Test-Driven Development with Python, 3rd Edition

Preface

This book has been my attempt to share with the world the journey I took from “hacking” to “software engineering”. It’s mainly about testing, but there’s a lot more to it, as you’ll soon see.

I want to thank you for reading it.

If you bought a copy, then I’m very grateful. If you’re reading the free online version, then I’m still grateful that you’ve decided it’s worth spending your time on. Who knows; perhaps once you get to the end, you’ll decide it’s good enough to buy a physical copy for yourself or a friend.

If you have any comments, questions, or suggestions, I’d love to hear from you. You can reach me directly via [e-mail], or on Mastodon @hjwp. You can also check out the website and my blog.

I hope you’ll enjoy reading this book as much as I enjoyed writing it.

Why I Wrote a Book About Test-Driven Development

“Who are you, why have you written this book, and why should I read it?” I hear you ask.

I was lucky enough early on in my career to fall in with a bunch of test-driven development (TDD) fanatics, and it made such a big impact on my programming that I was burning to share it with everyone. You might say I had the enthusiasm of a recent convert, and the learning experience was still a recent memory for me, so that’s what led to the first edition, back in 2014.

When I first learned Python (from Mark Pilgrim’s excellent Dive Into Python), I came across the concept of TDD, and thought, “Yes. I can definitely see the sense in that”. Perhaps ...