Test Classes & TestCase

Test Classes & TestCase

In unittest, tests are organized into classes that inherit from unittest.TestCase. Each test class groups related test methods together, making your test suite organized and readable.

Creating a Test Class

import unittest

class TestStringMethods(unittest.TestCase):
    def test_upper(self):
        self.assertEqual('hello'.upper(), 'HELLO')

    def test_isupper(self):
        self.assertTrue('HELLO'.isupper())
        self.assertFalse('Hello'.isupper())

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

Rules for Test Classes

• The class must inherit from unittest.TestCase.
• Class names should start with Test (e.g., TestLogin).
• The class must not have an __init__ method.
• Test methods inside must start with test_.

Multiple Test Classes

import unittest

class TestUserCreation(unittest.TestCase):
    def test_create_user(self):
        user = {"name": "Alice", "age": 30}
        self.assertIn("name", user)

class TestUserDeletion(unittest.TestCase):
    def test_delete_user(self):
        users = []
        users.append("Alice")
        users.remove("Alice")
        self.assertEqual(len(users), 0)

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

Key Takeaway

Every test must live inside a class that inherits from unittest.TestCase. This provides all the assertion methods and lifecycle hooks you need.