def test_timestampwithtimezone(): ts = Timestamp(seconds=0, microseconds=0) tstz = TimestampWithTimezone(timestamp=ts, offset=0, negative_utc=False) attr.validate(tstz) assert tstz.negative_utc is False assert tstz.offset_bytes == b"+0000" tstz = TimestampWithTimezone(timestamp=ts, offset=10, negative_utc=False) attr.validate(tstz) assert tstz.offset_bytes == b"+0010" tstz = TimestampWithTimezone(timestamp=ts, offset=-10, negative_utc=False) attr.validate(tstz) assert tstz.offset_bytes == b"-0010" tstz = TimestampWithTimezone(timestamp=ts, offset=0, negative_utc=True) attr.validate(tstz) assert tstz.negative_utc is True assert tstz.offset_bytes == b"-0000" > tstz = TimestampWithTimezone(timestamp=ts, offset=-630, negative_utc=True) .tox/py3-full/lib/python3.7/site-packages/swh/model/tests/test_model.py:471: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ <attrs generated init swh.model.model.TimestampWithTimezone>:13: in __init__ __attr_validator_negative_utc(self, __attr_negative_utc, self.negative_utc) .tox/py3-full/lib/python3.7/site-packages/attr/_make.py:3096: in __call__ v(inst, attr, value) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ self = TimestampWithTimezone(timestamp=Timestamp(seconds=0, microseconds=0), offset=-630, negative_utc=True, offset_bytes=b'-1030') attribute = Attribute(name='negative_utc', default=NOTHING, validator=_AndValidator(_validators=(<function type_validator.<locals>...=True, metadata=mappingproxy({}), type=<class 'bool'>, converter=None, kw_only=False, inherited=False, on_setattr=None) value = True @negative_utc.validator def check_negative_utc(self, attribute, value): if self.offset and value: > raise ValueError("negative_utc can only be True is offset=0") E ValueError: negative_utc can only be True is offset=0 .tox/py3-full/lib/python3.7/site-packages/swh/model/model.py:414: ValueError