def test_odd_and_even_neither_validate_2_nor_5():
p = (odd & even).validates(
fmap(lambda xs: int(''.join(xs)), many1(character())))
with pytest.raises(ParsingFailed):
run_parser(p, '2')
with pytest.raises(ParsingFailed):
run_parser(p, '5')
def test_that_fmap_does_not_change_error_messages(runner):
parser = literal('a')
with pytest.raises(ParsingFailed) as error_message_without_fmap:
runner(parser, 'b')
with pytest.raises(ParsingFailed) as error_message_with_fmap:
runner(fmap(lambda char: char + 1, parser), 'b')
assert (
str(error_message_without_fmap.value) ==
str(error_message_with_fmap.value)
)
def test_even_validates_2():
p = even.validates(fmap(lambda xs: int(''.join(xs)), many1(character())))
assert run_parser(p, '2').value == 2
def test_odd_or_even_validates_2_and_5():
p = (odd | even).validates(
fmap(lambda xs: int(''.join(xs)), many1(character())))
assert run_parser(p, '2').value == 2
assert run_parser(p, '5').value == 5
def test_odd_does_validate_5():
p = odd.validates(fmap(lambda xs: int(''.join(xs)), many1(character())))
assert run_parser(p, '5').value == 5
def test_even_does_not_validate_5():
p = even.validates(fmap(lambda xs: int(''.join(xs)), many1(character())))
with pytest.raises(ParsingFailed):
run_parser(p, '3')
def test_fmap_can_map_1000_times(runner):
parser = literal('a')
for i in range(0, 1000):
parser = fmap(lambda x: 'b', parser)
assert runner(parser, 'a').value == 'b'
def test_fmap_can_replace_parsing_result(runner):
parser = fmap(
lambda x: 'b',
literal('a')
)
assert runner(parser, 'a').value == 'b'
