def parse_ordinal_identifier(ordinal_identifier, lineno=None):
"""Checks if the string `ordinal_identifier` is a number followed by one of
the suffixes st, nd, rd or th. Raises
chef.validators.OrdinalIdentifierError if it does not. Else, return the
appertaining number as an integer.
"""
m = re.match(ORDINAL_IDENTIFIER_PATTERN, ordinal_identifier)
if m is None:
raise syntax_errors.OrdinalIdentifierError(ordinal_identifier, lineno)
num_str, suffix = m.groups()
validate_ordinal_id_suffix(num_str, suffix, lineno)
return int(num_str)
def test_th(self, number):
with pytest.raises(syntax_errors.NonMatchingSuffixError) as e:
validate_ordinal_id_suffix(number, 'th')
# muahaha, side effects!
assert e.value.number == self.th_numbers.pop()
assert e.value.suffix == 'th'
