94 lines
3.1 KiB
Python
94 lines
3.1 KiB
Python
"""
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ⒸAngelaMos | 2026
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test_cipher.py
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"""
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import pytest
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from caesar_cipher.cipher import CaesarCipher
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class TestCaesarCipher:
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def test_encrypt_basic(self) -> None:
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cipher = CaesarCipher(key = 3)
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assert cipher.encrypt("HELLO") == "KHOOR"
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def test_encrypt_lowercase(self) -> None:
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cipher = CaesarCipher(key = 3)
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assert cipher.encrypt("hello") == "khoor"
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def test_encrypt_mixed_case(self) -> None:
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cipher = CaesarCipher(key = 3)
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assert cipher.encrypt("Hello World") == "Khoor Zruog"
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def test_encrypt_preserves_spaces(self) -> None:
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cipher = CaesarCipher(key = 5)
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assert cipher.encrypt("ABC XYZ") == "FGH CDE"
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def test_encrypt_preserves_punctuation(self) -> None:
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cipher = CaesarCipher(key = 3)
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assert cipher.encrypt("Hello, World!") == "Khoor, Zruog!"
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def test_encrypt_preserves_numbers(self) -> None:
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cipher = CaesarCipher(key = 3)
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assert cipher.encrypt("Test123") == "Whvw123"
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def test_decrypt_basic(self) -> None:
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cipher = CaesarCipher(key = 3)
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assert cipher.decrypt("KHOOR") == "HELLO"
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def test_decrypt_lowercase(self) -> None:
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cipher = CaesarCipher(key = 3)
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assert cipher.decrypt("khoor") == "hello"
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def test_encrypt_decrypt_roundtrip(self) -> None:
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cipher = CaesarCipher(key = 13)
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original = "The Quick Brown Fox Jumps Over The Lazy Dog!"
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encrypted = cipher.encrypt(original)
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decrypted = cipher.decrypt(encrypted)
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assert decrypted == original
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def test_key_wrapping(self) -> None:
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cipher = CaesarCipher(key = 26)
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assert cipher.encrypt("ABC") == "ABC"
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def test_negative_key(self) -> None:
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cipher = CaesarCipher(key = -3)
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assert cipher.encrypt("HELLO") == "EBIIL"
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def test_zero_key(self) -> None:
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cipher = CaesarCipher(key = 0)
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assert cipher.encrypt("HELLO") == "HELLO"
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def test_key_validation_too_large(self) -> None:
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with pytest.raises(ValueError, match = "Key must be between -25 and 26"):
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CaesarCipher(key = 30)
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def test_key_validation_too_small(self) -> None:
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with pytest.raises(ValueError, match = "Key must be between -25 and 26"):
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CaesarCipher(key = -30)
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def test_crack_returns_all_shifts(self) -> None:
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results = CaesarCipher.crack("KHOOR")
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assert len(results) == 26
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def test_crack_finds_correct_shift(self) -> None:
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cipher = CaesarCipher(key = 3)
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encrypted = cipher.encrypt("HELLO")
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results = CaesarCipher.crack(encrypted)
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shifts_dict = dict(results)
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assert shifts_dict[3] == "HELLO"
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def test_empty_string(self) -> None:
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cipher = CaesarCipher(key = 3)
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assert cipher.encrypt("") == ""
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assert cipher.decrypt("") == ""
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def test_alphabet_wraparound_uppercase(self) -> None:
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cipher = CaesarCipher(key = 3)
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assert cipher.encrypt("XYZ") == "ABC"
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def test_alphabet_wraparound_lowercase(self) -> None:
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cipher = CaesarCipher(key = 3)
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assert cipher.encrypt("xyz") == "abc"
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