Many tests done, still more to come.

[szyfrow.git] / tests / test_bifid.py

diff --git a/tests/test_bifid.py b/tests/test_bifid.py
new file mode 100644 (file)
index 0000000..1077411
--- /dev/null
+++ b/tests/test_bifid.py
@@ -0,0 +1,57 @@
+import pytest
+import string 
+
+from szyfrow.bifid import *
+from szyfrow.support.utilities import *
+
+def test_grid():
+    trans, f_grid, r_grid = bifid_grid('bayes', KeywordWrapAlphabet.from_a, None)
+    assert len(f_grid) == 25
+    assert len(r_grid) == 25
+    for l in f_grid:
+        assert l == r_grid[f_grid[l]]
+    assert r_grid[1, 1] == 'b'
+    assert r_grid[2, 1] == 'c'
+
+
+def test_encipher_message():
+    assert bifid_encipher("indiajelly", 'iguana') == 'ibidonhprm'
+    assert bifid_encipher("indiacurry", 'iguana', period=4, fillvalue='x') == 'ibnhgaqltzml'
+    with pytest.raises(ValueError):
+        bifid_encipher("indiacurry", 'iguana', period=4)
+
+
+def test_decipher_message():
+    plaintext = 'hereissometexttoencipher'
+    for key in ['bayes', 'samplekey']:
+        enciphered = bifid_encipher(plaintext, key)
+        deciphered = bifid_decipher(enciphered, key)
+        assert deciphered == plaintext
+
+    for key in ['bayes', 'samplekey']:
+        enciphered = bifid_encipher(plaintext, key, period=5, fillvalue='a')
+        deciphered = bifid_decipher(enciphered, key, period=5, fillvalue='a')
+        assert deciphered == plaintext + pad(len(plaintext), 5, 'a') 
+
+
+def test_bifid_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 = 'encipher'
+    expected_wrap = KeywordWrapAlphabet.from_a
+    expected_period = 0
+    expected_score = Pletters(plaintext)
+    ciphertext = bifid_encipher(plaintext, expected_key, 
+        wrap_alphabet=expected_wrap)
+    
+    (key, wrap, period), score = bifid_break(ciphertext, 
+        wordlist='encipher fourteen keyword'.split())
+
+    assert key == expected_key
+    assert wrap == expected_wrap
+    assert period == expected_period
+    assert score == pytest.approx(expected_score)