def test_can_fail_a_conversion_that_potentially_returns_failure(self):
assert_that(
validate(
conversion_of(
'language', 'xx',
StringToObjectParser(lambda lang_string: Failure(
message='uh oh')))).map(lambda p: p.language),
equal_to(Failure(message='uh oh')))
def test_or_fail_with_replaces_failure(self):
result = Failure(message='Fail').or_fail_with(value=0)
assert result.value == 0
def test_do_on_failure_is_not_executed(self):
side_effect = SideEffect()
result = Failure(
message='Fail').do(lambda result: side_effect.execute())
assert not side_effect.executed
assert result.message == 'Fail'
def test_map_on_failure_returns_same_failure(self):
result = Failure(message='Fail').map(lambda r: Success(value=10))
assert result.message == 'Fail'
def test_fails_when_it_has_trailing_word_chars(self):
assert_that(int_from_string().parse_from("100W"),
equal_to(Failure(message="'100W' is not a valid integer")))
def test_returns_failure_is_date_is_not_present(self):
assert_that(date_from_iso.parse_from(None),
equal_to(Failure(message="date is missing")))
def test_returns_failure_is_date_is_not_an_iso_string(self):
assert_that(
date_from_iso.parse_from("2020-1008"),
equal_to(Failure(message="Invalid isoformat string: '2020-1008'")))
def test_returns_failure_when_value_is_not_present(self):
assert_that(
validate(presence_of('some_parameter',
None)).map(lambda p: p.some_parameter),
equal_to(Failure(message='some_parameter is missing')))