Mastering Jest: A Complete Guide to Testing

Gain insights into Jest, a versatile testing framework. Learn about fundamental and advanced testing techniques, from unit tests to CI/CD integration, for comprehensive JavaScript application testing.

Beginner

52 Lessons

12h

Certificate of Completion

AI-POWERED

Explanations

AI-POWERED

Explanations

This course includes

2 Projects

44 Playgrounds

8 Quizzes

This course includes

2 Projects

44 Playgrounds

8 Quizzes

Course Overview

Jest is a framework for testing applications developed in JavaScript. It has a well-documented and well-maintained range of tools to run tests in parallel. It is simple and works with projects using Babel, TypeScript, Node, React, Angular, Vue, etc. It works well for both client and server testing. This course covers Jest in-depth and is agnostic of any specific JavaScript framework. The course begins with the fundamentals of Jest testing, deconstructing the components of a test and covering how to compos...Show More

TAKEAWAY SKILLS

Unit Testing

Jest

Javascript

Javascript Testing

Frontend Testing

What You'll Learn

Hands-on experience with writing clean and meaningful tests for any JavaScript code

An understanding of the best practices for writing JavaScript tests

Working knowledge of implementing testing coverage requirements in an application

Familiarity with mocking the internal and external dependencies for testing

The use of integrated test suites with a CI/CD pipeline

Configuration of a testing environment for your needs

What You'll Learn

Hands-on experience with writing clean and meaningful tests for any JavaScript code

Course Content

Introduction

Get familiar with Jest, a JavaScript testing framework, and its three primary test types.

Test with Jest

Types of Tests in Jest

Setting Up Jest

Look at configuring Jest for TypeScript, structuring tests, and effective debugging techniques.

Jest and TypeScript

The Composition of a Test

Debugging the Tests

Quiz on Jest Fundamentals

Jest Matchers

Break apart common matchers, error handling, Jest Extended, and creating custom matchers in Jest.

Using Common Matchers

Testing Error Handling

The Jest Extended Library

Writing Custom Matchers

Quiz on Jest Matchers

Writing Unit Tests

Break down complex ideas for structuring, enhancing, and illustrating unit tests with Jest.

Introduction to Unit Test

Structuring Clean Tests

Additional Globals

Unit Test Examples

Quiz on Writing Unit Tests

Writing Snapshot Tests

Deepen your knowledge of snapshot testing in Jest to ensure UI consistency and accuracy.

Introduction to Snapshot Tests

Creating Snapshots

Maintaining Snapshots

Quiz on Writing Snapshot Tests

Asynchronous Code

5 Lessons

See how it works to test asynchronous code in Jest using callbacks, promises, and async/await.

Mocking

6 Lessons

Practice using mocking to simulate external dependencies for focused and isolated test environments.

Mocking External Libraries

8 Lessons

Break down the essential methods for mocking various external libraries with Jest.

Working with Jest Mocks

Project

Setup & Teardown

4 Lessons

Walk through test isolation, setup, and teardown in Jest for reliable test environments.

10.

Test Coverage & CI/CD Pipelines

4 Lessons

Work your way through test coverage essentials and CI/CD integration using GitHub Actions and CircleCI.

Test Coverage in Jest

Project

11.

Conclusion

1 Lesson

Enhance your skills in applying Jest to improve testing practices and developer productivity.

12.

Bonus: Best Practices

1 Lesson

Solve problems in Jest by focusing on isolation, mocking dependencies, and maintaining test coverage.

13.

Bonus: Resources for Continued Learning

1 Lesson

Investigate recommended resources like Jest documentation, blog articles, and integration guides.

14.

Appendix

2 Lessons

Master the steps to install, configure, and run Jest tests efficiently using various commands and options.

Course Author

Trusted by 1.4 million developers working at companies

Anthony Walker

@_webarchitect_

Evan Dunbar

ML Engineer

Carlos Matias La Borde

Software Developer

Souvik Kundu

Front-end Developer

Vinay Krishnaiah

Software Developer

Eric Downs

Musician/Entrepeneur

Kenan Eyvazov

DevOps Engineer

Souvik Kundu

Front-end Developer

Eric Downs

Musician/Entrepeneur

Anthony Walker

@_webarchitect_

Evan Dunbar

ML Engineer

Hands-on Learning Powered by AI

See how Educative uses AI to make your learning more immersive than ever before.

Instant Code Feedback

Evaluate and debug your code with the click of a button. Get real-time feedback on test cases, including time and space complexity of your solutions.

AI-Powered Mock Interviews

Put your skills to the test in a simulated interview setting. Receive personalized feedback based on your performance. Available in Premium & Premium Plus plans.

Adaptive Learning

At various checkpoints throughout Educative courses, you will be prompted to take a quick assessment. Receive a condensed curriculum tailored to your strengths and skill gaps.

Explain with AI

Select any text within any Educative course, and get an instant explanation — without ever leaving your browser.

AI Code Mentor

AI Code Mentor helps you quickly identify errors in your code, learn from your mistakes, and nudge you in the right direction — just like a 1:1 tutor!

FOR TEAMS

Interested in this course for your business or team?

Unlock this course (and 1,000+ more) for your entire org with DevPath