Book Image

Svelte with Test-Driven Development

By : Daniel Irvine
Book Image

Svelte with Test-Driven Development

By: Daniel Irvine

Overview of this book

Svelte is a popular front-end framework used for its focus on performance and user-friendliness, and test-driven development (TDD) is a powerful approach that helps in creating automated tests before writing code. By combining them, you can create efficient, maintainable code for modern applications. Svelte with Test-Driven Development will help you learn effective automated testing practices to build and maintain Svelte applications. In the first part of the book, you’ll find a guided walkthrough on building a SvelteKit application using the TDD workflow. You’ll uncover the main concepts for writing effective unit test cases and practical advice for developing solid, maintainable test suites that can speed up application development while remaining effective as the application evolves. In the next part of the book, you’ll focus on refactoring and advanced test techniques, such as using component mocks and writing BDD-style tests with the Cucumber.js framework. In the final part of the book, you’ll explore how to test complex application and framework features, including authentication, Svelte stores, and service workers. By the end of this book, you’ll be well-equipped to build test-driven Svelte applications by employing theoretical and practical knowledge.
Table of Contents (22 chapters)
1
Part 1: Learning the TDD Cycle
8
Part 2: Refactoring Tests and Application Code
16
Part 3: Testing SvelteKit Features

Saving Form Data

The preceding chapter introduced Playwright and SvelteKit routes. The data in our /birthdays route was hardcoded. In this chapter, we’ll force the real implementation of the load function by adding the ability to add new birthdays into the system.

Figure 4.1 shows the new form we’ll be building. It is attached to the bottom of the birthday list at the /birthdays route:

Figure 4.1 – The form for adding a new birthday

Figure 4.1 – The form for adding a new birthday

This chapter covers the following key topics:

  • Adding a Playwright test for data input
  • Test-driving a SvelteKit form
  • Test-driving a SvelteKit form action

By the end of the chapter, you’ll have a good understanding of how to test-drive SvelteKit forms.