unit test failing for test_main.py::test_request_flow_list

[italovalcy]

Hi,

The last daily execution pointed out the following failure:

============================= test session starts ==============================
platform linux -- Python 3.9.13, pytest-7.0.0, pluggy-0.13.1
cachedir: .tox/py39/.pytest_cache
rootdir: /builds/kytos/of_core/of_core, configfile: pytest.ini
plugins: cov-3.0.0, asyncio-0.18.3
asyncio: mode=auto
collected 99 items

tests/unit/test_action.py ......                                         [  6%]
tests/unit/test_flow.py ...........                                      [ 17%]
tests/unit/test_main.py .......................F.....                    [ 46%]
tests/unit/test_match.py ....                                            [ 50%]
tests/unit/test_msg_prios.py .........................                   [ 75%]
tests/unit/test_utils.py ..........                                      [ 85%]
tests/unit/v0x01/test_utils.py .......                                   [ 92%]
tests/unit/v0x04/test_utils.py .......                                   [100%]

=================================== FAILURES ===================================
_______________________ TestMain.test_request_flow_list ________________________

self = <of_core.tests.unit.test_main.TestMain testMethod=test_request_flow_list>
args = (<MagicMock name='update_flow_list' id='140403813278480'>, <MagicMock name='update_flow_list' id='140403813147168'>, <...cMock name='_check_overlapping_multipart_request' id='140403813201328'>, <MagicMock name='sleep' id='140403813316352'>)
mock_update_flow_list_v0x01 = <MagicMock name='update_flow_list' id='140403813278480'>
mock_update_flow_list_v0x04 = <MagicMock name='update_flow_list' id='140403813147168'>
mock_check_overlapping_multipart_request = <MagicMock name='_check_overlapping_multipart_request' id='140403813201328'>

    @patch('time.sleep', return_value=None)
    @patch('napps.kytos.of_core.main.Main.'
           '_check_overlapping_multipart_request')
    @patch('napps.kytos.of_core.v0x04.utils.update_flow_list')
    @patch('napps.kytos.of_core.v0x01.utils.update_flow_list')
    def test_request_flow_list(self, *args):
        """Test request flow list."""
        (mock_update_flow_list_v0x01, mock_update_flow_list_v0x04,
         mock_check_overlapping_multipart_request, _) = args
        mock_update_flow_list_v0x04.return_value = 0xABC
        mock_check_overlapping_multipart_request.return_value = False
        self.napp._request_flow_list(self.switch_v0x01)
        mock_update_flow_list_v0x01.assert_called_with(self.napp.controller,
                                                       self.switch_v0x01)
        self.napp._request_flow_list(self.switch_v0x04)
>       mock_update_flow_list_v0x04.assert_called_with(self.napp.controller,
                                                       self.switch_v0x04)

tests/unit/test_main.py:432: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

self = <MagicMock name='update_flow_list' id='140403813147168'>
args = (<kytos.core.controller.Controller object at 0x7fb254068c70>, <MagicMock name='mock.switch' spec='Switch' id='140403811019792'>)
kwargs = {}
expected = "update_flow_list(<kytos.core.controller.Controller object at 0x7fb254068c70>, <MagicMock name='mock.switch' spec='Switch' id='140403811019792'>)"
actual = 'not called.'
error_message = "expected call not found.\nExpected: update_flow_list(<kytos.core.controller.Controller object at 0x7fb254068c70>, <MagicMock name='mock.switch' spec='Switch' id='140403811019792'>)\nActual: not called."

    def assert_called_with(self, /, *args, **kwargs):
        """assert that the last call was made with the specified arguments.

        Raises an AssertionError if the args and keyword args passed in are
        different to the last call to the mock."""
        if self.call_args is None:
            expected = self._format_mock_call_signature(args, kwargs)
            actual = 'not called.'
            error_message = ('expected call not found.\nExpected: %s\nActual: %s'
                    % (expected, actual))
>           raise AssertionError(error_message)
E           AssertionError: expected call not found.
E           Expected: update_flow_list(<kytos.core.controller.Controller object at 0x7fb254068c70>, <MagicMock name='mock.switch' spec='Switch' id='140403811019792'>)
E           Actual: not called.

Running the same pipeline again returns success; if we keep repeating the tests, we eventually get the same error again.

I've already noticed that the test method that runs in a thread (i.e., using the run_on_thread or listen_to decorators) actually gives certain uncertainty. So maybe that is the cause.

[viniarck]

Good catch @italovalcy, thanks for reporting this.