Book Image

React Design Patterns and Best Practices

By : Michele Bertoli
Book Image

React Design Patterns and Best Practices

By: Michele Bertoli

Overview of this book

Taking a complete journey through the most valuable design patterns in React, this book demonstrates how to apply design patterns and best practices in real-life situations, whether that’s for new or already existing projects. It will help you to make your applications more flexible, perform better, and easier to maintain – giving your workflow a huge boost when it comes to speed without reducing quality. We’ll begin by understanding the internals of React before gradually moving on to writing clean and maintainable code. We’ll build components that are reusable across the application, structure applications, and create forms that actually work. Then we’ll style React components and optimize them to make applications faster and more responsive. Finally, we’ll write tests effectively and you’ll learn how to contribute to React and its ecosystem. By the end of the book, you’ll be saved from a lot of trial and error and developmental headaches, and you will be on the road to becoming a React expert.
Table of Contents (19 chapters)
React Design Patterns and Best Practices
About the Author
About the Reviewer
Customer Feedback

Code coverage tools

There are many reasons to write tests and we went through some of them in the previous section. The main one is always to provide value to our codebase and make it more robust.

Because of that, I am always skeptical when it comes to counting the number of tests, the lines of code, and the test coverage. I suggest people don't focus on numbers but on the value that the tests can provide.

However, in some scenarios it is useful to get some measurement of the coverage and keep track of the numbers. In big projects with many different modules, doing so makes it easy to spot files that have not been adequately tested or that have not been tested at all.

Once again, Jest provides all the equipment you need to run your tests and of course it provides the functionalities to measure and store the code coverage information.

It uses Istanbul, one of the most popular code coverage libraries, which you will have to install manually if you are using Mocha.

Running the coverage with Jest...