tests/test_column_transposition.py

   1 import pytest
   2 import string
   3
   4 from szyfrow.column_transposition import *
   5 from szyfrow.support.utilities import *
   6
   7 def test_encipher_message():
   8     ciphertext =  column_transposition_encipher('hellothere', 'abcdef', fillcolumnwise=True)
   9     assert ciphertext == 'hlohr eltee '
  10     ciphertext =  column_transposition_encipher('hellothere', 'abcdef', fillcolumnwise=True, emptycolumnwise=True)
  11     assert ciphertext == 'hellothere  '
  12     ciphertext =  column_transposition_encipher('hellothere', 'abcdef')
  13     assert ciphertext == 'hellothere  '
  14     ciphertext =  column_transposition_encipher('hellothere', 'abcde')
  15     assert ciphertext == 'hellothere'
  16     ciphertext =  column_transposition_encipher('hellothere', 'abcde', fillcolumnwise=True, emptycolumnwise=True)
  17     assert ciphertext == 'hellothere'
  18     ciphertext =  column_transposition_encipher('hellothere', 'abcde', fillcolumnwise=True, emptycolumnwise=False)
  19     assert ciphertext == 'hlohreltee'
  20     ciphertext =  column_transposition_encipher('hellothere', 'abcde', fillcolumnwise=False, emptycolumnwise=True)
  21     assert ciphertext == 'htehlelroe'
  22     ciphertext =  column_transposition_encipher('hellothere', 'abcde', fillcolumnwise=False, emptycolumnwise=False)
  23     assert ciphertext == 'hellothere'
  24     ciphertext =  column_transposition_encipher('hellothere', 'clever', fillcolumnwise=True, emptycolumnwise=True)
  25     assert ciphertext == 'heotllrehe'
  26     ciphertext =  column_transposition_encipher('hellothere', 'clever', fillcolumnwise=True, emptycolumnwise=False)
  27     assert ciphertext == 'holrhetlee'
  28     ciphertext =  column_transposition_encipher('hellothere', 'clever', fillcolumnwise=False, emptycolumnwise=True)
  29     assert ciphertext == 'htleehoelr'
  30     ciphertext =  column_transposition_encipher('hellothere', 'clever', fillcolumnwise=False, emptycolumnwise=False)
  31     assert ciphertext == 'hleolteher'
  32     ciphertext =  column_transposition_encipher('hellothere', 'cleverly')
  33     assert ciphertext == 'hleolthre e '
  34     ciphertext =  column_transposition_encipher('hellothere', 'cleverly', fillvalue='!')
  35     assert ciphertext == 'hleolthre!e!'
  36     ciphertext =  column_transposition_encipher('hellothere', 'cleverly', fillvalue=lambda: '*')
  37     assert ciphertext == 'hleolthre*e*'
  38
  39 def test_decipher_message():
  40     plaintext = 'hereissometexttoencipher'
  41     for key in ['bayes', 'samplekey']:
  42         for fillcolumnwise in [True, False]:
  43             for emptycolumnwise in [True, False]:
  44                 enciphered = column_transposition_encipher(plaintext, key,
  45                     fillcolumnwise=fillcolumnwise, emptycolumnwise=emptycolumnwise)
  46                 deciphered = column_transposition_decipher(enciphered, key,
  47                     fillcolumnwise=fillcolumnwise, emptycolumnwise=emptycolumnwise)
  48                 assert deciphered.strip() == plaintext
  49
  50
  51 def test_encipher_scytale():
  52     assert scytale_encipher('thequickbrownfox', 3) == 'tcnhkfeboqrxuo iw '
  53     assert scytale_encipher('thequickbrownfox', 4) == 'tubnhirfecooqkwx'
  54     assert scytale_encipher('thequickbrownfox', 5) == 'tubn hirf ecoo qkwx '
  55     assert scytale_encipher('thequickbrownfox', 6) == 'tqcrnxhukof eibwo '
  56     assert scytale_encipher('thequickbrownfox', 7) == 'tqcrnx hukof  eibwo  '
  57
  58 def test_decipher_scytale():
  59     plaintext = 'hereissometexttoencipher'
  60     for key in range(3, 8):
  61         enciphered = scytale_encipher(plaintext, key)
  62         deciphered = scytale_decipher(enciphered, key)
  63         assert deciphered.strip() == plaintext
  64
  65 def test_column_transposition_break():
  66     plaintext = sanitise('''It is a truth universally acknowledged, that a single man in
  67              possession of a good fortune, must be in want of a wife. However
  68              little known the feelings or views of such a man may be on his
  69              first entering a neighbourhood, this truth is so well fixed in
  70              the minds of the surrounding families, that he is considered the
  71              rightful property of some one or other of their daughters.''')
  72     expected_key = 'encipher'
  73     expected_fill = False
  74     expected_empty = True
  75     expected_score = Pbigrams(plaintext)
  76     ciphertext = column_transposition_encipher(plaintext, expected_key,
  77         fillcolumnwise=expected_fill, emptycolumnwise=expected_empty)
  78     used_translist = collections.defaultdict(list)
  79     for word in 'encipher fourteen keyword'.split():
  80         used_translist[transpositions_of(word)] += [word]
  81
  82     (key, fill, empty), score = column_transposition_break_mp(ciphertext,
  83         translist=used_translist)
  84
  85     assert key == transpositions_of(expected_key)
  86     assert fill == expected_fill
  87     assert empty == expected_empty
  88     assert score == pytest.approx(expected_score)
  89
  90 def test_scytale_break():
  91     plaintext = sanitise('''It is a truth universally acknowledged, that a single man in
  92              possession of a good fortune, must be in want of a wife. However
  93              little known the feelings or views of such a man may be on his
  94              first entering a neighbourhood, this truth is so well fixed in
  95              the minds of the surrounding families, that he is considered the
  96              rightful property of some one or other of their daughters.''')
  97     expected_key = 5
  98     expected_score = Pbigrams(plaintext)
  99     ciphertext = scytale_encipher(plaintext, expected_key)
 100
 101     key, score = scytale_break_mp(ciphertext)
 102
 103     assert key == expected_key
 104     assert score == pytest.approx(expected_score)
 105