update check_palindromes

solutions/check_palindromes.py

@@ -35,15 +35,15 @@ def check_palindromes(words_to_check: List[str]) -> None:
     'Test' is not a palindrome.
 
     """
+    if not isinstance(words_to_check, list):
+        raise TypeError("Input must be a list")
+
     for value in words_to_check:
+        if not isinstance(value, str):
+            raise TypeError("List must contain only strings")
         cleaned_value = "".join(filter(str.isalnum, value)).lower()
 
         if cleaned_value == cleaned_value[::-1]:
             print(f"'{value}' is a palindrome.")
         else:
             print(f"'{value}' is not a palindrome.")
-
-
-if __name__ == "__main__":
-    words_to_check_list = ["Radar", "12321", "Hello", "1.232.1", "12345", "aA", "Test"]
-    check_palindromes(words_to_check_list)

solutions/tests/test_check_palindromes.py

@@ -1,51 +1,71 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
 """
-Module represents unit test for check_palindromes
+Unit test module for checking palindromes.
 
-Created on 01/11/2025
-Author fevziismailsahin
+Test categories:
+    - Standard cases: correct inputs for words and numbers;
+    - Edge cases;
+    - Defensive tests: wrong input types, assertions;
+
+Author: fevziismailsahin
+Created: 01/11/2025
 """
 
+import sys
 import unittest
+from io import StringIO
+
+from ..check_palindromes import check_palindromes
+
+
+class TestCheckPalindromes(unittest.TestCase):
+    """Test suite for checking palindromes."""
+
+    def setUp(self):
+        """Set up the test environment."""
+        self.held_output = StringIO()
+        sys.stdout = self.held_output
+
+    def tearDown(self):
+        """Tear down the test environment."""
+        sys.stdout = sys.__stdout__
+
+    # Standard cases: correct inputs
+    def test_standard_case_1(self):
+        """Test with typical valid inputs for words and numbers."""
+        check_palindromes(["Radar", "12321", "Hello", "1.232.1", "12345", "aA", "Test"])
+        self.assertIn("'Radar' is a palindrome.", self.held_output.getvalue())
+        self.assertIn("'12321' is a palindrome.", self.held_output.getvalue())
+        self.assertIn("'Hello' is not a palindrome.", self.held_output.getvalue())
+        self.assertIn("'1.232.1' is a palindrome.", self.held_output.getvalue())
+        self.assertIn("'12345' is not a palindrome.", self.held_output.getvalue())
+        self.assertIn("'aA' is a palindrome.", self.held_output.getvalue())
+        self.assertIn("'Test' is not a palindrome.", self.held_output.getvalue())
+
+    # Edge cases: testing empty and single-character strings
+    def test_empty_string(self):
+        """Test with an empty string."""
+        check_palindromes([""])
+        self.assertIn("'' is a palindrome.", self.held_output.getvalue())
+
+    def test_single_character(self):
+        """Test with a single character."""
+        check_palindromes(["a", "1", "!"])
+        self.assertIn("'a' is a palindrome.", self.held_output.getvalue())
+        self.assertIn("'1' is a palindrome.", self.held_output.getvalue())
+        self.assertIn("'!' is a palindrome.", self.held_output.getvalue())
+
+    # Defensive tests: wrong input types, assertions
+    def test_invalid_input_type(self):
+        """Test when input is not a list."""
+        with self.assertRaises(TypeError):
+            check_palindromes("not a list")
 
-from solutions.check_palindromes import check_palindromes
-
-
-class TestPalindromeChecker(unittest.TestCase):
-    def test_palindrome_words(self):
-        """
-        Test: Check palindrome words correctly identified.
-        """
-        with self.assertLogs(level="INFO") as log:
-            check_palindromes(["Radar", "12321", "aA"])
-            self.assertIn("'Radar' is a palindrome.", log.output)
-            self.assertIn("'12321' is a palindrome.", log.output)
-            self.assertIn("'aA' is a palindrome.", log.output)
-
-    def test_non_palindrome_words(self):
-        """
-        Test: Check non-palindrome words correctly identified.
-        """
-        with self.assertLogs(level="INFO") as log:
-            check_palindromes(["Hello", "12345", "Test"])
-            self.assertIn("'Hello' is not a palindrome.", log.output)
-            self.assertIn("'12345' is not a palindrome.", log.output)
-            self.assertIn("'Test' is not a palindrome.", log.output)
-
-    def test_mixed_case(self):
-        """
-        Test: Check case-insensitive palindrome detection.
-        """
-        with self.assertLogs(level="INFO") as log:
-            check_palindromes(["aA"])
-            self.assertIn("'aA' is a palindrome.", log.output)
-
-    def test_special_characters(self):
-        """
-        Test: Check if special characters are correctly removed and palindrome check works.
-        """
-        with self.assertLogs(level="INFO") as log:
-            check_palindromes(["1.232.1"])
-            self.assertIn("'1.232.1' is a palindrome.", log.output)
+    def test_non_string_elements(self):
+        """Test when input list contains non-string elements."""
+        with self.assertRaises(TypeError):
+            check_palindromes([123, 456])
 
 
 if __name__ == "__main__":