def test_passes_with_generated_card_numbers():
# cards generated from http://www.getcreditcardnumbers.com/
card_numbers = [
# Visa
"4393638352371292",
"4061357847532811",
"4929788549317527",
# Am Ex
"373941476764901",
"344132697731657",
"345959434906872",
# Master Card
"5555555555554444",
"5278728158565051",
"5530905498002995",
# Discover
"6011111111111117",
"6011058150190850",
"6011590615964099",
]
for card_num in card_numbers:
assert luhn_check(card_num) is True
for digit in string.digits:
if digit != card_num[-1:]:
# assert every other value for the check digit fails
assert luhn_check(f"{card_num[:-1]}{digit}") is False
def is_valid(self):
'''
Uses the Luhn algorithm and card number length to determine validity
Does not guarantee the card number is in use
'''
return (
MIN_LENGTH <= len(self._number) <= MAX_LENGTH
and luhn_check(self.value)
)
def test_requires_digit_input():
with pytest.raises(ValueError):
luhn_check("ff0000")
with pytest.raises(ValueError):
luhn_check("four five")
with pytest.raises(ValueError):
luhn_check("")
with pytest.raises(ValueError):
luhn_check("----")
def test_strips_filler_characters():
assert luhn_check(" 4111 1111 1111 1111 ") is True
assert luhn_check("4111-1111-1111-1111") is True
assert luhn_check("4111.1111.1111.1111") is True
assert luhn_check("4111|1111|1111|1111") is True
assert luhn_check("4111:1111:1111:1111") is True
assert luhn_check(".-: 4111 | 1111 | 1111 | 1111 :-.") is True
assert luhn_check("4111 1111 1111 1114") is False
def test_requires_string_input():
with pytest.raises(TypeError):
luhn_check(4111111111111111)
with pytest.raises(TypeError):
luhn_check(None)
def test_fails_with_incorrect_check_digit():
assert luhn_check("4111111111111110") is False
assert luhn_check("4111111111111112") is False
assert luhn_check("4111111111111113") is False
assert luhn_check("4111111111111114") is False
assert luhn_check("4111111111111115") is False
assert luhn_check("4111111111111116") is False
assert luhn_check("4111111111111117") is False
assert luhn_check("4111111111111118") is False
assert luhn_check("4111111111111119") is False
assert luhn_check("4444444444444440") is False
assert luhn_check("4444444444444441") is False
assert luhn_check("4444444444444442") is False
assert luhn_check("4444444444444443") is False
assert luhn_check("4444444444444444") is False
assert luhn_check("4444444444444445") is False
assert luhn_check("4444444444444446") is False
assert luhn_check("4444444444444447") is False
assert luhn_check("4444444444444449") is False
def test_passes_common_fakes():
assert luhn_check("4111111111111111") is True
assert luhn_check("4444444444444448") is True