To follow along with the examples and exercises in this chapter, you will need to have a basic understanding of Angular and TypeScript, as well as a code editor, such as Visual Studio Code, installed on your computer

All the code files for this chapter can be found at https://github.com/PacktPublishing/Mastering-Angular-Test-Driven-Development/tree/main/Chapter%201.

In this section, we will explore the fundamentals of TDD and its role in Angular development. We’ll start by discussing the benefits of using TDD in general, such as improved code quality, faster development cycles, and reduced debugging time. Then, we’ll look at how TDD fits into the overall Angular development process and how it can be used to create scalable and maintainable applications.

What is Angular and TDD?

Angular is a popular open source JavaScript framework that’s used for building complex web applications. It was developed by Google and is widely used by developers around the world. Angular provides a set of tools and features that make it easy to build dynamic, responsive, and scalable web applications.

Angular is a component-based framework that allows developers to build reusable UI components. These components can be combined to create complex user interfaces, making it easy to maintain and extend...

With a theoretical understanding of TDD and its role in Angular application development, the next step is to configure our development environment so that we can apply TDD principles in Angular. To do this, we need to install the required tools to create an Angular project. By following the right steps, we can create a development environment that promotes effective and efficient development using TDD principles in Angular.

Setting up a development environment for Angular can be a bit more complex than setting up a general development environment. However, with the right guidance, it can be a straightforward process. Here, we will go over the steps you need to take to set up your Angular development environment. So, let’s get started.

Installing Node.js on Windows or macOS

Follow these steps to install Node.js on Windows or macOS:

1. Go to the official Node.js website (https://nodejs.org/en/) and click on the Download button...

With our development environment set up and ready, we can create our Angular project. This involves using the Angular CLI to generate the basic structure of our project, including files and folders. Once created, we can begin building our Angular application using the powerful tools and features provided by the framework.

After installing the Angular CLI, you can create a new Angular project by running the following command in your terminal:

$ ng new getting-started-angular-tdd --routing

This will create a new Angular project called getting-started-angular-tdd in the current directory.

After creating your Angular project, you can serve it by running the following command in your terminal:

$ cd getting-started-angular-tdd
$ ng serve --open

This will start a development server and open your application in your default browser. Here, you can make changes to your code and see the changes live in your browser.

Now, it’s time to explore...

Now that we’ve created the Angular project, we will explore the different files related to writing tests in Angular. I will provide insights into their role and best practices for working with them. Let’s get started.

*.spec.ts files

*.spec.ts files contain the actual test cases that will be run against your code. These files are the backbone of testing in Angular as they define the individual test cases that will ensure your code works as expected. The name of the file should match the name of the file being tested, and it should be located in the same directory as the file being tested. The tests in these files are organized into test suites, which are defined using the describe() function. Each test case is defined using the it() function. For example, if you were testing a component named MyComponent, you would create a file named my-component.spec.ts and define the test cases for that component within that...

This chapter covered the basics of TDD and its role in Angular. We explained the benefits of TDD and how it can help developers write high-quality code. Then, we discussed how to set up the development environment for Angular and created a new Angular project using the Angular programming interface. We also explored the various files related to writing tests in Angular, including *.spec.ts, karma.conf.js,tsconfig.spec.json, and src/test.ts. We provided detailed explanations of each file and their role in testing Angular applications. By understanding these files and their purpose, developers can write and run tests for their Angular applications more effectively and ensure that their code performs as expected.

In the next chapter, we’ll learn about the process of writing and executing unit tests using Jasmine while covering topics such as test suites, test specifications, and matchers.