What types of tests do you usually write to verify individual code components?

To test individual code components, the following types of tests are usually written:

• Unit tests: check the correctness of individual functions or methods in isolation.
• Integration tests: verify the interaction of multiple components together.

For unit tests in Python, frameworks like unittest or pytest are often used. Here's an example of a simple unit test:

import unittest

def add(a, b):
    return a + b

class TestAddFunction(unittest.TestCase):
    def test_add_positive_numbers(self):
        self.assertEqual(add(2, 3), 5)

    def test_add_negative_numbers(self):
        self.assertEqual(add(-1, -1), -2)

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

Unit tests help quickly identify errors at the level of individual components.