tahoe-lafs/src/allmydata/test/test_base62.py

67 lines
2.4 KiB
Python

import random, unittest
from allmydata.util import base62, mathutil
def insecurerandstr(n):
return ''.join(map(chr, map(random.randrange, [0]*n, [256]*n)))
class T(unittest.TestCase):
def _test_num_octets_that_encode_to_this_many_chars(self, chars, octets):
assert base62.num_octets_that_encode_to_this_many_chars(chars) == octets, "%s != %s <- %s" % (octets, base62.num_octets_that_encode_to_this_many_chars(chars), chars)
def _test_ende(self, bs):
ascii=base62.b2a(bs)
bs2=base62.a2b(ascii)
assert bs2 == bs, "bs2: %s:%s, bs: %s:%s, ascii: %s:%s" % (len(bs2), repr(bs2), len(bs), repr(bs), len(ascii), repr(ascii))
def test_num_octets_that_encode_to_this_many_chars(self):
return self._test_num_octets_that_encode_to_this_many_chars(2, 1)
return self._test_num_octets_that_encode_to_this_many_chars(3, 2)
return self._test_num_octets_that_encode_to_this_many_chars(5, 3)
return self._test_num_octets_that_encode_to_this_many_chars(6, 4)
def test_ende_0x00(self):
return self._test_ende('\x00')
def test_ende_0x01(self):
return self._test_ende('\x01')
def test_ende_0x0100(self):
return self._test_ende('\x01\x00')
def test_ende_0x000000(self):
return self._test_ende('\x00\x00\x00')
def test_ende_0x010000(self):
return self._test_ende('\x01\x00\x00')
def test_ende_randstr(self):
return self._test_ende(insecurerandstr(2**4))
def test_ende_longrandstr(self):
return self._test_ende(insecurerandstr(random.randrange(0, 2**10)))
def test_odd_sizes(self):
for j in range(2**6):
lib = random.randrange(1, 2**8)
numos = mathutil.div_ceil(lib, 8)
bs = insecurerandstr(numos)
# zero-out unused least-sig bits
if lib%8:
b=ord(bs[-1])
b = b >> (8 - (lib%8))
b = b << (8 - (lib%8))
bs = bs[:-1] + chr(b)
asl = base62.b2a_l(bs, lib)
assert len(asl) == base62.num_chars_that_this_many_octets_encode_to(numos) # the size of the base-62 encoding must be just right
bs2l = base62.a2b_l(asl, lib)
assert len(bs2l) == numos # the size of the result must be just right
assert bs == bs2l
def suite():
suite = unittest.makeSuite(T, 'test')
return suite
if __name__ == "__main__":
unittest.main()