Book Image

Test-Driven Development with PHP 8

By : Rainier Sarabia
Book Image

Test-Driven Development with PHP 8

By: Rainier Sarabia

Overview of this book

PHP web developers end up building complex enterprise projects without prior experience in test-driven and behavior-driven development which results in software that’s complex and difficult to maintain. This step-by-step guide helps you manage the complexities of large-scale web applications. It takes you through the processes of working on a project, starting from understanding business requirements and translating them into actual maintainable software, to automated deployments. You’ll learn how to break down business requirements into workable and actionable lists using Jira. Using those organized lists of business requirements, you’ll understand how to implement behavior-driven development (BDD) and test-driven development (TDD) to start writing maintainable PHP code. You’ll explore how to use the automated tests to help you stop introducing regressions to an application each time you release code by using continuous integration. By the end of this book, you’ll have learned how to start a PHP project, break down the requirements, build test scenarios and automated tests, and write more testable and maintainable PHP code. By learning these processes, you’ll be able to develop more maintainable, and reliable enterprise PHP applications.
Table of Contents (17 chapters)
Part 1 – Technical Background and Setup
Part 2 – Implementing Test-Driven Development in a PHP Project
Part 3 – Deployment Automation and Monitoring

TDD with the Interface Segregation Principle

Interfaces are very helpful, but sometimes it can be very easy to pollute them with capabilities that are not really supposed to be a part of the interface. I used to encounter this violation a lot. I was asking myself how I kept on creating empty methods with to-do comments, only to find classes a few months or years later, still with those to-do comments and the methods still empty.

I used to touch my interfaces first and stuff them with all the methods I thought I needed. Then, when I finally wrote the concrete implementations, these concrete classes mostly had empty methods in them.

An interface should only have methods that are specific to that interface. If there’s a method in there that is not entirely related to that interface, you need to segregate it into a different interface.

Let’s see that in action. Again, let’s start with a – you guessed it right – test:

  1. Open the codebase...