def _multiprocessing_raise_processerror(arg):
try:
raise util.ProcessError(["a"], 1, "aa", "bb")
except BaseException as exc:
# If the following is just 'raise', multiprocessing will hang
# on Python 2.7.8 due to https://bugs.python.org/issue9400
raise util.ParallelFailure(str(exc), exc.__class__, traceback.format_exc())
def test_parallelfailure():
# Check the workaround for https://bugs.python.org/issue9400 works
if WIN and os.path.basename(sys.argv[0]).lower().startswith('py.test'):
# Multiprocessing in spawn mode can result to problems with py.test
pytest.skip("Multiprocessing spawn mode on Windows not safe to run "
"from py.test runner.")
# The exception class must be pickleable
exc = util.ParallelFailure("test", Exception, "something")
exc2 = pickle.loads(pickle.dumps(exc))
assert exc.message == exc2.message
assert exc.exc_cls == exc2.exc_cls
assert exc.traceback_str == exc2.traceback_str
assert str(exc) == "Exception: test\n something"
# Check multiprocessing does not hang (it would hang on Python
# 2.7.8 if the 'raise utill.ParallelFailure ...' above is changed
# to just 'raise')
pool = multiprocessing.Pool(4)
try:
pool.map(_multiprocessing_raise_processerror, range(10))
except util.ParallelFailure as exc:
pass
finally:
pool.close()
# Check reraising UserError
pool = multiprocessing.Pool(4)
try:
try:
pool.map(_multiprocessing_raise_usererror, range(10))
except util.ParallelFailure as exc:
exc.reraise()
finally:
pool.close()
assert False
except util.UserError as exc:
# OK
pass
def _multiprocessing_raise_usererror(arg):
try:
raise util.UserError("hello")
except BaseException as exc:
raise util.ParallelFailure(str(exc), exc.__class__,
traceback.format_exc())
