test_cipher.py

import pytest
import caesar
import affine
import vigenere

def test_caesar_encrypt_decrypt():
    plaintext = "hello world!!"
    key = 3
    encrypted = caesar.caesarEncrypt(plaintext, key)
    decrypted = caesar.caesarDecrypt(encrypted, key)
    assert decrypted == plaintext

def test_caesar_encrypt_lowercase():
    assert caesar.caesarEncrypt("abc", 1) == "bcd"

def test_caesar_encrypt_uppercase():
    assert caesar.caesarEncrypt("XYZ", 2) == "ZAB"

def test_caesar_encrypt_numbers():
    assert caesar.caesarEncrypt("123", 5) == "123"

def test_caesar_encrypt_special_characters():
    assert caesar.caesarEncrypt("!#€%&/()=?", 5) == "!#€%&/()=?"

def test_affine_encrypt_decrypt():
    plaintext = "hello world"
    a, b = 5, 8
    encrypted = affine.affineEncrypt(plaintext, a, b)
    decrypted = affine.affineDecrypt(encrypted, a, b)
    assert decrypted == plaintext

def test_affine_encrypt_uppercase():
    assert affine.affineEncrypt("ABC", 3, 7) == "HKN"

def test_affine_encrypt_numbers():
    assert affine.affineEncrypt("123", 5, 8) == "123"

def test_affine_encrypt_special_characters():
    assert affine.affineEncrypt("!#€%&/()=?", 5, 8) == "!#€%&/()=?"

def test_affine_invalid_key():
    with pytest.raises(ValueError):
        affine.affineEncrypt("test", 2, 5)  # 2 is not coprime with 26

def test_affine_decrypt_invalid_key():
    with pytest.raises(ValueError):
        affine.affineDecrypt("test", 2, 5)  # 2 is not coprime with 26


def test_vigenere_encrypt_decrypt():
    plaintext = "HELLOWORLD"
    key = "ee"
    encrypted = vigenere.vigenereEncrypt(plaintext, key)
    decrypted = vigenere.vigenereDecrypt(encrypted, key)
    assert decrypted == plaintext

def test_vigenere_encrypt_lowercase():
    plaintext = "abc"
    key = "ee"
    assert vigenere.vigenereEncrypt(plaintext, key) == "efg"

def test_vigenere_encrypt_uppercase():
    plaintext = "XYZ"
    key = "bra"
    assert vigenere.vigenereEncrypt(plaintext, key) == "YPZ"

def test_vigenere_encrypt_numbers():
    plaintext = "123"
    key = "aa"
    assert vigenere.vigenereEncrypt(plaintext, key) == "123"

def test_vigenere_encrypt_special_characters():
    plaintext = "!#€%&/()=?"
    key = "ae"
    assert vigenere.vigenereEncrypt(plaintext, key) == "!#€%&/()=?"