIMEOUT = support.SHORT_TIMEOUT
 
     @classmethod
     def _sleep_id(cls, x, delay):
@@ -994,7 +994,7 @@ class ExecutorDeadlockTest:
         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():
+                with support.captured_stderr():
                     executor = self.executor_type(
                         max_workers=2, mp_context=get_context(self.ctx))
                     res = executor.submit(func, *args)
@@ -1061,7 +1061,7 @@ class FutureTests(BaseTestCase):
         self.assertTrue(was_cancelled)
 
     def test_done_callback_raises(self):
-        with test.support.captured_stderr() as stderr:
+        with support.captured_stderr() as stderr:
             raising_was_called = False
             fn_was_called = False
 
@@ -1116,7 +1116,7 @@ class FutureTests(BaseTestCase):
         self.assertTrue(was_cancelled)
 
     def test_done_callback_raises_already_succeeded(self):
-        with test.support.captured_stderr() as stderr:
+        with support.captured_stderr() as stderr:
             def raising_fn(callback_future):
                 raise Exception('doh!')
 
@@ -1235,7 +1235,8 @@ class FutureTests(BaseTestCase):
         t = threading.Thread(target=notification)
         t.start()
 
-        self.assertRaises(futures.CancelledError, f1.result, timeout=5)
+        self.assertRaises(futures.CancelledError,
+                          f1.result, timeout=support.SHORT_TIMEOUT)
         t.join()
 
     def test_exception_with_timeout(self):
@@ -1264,7 +1265,7 @@ class FutureTests(BaseTestCase):
         t = threading.Thread(target=notification)
         t.start()
 
-        self.assertTrue(isinstance(f1.exception(timeout=5), OSError))
+        self.assertTrue(isinstance(f1.exception(timeout=support.SHORT_TIMEOUT), OSError))
         t.join()
 
     def test_multiple_set_result(self):
@@ -1300,12 +1301,12 @@ _threads_key = None
 
 def setUpModule():
     global _threads_key
-    _threads_key = test.support.threading_setup()
+    _threads_key = support.threading_setup()
 
 
 def tearDownModule():
-    test.support.threading_cleanup(*_threads_key)
-    test.support.reap_children()
+    support.threading_cleanup(*_threads_key)
+    support.reap_children()
 
     # cleanup multiprocessing
     multiprocessing.process._cleanup()
@@ -1315,7 +1316,7 @@ def tearDownModule():
     # bpo-37421: Explicitly call _run_finalizers() to remove immediately
     # temporary directories created by multiprocessing.util.get_temp_dir().
     multiprocessing.util._run_finalizers()
-    test.support.gc_collect()
+    support.gc_collect()
 
 
 if __name__ == "__main__":

Lib/test/test_fork1.py

@@ -10,15 +10,15 @@ import time
 import unittest
 
 from test.fork_wait import ForkWait
-from test.support import reap_children, get_attribute, verbose
+from test import support
 
 
 # Skip test if fork does not exist.
-get_attribute(os, 'fork')
+support.get_attribute(os, 'fork')
 
 class ForkTest(ForkWait):
     def wait_impl(self, cpid):
-        deadline = time.monotonic() + 10.0
+        deadline = time.monotonic() + support.SHORT_TIMEOUT
         while time.monotonic() <= deadline:
             # waitpid() shouldn't hang, but some of the buildbots seem to hang
             # in the forking tests.  This is an attempt to fix the problem.
@@ -56,7 +56,7 @@ class ForkTest(ForkWait):
                 if m == complete_module:
                     os._exit(0)
                 else:
-                    if verbose > 1:
+                    if support.verbose > 1:
                         print("Child encountered partial module")
                     os._exit(1)
             else:
@@ -90,7 +90,7 @@ class ForkTest(ForkWait):
                         imp.release_lock()
             except RuntimeError:
                 if in_child:
-                    if verbose > 1:
+                    if support.verbose > 1:
                         print("RuntimeError in child")
                     os._exit(1)
                 raise
@@ -105,7 +105,7 @@ class ForkTest(ForkWait):
 
 
 def tearDownModule():
-    reap_children()
+    support.reap_children()
 
 if __name__ == "__main__":
     unittest.main()

Lib/test/test_pydoc.py

@@ -1336,7 +1336,7 @@ class PydocServerTest(unittest.TestCase):
         self.assertIn('0.0.0.0', serverthread.docserver.address)
 
         starttime = time.monotonic()
-        timeout = 1  #seconds
+        timeout = test.support.SHORT_TIMEOUT
 
         while serverthread.serving:
             time.sleep(.01)

Lib/test/test_sched.py

@@ -6,7 +6,7 @@ import unittest
 from test import support
 
 
-TIMEOUT = 10
+TIMEOUT = support.SHORT_TIMEOUT
 
 
 class Timer:

Lib/test/test_signal.py

@@ -644,7 +644,7 @@ class SiginterruptTest(unittest.TestCase):
                 # wait until the child process is loaded and has started
                 first_line = process.stdout.readline()
 
-                stdout, stderr = process.communicate(timeout=5.0)
+                stdout, stderr = process.communicate(timeout=support.SHORT_TIMEOUT)
             except subprocess.TimeoutExpired:
                 process.kill()
                 return False
@@ -1192,7 +1192,7 @@ class StressTest(unittest.TestCase):
         self.setsig(signal.SIGALRM, second_handler)  # for ITIMER_REAL
 
         expected_sigs = 0
-        deadline = time.monotonic() + 15.0
+        deadline = time.monotonic() + support.SHORT_TIMEOUT
 
         while expected_sigs < N:
             os.kill(os.getpid(), signal.SIGPROF)
@@ -1226,7 +1226,7 @@ class StressTest(unittest.TestCase):
         self.setsig(signal.SIGALRM, handler)  # for ITIMER_REAL
 
         expected_sigs = 0
-        deadline = time.monotonic() + 15.0
+        deadline = time.monotonic() + support.SHORT_TIMEOUT
 
         while expected_sigs < N:
             # Hopefully the SIGALRM will be received somewhere during

Lib/test/test_socketserver.py

@@ -36,7 +36,7 @@ def signal_alarm(n):
 # Remember real select() to avoid interferences with mocking
 _real_select = select.select
 
-def receive(sock, n, timeout=20):
+def receive(sock, n, timeout=test.support.SHORT_TIMEOUT):
     r, w, x = _real_select([sock], [], [], timeout)
     if sock in r:
         return sock.recv(n)

Lib/test/test_ssl.py

@@ -2156,7 +2156,7 @@ class SimpleBackgroundTests(unittest.TestCase):
     def ssl_io_loop(self, sock, incoming, outgoing, func, *args, **kwargs):
         # A simple IO loop. Call func(*args) depending on the error we get
         # (WANT_READ or WANT_WRITE) move data between the socket and the BIOs.
-        timeout = kwargs.get('timeout', 10)
+        timeout = kwargs.get('timeout', support.SHORT_TIMEOUT)
         deadline = time.monotonic() + timeout
         count = 0
         while True:

Lib/test/test_subprocess.py

@@ -1121,9 +1121,7 @@ class ProcessTestCase(BaseTestCase):
         with self.assertRaises(subprocess.TimeoutExpired) as c:
             p.wait(timeout=0.0001)
         self.assertIn("0.0001", str(c.exception))  # For coverage of __str__.
-        # Some heavily loaded buildbots (sparc Debian 3.x) require this much
-        # time to start.
-        self.assertEqual(p.wait(timeout=3), 0)
+        self.assertEqual(p.wait(timeout=support.SHORT_TIMEOUT), 0)
 
     def test_invalid_bufsize(self):
         # an invalid type of the bufsize argument should raise
@@ -1289,7 +1287,7 @@ class ProcessTestCase(BaseTestCase):
         # Wait for the process to finish; the thread should kill it
         # long before it finishes on its own.  Supplying a timeout
         # triggers a different code path for better coverage.
-        proc.wait(timeout=20)
+        proc.wait(timeout=support.SHORT_TIMEOUT)
         self.assertEqual(proc.returncode, expected_errorcode,
                          msg="unexpected result in wait from main thread")
 

Lib/test/test_support.py

@@ -422,7 +422,7 @@ class TestSupport(unittest.TestCase):
             os._exit(0)
 
         t0 = time.monotonic()
-        deadline = time.monotonic() + 60.0
+        deadline = time.monotonic() + support.SHORT_TIMEOUT
 
         was_altered = support.environment_altered
         try:

Lib/test/test_threading.py

@@ -265,7 +265,7 @@ class ThreadTests(BaseTestCase):
         self.assertEqual(result, 1) # one thread state modified
         if verbose:
             print("    waiting for worker to say it caught the exception")
-        worker_saw_exception.wait(timeout=10)
+        worker_saw_exception.wait(timeout=support.SHORT_TIMEOUT)
         self.assertTrue(t.finished)
         if verbose:
             print("    all OK -- joining worker")
@@ -640,7 +640,7 @@ class ThreadTests(BaseTestCase):
         finish.release()
         # When the thread ends, the state_lock can be successfully
         # acquired.
-        self.assertTrue(tstate_lock.acquire(timeout=5), False)
+        self.assertTrue(tstate_lock.acquire(timeout=support.SHORT_TIMEOUT), False)
         # But is_alive() is still True:  we hold _tstate_lock now, which
         # prevents is_alive() from knowing the thread's end-of-life C code
         # is done.

Lib/test/test_wait3.py

@@ -7,7 +7,7 @@ import sys
 import time
 import unittest
 from test.fork_wait import ForkWait
-from test.support import reap_children
+from test import support
 
 if not hasattr(os, 'fork'):
     raise unittest.SkipTest("os.fork not defined")
@@ -20,7 +20,7 @@ class Wait3Test(ForkWait):
         # This many iterations can be required, since some previously run
         # tests (e.g. test_ctypes) could have spawned a lot of children
         # very quickly.
-        deadline = time.monotonic() + 10.0
+        deadline = time.monotonic() + support.SHORT_TIMEOUT
         while time.monotonic() <= deadline:
             # wait3() shouldn't hang, but some of the buildbots seem to hang
             # in the forking tests.  This is an attempt to fix the problem.
@@ -50,7 +50,7 @@ class Wait3Test(ForkWait):
 
 
 def tearDownModule():
-    reap_children()
+    support.reap_children()
 
 if __name__ == "__main__":
     unittest.main()

Lib/test/test_wait4.py

@@ -6,11 +6,11 @@ import time
 import sys
 import unittest
 from test.fork_wait import ForkWait
-from test.support import reap_children, get_attribute
+from test import support
 
 # If either of these do not exist, skip this test.
-get_attribute(os, 'fork')
-get_attribute(os, 'wait4')
+support.get_attribute(os, 'fork')
+support.get_attribute(os, 'wait4')
 
 
 class Wait4Test(ForkWait):
@@ -20,7 +20,7 @@ class Wait4Test(ForkWait):
             # Issue #11185: wait4 is broken on AIX and will always return 0
             # with WNOHANG.
             option = 0
-        deadline = time.monotonic() + 10.0
+        deadline = time.monotonic() + support.SHORT_TIMEOUT
         while time.monotonic() <= deadline:
             # wait4() shouldn't hang, but some of the buildbots seem to hang
             # in the forking tests.  This is an attempt to fix the problem.
@@ -33,7 +33,7 @@ class Wait4Test(ForkWait):
         self.assertTrue(rusage)
 
 def tearDownModule():
-    reap_children()
+    support.reap_children()
 
 if __name__ == "__main__":
     unittest.main()

Misc/NEWS.d/next/Tests/2019-12-10-14-26-23.bpo-38614.89JpNh.rst

@@ -1,3 +1,6 @@
 Replace hardcoded timeout constants in tests with
-:data:`~test.support.LOOPBACK_TIMEOUT` of :mod:`test.support`, so it's easier
-to ajdust this timeout for all tests at once.
+new :mod:`test.support` constants: :data:`~test.support.LOOPBACK_TIMEOUT`,
+:data:`~test.support.INTERNET_TIMEOUT`, :data:`~test.support.SHORT_TIMEOUT` and
+:data:`~test.support.LONG_TIMEOUT`. It becomes easier to adjust these four
+timeout constants for all tests at once, rather than having to adjust every
+single test file.