import threading
import time
import unittest
from concurrent import futures
from concurrent.futures._base import (
PENDING, RUNNING, CANCELLED, CANCELLED_AND_NOTIFIED, FINISHED, Future)
from test import support
from .util import (
PENDING_FUTURE, RUNNING_FUTURE, CANCELLED_FUTURE,
CANCELLED_AND_NOTIFIED_FUTURE, EXCEPTION_FUTURE, SUCCESSFUL_FUTURE,
BaseTestCase, create_future, setup_module)
class FutureTests(BaseTestCase):
def test_done_callback_with_result(self):
callback_result = None
def fn(callback_future):
nonlocal callback_result
callback_result = callback_future.result()
f = Future()
f.add_done_callback(fn)
f.set_result(5)
self.assertEqual(5, callback_result)
def test_done_callback_with_exception(self):
callback_exception = None
def fn(callback_future):
nonlocal callback_exception
callback_exception = callback_future.exception()
f = Future()
f.add_done_callback(fn)
f.set_exception(Exception('test'))
self.assertEqual(('test',), callback_exception.args)
def test_done_callback_with_cancel(self):
was_cancelled = None
def fn(callback_future):
nonlocal was_cancelled
was_cancelled = callback_future.cancelled()
f = Future()
f.add_done_callback(fn)
self.assertTrue(f.cancel())
self.assertTrue(was_cancelled)
def test_done_callback_raises(self):
with support.captured_stderr() as stderr:
raising_was_called = False
fn_was_called = False
def raising_fn(callback_future):
nonlocal raising_was_called
raising_was_called = True
raise Exception('doh!')
def fn(callback_future):
nonlocal fn_was_called
fn_was_called = True
f = Future()
f.add_done_callback(raising_fn)
f.add_done_callback(fn)
f.set_result(5)
self.assertTrue(raising_was_called)
self.assertTrue(fn_was_called)
self.assertIn('Exception: doh!', stderr.getvalue())
def test_done_callback_already_successful(self):
callback_result = None
def fn(callback_future):
nonlocal callback_result
callback_result = callback_future.result()
f = Future()
f.set_result(5)
f.add_done_callback(fn)
self.assertEqual(5, callback_result)
def test_done_callback_already_failed(self):
callback_exception = None
def fn(callback_future):
nonlocal callback_exception
callback_exception = callback_future.exception()
f = Future()
f.set_exception(Exception('test'))
f.add_done_callback(fn)
self.assertEqual(('test',), callback_exception.args)
def test_done_callback_already_cancelled(self):
was_cancelled = None
def fn(callback_future):
nonlocal was_cancelled
was_cancelled = callback_future.cancelled()
f = Future()
self.assertTrue(f.cancel())
f.add_done_callback(fn)
self.assertTrue(was_cancelled)
def test_done_callback_raises_already_succeeded(self):
with support.captured_stderr() as stderr:
def raising_fn(callback_future):
raise Exception('doh!')
f = Future()
# Set the result first to simulate a future that runs instantly,
# effectively allowing the callback to be run immediately.
f.set_result(5)
f.add_done_callback(raising_fn)
self.assertIn('exception calling callback for', stderr.getvalue())
self.assertIn('doh!', stderr.getvalue())
def test_repr(self):
self.assertRegex(repr(PENDING_FUTURE),
'<Future at 0x[0-9a-f]+ state=pending>')
self.assertRegex(repr(RUNNING_FUTURE),
'<Future at 0x[0-9a-f]+ state=running>')
self.assertRegex(repr(CANCELLED_FUTURE),
'<Future at 0x[0-9a-f]+ state=cancelled>')
self.assertRegex(repr(CANCELLED_AND_NOTIFIED_FUTURE),
'<Future at 0x[0-9a-f]+ state=cancelled>')
self.assertRegex(
repr(EXCEPTION_FUTURE),
'<Future at 0x[0-9a-f]+ state=finished raised OSError>')
self.assertRegex(
repr(SUCCESSFUL_FUTURE),
'<Future at 0x[0-9a-f]+ state=finished returned int>')
def test_cancel(self):
f1 = create_future(state=PENDING)
f2 = create_future(state=RUNNING)
f3 = create_future(state=CANCELLED)
f4 = create_future(state=CANCELLED_AND_NOTIFIED)
f5 = create_future(state=FINISHED, exception=OSError())
f6 = create_future(state=FINISHED, result=5)
self.assertTrue(f1.cancel())
self.assertEqual(f1._state, CANCELLED)
self.assertFalse(f2.cancel())
self.assertEqual(f2._state, RUNNING)
self.assertTrue(f3.cancel())
self.assertEqual(f3._state, CANCELLED)
self.assertTrue(f4.cancel())
self.assertEqual(f4._state, CANCELLED_AND_NOTIFIED)
self.assertFalse(f5.cancel())
self.assertEqual(f5._state, FINISHED)
self.assertFalse(f6.cancel())
self.assertEqual(f6._state, FINISHED)
def test_cancelled(self):
self.assertFalse(PENDING_FUTURE.cancelled())
self.assertFalse(RUNNING_FUTURE.cancelled())
self.assertTrue(CANCELLED_FUTURE.cancelled())
self.assertTrue(CANCELLED_AND_NOTIFIED_FUTURE.cancelled())
self.assertFalse(EXCEPTION_FUTURE.cancelled())
self.assertFalse(SUCCESSFUL_FUTURE.cancelled())
def test_done(self):
self.assertFalse(PENDING_FUTURE.done())
self.assertFalse(RUNNING_FUTURE.done())
self.assertTrue(CANCELLED_FUTURE.done())
self.assertTrue(CANCELLED_AND_NOTIFIED_FUTURE.done())
self.assertTrue(EXCEPTION_FUTURE.done())
self.assertTrue(SUCCESSFUL_FUTURE.done())
def test_running(self):
self.assertFalse(PENDING_FUTURE.running())
self.assertTrue(RUNNING_FUTURE.running())
self.assertFalse(CANCELLED_FUTURE.running())
self.assertFalse(CANCELLED_AND_NOTIFIED_FUTURE.running())
self.assertFalse(EXCEPTION_FUTURE.running())
self.assertFalse(SUCCESSFUL_FUTURE.running())
def test_result_with_timeout(self):
self.assertRaises(futures.TimeoutError,
PENDING_FUTURE.result, timeout=0)
self.assertRaises(futures.TimeoutError,
RUNNING_FUTURE.result, timeout=0)
self.assertRaises(futures.CancelledError,
CANCELLED_FUTURE.result, timeout=0)
self.assertRaises(futures.CancelledError,
CANCELLED_AND_NOTIFIED_FUTURE.result, timeout=0)
self.assertRaises(OSError, EXCEPTION_FUTURE.result, timeout=0)
self.assertEqual(SUCCESSFUL_FUTURE.result(timeout=0), 42)
def test_result_with_success(self):
# TODO([email protected]): This test is timing dependent.
def notification():
# Wait until the main thread is waiting for the result.
time.sleep(1)
f1.set_result(42)
f1 = create_future(state=PENDING)
t = threading.Thread(target=notification)
t.start()
self.assertEqual(f1.result(timeout=5), 42)
t.join()
def test_result_with_cancel(self):
# TODO([email protected]): This test is timing dependent.
def notification():
# Wait until the main thread is waiting for the result.
time.sleep(1)
f1.cancel()
f1 = create_future(state=PENDING)
t = threading.Thread(target=notification)
t.start()
self.assertRaises(futures.CancelledError,
f1.result, timeout=support.SHORT_TIMEOUT)
t.join()
def test_exception_with_timeout(self):
self.assertRaises(futures.TimeoutError,
PENDING_FUTURE.exception, timeout=0)
self.assertRaises(futures.TimeoutError,
RUNNING_FUTURE.exception, timeout=0)
self.assertRaises(futures.CancelledError,
CANCELLED_FUTURE.exception, timeout=0)
self.assertRaises(futures.CancelledError,
CANCELLED_AND_NOTIFIED_FUTURE.exception, timeout=0)
self.assertTrue(isinstance(EXCEPTION_FUTURE.exception(timeout=0),
OSError))
self.assertEqual(SUCCESSFUL_FUTURE.exception(timeout=0), None)
def test_exception_with_success(self):
def notification():
# Wait until the main thread is waiting for the exception.
time.sleep(1)
with f1._condition:
f1._state = FINISHED
f1._exception = OSError()
f1._condition.notify_all()
f1 = create_future(state=PENDING)
t = threading.Thread(target=notification)
t.start()
self.assertTrue(isinstance(f1.exception(timeout=support.SHORT_TIMEOUT), OSError))
t.join()
def test_multiple_set_result(self):
f = create_future(state=PENDING)
f.set_result(1)
with self.assertRaisesRegex(
futures.InvalidStateError,
'FINISHED: <Future at 0x[0-9a-f]+ '
'state=finished returned int>'
):
f.set_result(2)
self.assertTrue(f.done())
self.assertEqual(f.result(), 1)
def test_multiple_set_exception(self):
f = create_future(state=PENDING)
e = ValueError()
f.set_exception(e)
with self.assertRaisesRegex(
futures.InvalidStateError,
'FINISHED: <Future at 0x[0-9a-f]+ '
'state=finished raised ValueError>'
):
f.set_exception(Exception())
self.assertEqual(f.exception(), e)
def setUpModule():
setup_module()
if __name__ == "__main__":
unittest.main()
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