Test-first – Drive Clean Code with Automated Unit Tests

Master the Art of Test-driven Development (TDD) and learn how the Top 1% of Developers create software.

Created by: David Bieder
Software Engineer

What Will I Learn?

• Solve complex coding problems step-by-step with Test-first Programming (TDD)
• How to write tests before writing any production code with a simple 3-step technique
• How to get started with the first test in seconds – even if you haven't understood all details of the problem yet
• The secret to uncovering missing test cases so that you will always know what to do next
• Turn lousy tests into maintainable test cases that tell a story
• Sound like a test native by using Matchers in the most elegant way
• 3 things that will make you faster at writing Unit Tests
• 50 Refactoring Patterns you can use on a daily basis to keep your code clean
• A technique you can use to check if you've tested enough – or too little
• How to fix bugs with Test-first Programming and Test-driven Debugging
• 30 reasons why most developers hate writing tests – and how to avoid these common TDD anti-patterns
• Manage test data with the Bring Your Own principle
• Structure test code into The 4 Phases of a Test
• Eliminate code duplication with Test Lifecycle Hooks
• Get more out of your testing library with the Watch Mode
• (bonus) 9 Practice Challenges with solutions to help you reinforce and fine-tune your new skills
• (bonus) A Brief History of TDD
• (bonus) Why writing tests at the end sucks
• (bonus) The inconvenient truth about Code Coverage that nobody talks about
• (bonus) Use Test-first Programming to impress managers and your peers
• (bonus) How to approach Coding Challenges with confidence
• (bonus) Too DRY – When the Don't Repeat Yourself principle goes wrong
• (bonus) Why in computing Equal is not the Same

Requirements

• You WILL need basic programming skills. What you'll learn in this program is independent of any programming language. But you should be able to read simple code written in a C-family language. In this program, we will be using basic JavaScript. If you're familiar with C, C++, Java, Python, Swift, Objective-C, PHP, Ruby, or any similar language, you will be fine.
• You WON'T need previous testing experience. In fact, many developers with some testing experience will have to "unlearn" bad habits. So if you don't know anything about testing, you will have an advantage.
• You WILL need a macOS, Linux, or Windows computer to code along and for the exercises. We'll set up the development environment together at the beginning of the course.
• You WILL need a decent internet connection to watch the course videos and download the libraries and tools we will use in this course.

Target audience

• This course IS for SOFTWARE ENGINEERS of ALL LEVELS with AND without previous testing experience. The motivation for taking this course, however, will be different depending on your individual situation:
• This course IS for you if you're struggling with solving coding problems. Successful developers do not cook up working solutions in their brains. No, they solve problems systematically – one step after another. Test-first is a system that was invented for precisely that purpose. And everyone with some basic programming experience can learn it. Learn how to divide a problem into smaller chunks and solve these more digestible problems one at a time.
• This course IS for you if you already tried writing tests first and gave up. Most developers who gave up Test-first Programming never learned to do it properly. Usually, it is bad habits and anti-patterns that need to be blamed. Give Test-driven development another chance and learn how to do it right. Learn how to write testable code. Learn which tests are required and which aren't. Learn how to write good tests that make refactoring easier rather than harder. No more discussions about code coverage. No more: "I still need to add these missing tests."
• This course IS for you if you're uncertain if your code changes are any good or free of bugs. Are you 100% sure that your code works? Can it handle all the important edge cases? Is your code clean and maintainable? Are you confident that you didn't break anything? If your answer to any of these questions is not a clear YES!, you will benefit from learning Test-first Programming. You'll learn how to build a safety net that will give you confidence that things work as expected and protect you from breaking things. And you'll learn how to refactor your code into simple, self-explanatory solutions.
• This course IS for you if you're already struggling with writing tests. Do I need to test that? What should I test first? What should I test next? Is that a good test? Have I tested enough? Many developers hate writing tests. But writing tests can actually be fun – if you learn to do it right. Most of the problems developers have with writing tests originate from writing the tests after finishing the feature. Write tests first, and everyday obstacles around testing will simply disappear.
• This course IS for you if you plan to get into writing tests anyway. That's perfect. Test-first is actually the best way of learning how to write tests. You can start fresh, and you will not have to unlearn bad habits. You are like a raw diamond that waits to be cut and polished. Trying to test existing code that is not written with testability in mind is actually the worst-case scenario a developer can face. It's super hard. Learning to write tests by writing them first is much easier.
• This course IS for you if your job is no longer fun. Perhaps you have to work with a terrible codebase. Code files have hundreds of lines of code. Basic clean code principles are violated everywhere. You are afraid of breaking things by accident. Adding even simple features has become an energy-draining task. New bugs pop up all the time, and you are dreading the next release date already. Despite not accomplishing much, you feel stressed... If that sounds familiar, then Test-first Programming is for you. Creating a safety net of tests and refactoring the code is built right into the process, not an afterthought. The code will always be clean, and adding new features will be easy and fun again.
• This course is NOT for you if you're looking for an overnight solution. Test-first is a combination of techniques that require practice. You will not master Test-first Programming by just watching the videos. That's why I've added tons of practice challenges. I recommend you invest at least 2 hours per week (more if you can).
• This course is NOT for you if you're simply looking for a tutorial on how to use test framework X or Y. This program is not about a specific library or framework. Yes, you will learn how to use Jest and the many features that come with most test frameworks. But that's more like a side-effect of learning how to write tests first. Test-first Programming is a development approach that goes way beyond just writing tests. It's about writing clean, maintainable code that works. The incremental process involves continuous refactoring as well as deliberately applying software engineering principles.