test_palindrome_checker.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Test module for palindrome_checker function.

Test categories:
    - Standard cases: typical palindromes and non-palindromes
    - Edge cases: empty strings, single characters, mixed-case strings
    - Defensive tests: wrong input types, assertions

Created on 2/1/2025
@author: Caesar Ghazi
"""

import unittest
from ..palindrome_checker import palindrome_checker


class TestPalindromeChecker(unittest.TestCase):
    """Test if the function correctly identifies palindromes."""

    # Standard test cases
    def test_simple_palindrome(self):
        """it should return True for a palindrome."""
        actual = palindrome_checker("racecar")
        expected = True
        self.assertEqual(actual, expected)

    def test_non_palindrome(self):
        """it should return False for a non-palindrome string."""
        actual = palindrome_checker("hello")
        expected = False
        self.assertEqual(actual, expected)

    def test_mixed_case_palindrome(self):
        """it should return True for palindromes for capital letters too."""
        actual = palindrome_checker("RaceCar")
        expected = True
        self.assertEqual(actual, expected)

    def test_palindrome_with_punctuation(self):
        """it should return True and ignore spaces and punctuation."""
        actual = palindrome_checker("No lemon, no melon")
        expected = True
        self.assertEqual(actual, expected)

    # Edge cases
    def test_empty_string(self):
        """it should return True for an empty string."""
        actual = palindrome_checker("")
        expected = True
        self.assertEqual(actual, expected)

    def test_single_character(self):
        """it should return True for a single character."""
        actual = palindrome_checker("a")
        expected = True
        self.assertEqual(actual, expected)

    def test_palindrome_with_numbers(self):
        """it should handle numeric palindromes correctly."""
        actual = palindrome_checker("12321")
        expected = True
        self.assertEqual(actual, expected)

    # Defensive Tests
    def test_invalid_text_type(self):
        """it should raise an AssertionError if the text parameter is not a string."""
        with self.assertRaises(AssertionError):
            palindrome_checker(12345)


if __name__ == "__main__":
    unittest.main()