Many tests done, still more to come.

[szyfrow.git] / tests / test_cadenus.py

diff --git a/tests/test_cadenus.py b/tests/test_cadenus.py
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+++ b/tests/test_cadenus.py
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+import pytest
+import string 
+
+from szyfrow.cadenus import *
+from szyfrow.support.utilities import *
+
+def test_keycolumn():
+    assert make_cadenus_keycolumn()['a'] == 0
+    assert make_cadenus_keycolumn()['b'] == 1
+    assert make_cadenus_keycolumn()['c'] == 2
+    assert make_cadenus_keycolumn()['v'] == 21
+    assert make_cadenus_keycolumn()['w'] == 21
+    assert make_cadenus_keycolumn()['z'] == 24
+    assert make_cadenus_keycolumn(doubled_letters='ij', start='b', 
+        reverse=True)['a'] == 1
+    assert make_cadenus_keycolumn(doubled_letters='ij', start='b', 
+        reverse=True)['b'] == 0
+    assert make_cadenus_keycolumn(doubled_letters='ij', start='b', 
+        reverse=True)['c'] == 24
+    assert make_cadenus_keycolumn(doubled_letters='ij', start='b', 
+        reverse=True)['i'] == 18
+    assert make_cadenus_keycolumn(doubled_letters='ij', start='b', 
+        reverse=True)['j'] == 18
+    assert make_cadenus_keycolumn(doubled_letters='ij', start='b', 
+        reverse=True)['v'] == 6
+    assert make_cadenus_keycolumn(doubled_letters='ij', start='b', 
+        reverse=True)['z'] == 2
+
+
+def test_encipher_message():
+    plaintext = sanitise('''Whoever has made a voyage up the Hudson must 
+        remember the Kaatskill mountains. They are a dismembered branch of 
+        the great''')
+    keycol = make_cadenus_keycolumn(doubled_letters='vw', start='a', reverse=True)
+    ciphertext = cadenus_encipher(plaintext, 'wink', keycol)
+    expected = 'antodeleeeuhrsidrbhmhdrrhnimefmthgeaetakseomehetyaasuvoyegrastmmuuaeenabbtpchehtarorikswosmvaleatned'
+    assert ciphertext == expected
+
+    plaintext = sanitise('''a severe limitation on the usefulness of the 
+        cadenus is that every message must be a multiple of twenty-five 
+        letters long''')
+    ciphertext = cadenus_encipher(plaintext, 'easy', keycol)
+    expected = 'systretomtattlusoatleeesfiyheasdfnmschbhneuvsnpmtofarenuseieeieltarlmentieetogevesitfaisltngeeuvowul'
+    assert ciphertext == expected
+
+
+def test_decipher_message():
+    plaintext = sanitise('''Whoever has made a voyage up the Hudson must 
+        remember the Kaatskill mountains. They are a dismembered branch of 
+        the great''')
+    keycol = make_cadenus_keycolumn(doubled_letters='vw', start='a', reverse=True)
+    for key in ['wink', 'easy']: 
+        enciphered = cadenus_encipher(plaintext, key, keycol)
+        deciphered = cadenus_decipher(enciphered, key, keycol)
+        assert deciphered == plaintext
+
+
+def test_cadenus_break():
+    plaintext = sanitise('''It is a truth universally acknowledged, that a single man in
+             possession of a good fortune, must be in want of a wife. However
+             little known the feelings or views of such a man may be on his 
+             first entering a neighbourhood, this truth is so well fixed in
+             the minds of the surrounding families, that he is considered the
+             rightful property of some one or other of their daughters.''')
+    expected_key = 'swashbuckling'
+    expected_score = Ptrigrams(plaintext)
+    expected_keycol = make_cadenus_keycolumn(doubled_letters='vw', start='a', 
+        reverse=True)
+
+    ciphertext = cadenus_encipher(plaintext, expected_key, expected_keycol)
+    
+    # dictionary = ['clearinghouse', 'computerising', 'counterclaims', 
+    #     'housewarmings',  'intravenously', 'liquefactions', 'somersaulting', 
+    #     'sportsmanlike', 'swashbuckling']
+
+    dictionary = ['swashbuckling']
+
+    (key, keycol), score = cadenus_break(ciphertext, words=dictionary, 
+        fitness=Ptrigrams)
+
+    assert key == expected_key
+    assert keycol == expected_keycol
+    assert score == pytest.approx(expected_score)