Test-Driven Development

Test-Driven Development (TDD) is a proven method for developing software quickly and efficiently. It involves first writing a failing test and then creating only as much productive code as is necessary to pass that test. When used correctly, this results in very lean program code that is 100% tested.

In the modern development process, humans write the tests while AI agents generate the production code. This keeps control over requirements and quality in human hands, while AI takes care of implementation. The tests serve as specifications and guarantee that the generated code actually exhibits the desired behaviour. This approach ensures higher code quality and reduces errors, as the tests systematically define expectations and the AI only delivers code that meets these expectations.

In this training, you will learn about test-driven programming and experience first-hand how it works and what you need to bear in mind in ensemble programming. You will also see how AI agents can help with this.

This training uses the collaborative software development method Ensemble Programming, in which a team works on a task simultaneously.

In ensemble programming, everyone uses a shared setup with a screen and keyboard, with roles changing regularly. Typical roles include the "driver", who executes the steps decided by the team, the "navigator", who sets the plan, and the "facilitator", who monitors team dynamics.

The goal is to create high-quality code by sharing perspectives and expertise.

• What are the benefits of writing tests first?
• Chicago or London: inside-out or outside-in?
• Take the first steps with a guiding test
• How much testing is needed for the next step?
• When and how should I refactor?

This training is for developers who program professionally in PHP and have always been unhappy about not writing enough tests. The training is not necessarily about propagating TDD as the one true way of developing software, but rather about recognising the advantages of this approach and being able to switch between methodologies as required.

Prerequisites are practical experience with PHPUnit and knowledge of object-oriented programming in PHP. The necessary basics are taught in Test Automation with PHPUnit.

• Improve the code quality and design of your software
• Avoid writing unnecessary code
• Ensure sure that code is covered by tests