def test_done_callback_with_cancel(self):
was_cancelled = [None]
def fn(callback_future):
was_cancelled[0] = callback_future.cancelled()
f = Future()
f.add_done_callback(fn)
assert f.cancel()
assert was_cancelled[0]
def test_done_callback_already_successful(self):
callback_result = [None]
def fn(callback_future):
callback_result[0] = callback_future.result()
f = Future()
f.set_result(5)
f.add_done_callback(fn)
assert 5 == callback_result[0]
def test_done_callback_with_exception(self):
callback_exception = [None]
def fn(callback_future):
callback_exception[0] = callback_future.exception()
f = Future()
f.add_done_callback(fn)
f.set_exception(Exception('test'))
assert ('test', ) == callback_exception[0].args
def test_done_callback_with_result(self):
callback_result = [None]
def fn(callback_future):
callback_result[0] = callback_future.result()
f = Future()
f.add_done_callback(fn)
f.set_result(5)
assert 5 == callback_result[0]
def test_done_callback_raises(self):
# with captured_stderr() as stderr:
raising_was_called = [False]
fn_was_called = [False]
def raising_fn(callback_future):
raising_was_called[0] = True
raise Exception('doh!')
def fn(callback_future):
fn_was_called[0] = True
f = Future()
f.add_done_callback(raising_fn)
f.add_done_callback(fn)
f.set_result(5)
assert raising_was_called
assert fn_was_called
def test_done_callback_raises(self):
with captured_stderr() as stderr:
import logging
log = logging.getLogger("concurrent.futures")
log.addHandler(logging.StreamHandler())
raising_was_called = [False]
fn_was_called = [False]
def raising_fn(callback_future):
raising_was_called[0] = True
raise Exception('foobar')
def fn(callback_future):
fn_was_called[0] = True
f = Future()
f.add_done_callback(raising_fn)
f.add_done_callback(fn)
f.set_result(5)
assert raising_was_called[0]
assert fn_was_called[0]
assert 'Exception: foobar' in stderr.getvalue()
del log.handlers[:]
def create_future(state=PENDING, exception=None, result=None):
f = Future()
f._state = state
f._exception = exception
f._result = result
return f
