Book Image

Agile Technical Practices Distilled

By : Pedro M. Santos, Marco Consolaro, Alessandro Di Gioia
Book Image

Agile Technical Practices Distilled

By: Pedro M. Santos, Marco Consolaro, Alessandro Di Gioia

Overview of this book

The number of popular technical practices has grown exponentially in the last few years. Learning the common fundamental software development practices can help you become a better programmer. This book uses the term Agile as a wide umbrella and covers Agile principles and practices, as well as most methodologies associated with it. You’ll begin by discovering how driver-navigator, chess clock, and other techniques used in the pair programming approach introduce discipline while writing code. You’ll then learn to safely change the design of your code using refactoring. While learning these techniques, you’ll also explore various best practices to write efficient tests. The concluding chapters of the book delve deep into the SOLID principles - the five design principles that you can use to make your software more understandable, flexible and maintainable. By the end of the book, you will have discovered new ideas for improving your software design skills, the relationship within your team, and the way your business works.
Table of Contents (31 chapters)
Free Chapter
Section 1
Section 2
Section 3
Section 4
Chapter 21
License: CyberDojo

Test Doubles Guidelines

Only Use Test Doubles for Classes That You Own

Using Test Doubles is a technique for software design. That's why it is important to only mock/stub types that belong to the team's code base. The key concept here is that if the Test Doubles are coupled with an external interface, they cannot change the design to respond to requirements that arise from the process.

The same is valid for fixed types, such as those defined by the runtime or external libraries. So, how do we test the interaction with an external library? The trick here is to write a thin wrapper to implement the abstractions for the underlying infrastructure. Those wrappers are the components belonging to the team's code base that:

  • Are generated from a behavior-first position (public interface definition first)
  • Can be substituted with Test Doubles

We have found this to be great insight for understanding the technique. It restores the pre-eminence of design in...