Skip to content

✅ Module 09: Testing

Testing is how we gain confidence that code works now and still works after changes. This module focuses on practical testing skills using Python's built-in unittest library and the popular third-party framework pytest.

Estimated Time: 8-10 hours \ Prerequisites: Module 01 (Foundations), Module 05 (Functional Programming) \ Level: ⭐⭐⭐ Intermediate

📚 Topics Covered

# Topic Description Key Concepts
01 Why Testing What testing is and why it's valuable confidence, regression, fast feedback
02 Unit Testing Testing small units of logic arrange/act/assert, unittest, pytest
03 Test-Driven Development Writing tests before code red/green/refactor, small steps
04 Mocking Replacing slow/unreliable dependencies unittest.mock, stubs, fakes
05 Integration Testing Testing multiple components together boundaries, fixtures, test data

🎯 Learning Goals

By the end of this module, you should be able to:

  • Explain the difference between unit, integration, and end-to-end tests.
  • Write small, readable tests with clear assertions.
  • Use pytest basics (test functions, assertions, fixtures) and/or Python unittest.
  • Apply TDD to implement code in safe, incremental steps.
  • Use mocks for network/time/randomness/IO dependencies.

This repo does not require extra dependencies, but if you want to use pytest:

pip install pytest

📂 Module Structure

09_testing/
├── README.md
├── 01_why_testing/
│   ├── README.md
│   ├── examples.py
│   ├── exercises.py
│   └── quiz.md
├── 02_unit_testing/
│   ├── README.md
│   ├── examples.py
│   ├── exercises.py
│   └── quiz.md
├── 03_test_driven_development/
│   ├── README.md
│   ├── examples.py
│   ├── exercises.py
│   └── quiz.md
├── 04_mocking/
│   ├── README.md
│   ├── examples.py
│   ├── exercises.py
│   └── quiz.md
└── 05_integration_testing/
    ├── README.md
    ├── examples.py
    ├── exercises.py
    └── quiz.md

Ready to start? Begin with 01_why_testing!