Unit Testing with unittest

advanced level · ~20 min · Module 19: Testing & Quality Assurance

Verify code correctness automatically with TestCase assertions.

Learning objectives

Create test classes inheriting from unittest.TestCase
Use self.assertEqual, self.assertTrue, self.assertRaises

Lesson material

Testing Protocol

Unit tests test individual isolated functions or methods.

Example code

import unittest

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

class TestMath(unittest.TestCase):
    def test_add(self):
        self.assertEqual(add(2, 3), 5)
        self.assertEqual(add(-1, 1), 0)

suite = unittest.TestLoader().loadTestsFromTestCase(TestMath)
runner = unittest.TextTestRunner(verbosity=0)
res = runner.run(suite)
print("Tests Passed:", res.wasSuccessful())

Practice exercise: Write a Test Case

Write a unittest test case testing a function `is_even(n)` returning `True` for `4` and `False` for `5`.

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