HomeCoursesMastering Jest: A Complete Guide to Testing

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12h

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.

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Overview

Content

Reviews

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 compose basic unit tests and snapshot tests with Jest correctly. Next, it shows the testing of asynchronous code and the code that relies on external dependencies. Lastly, this course illustrates how Jest testing can effectively integrate into the real-world software development cycle through CI/CD pipeline. It gives you hands-on experience in setting up Jest, types of testing, testing coverage, mocking, and native tooling depth.

Jest is a framework for testing applications developed in JavaScript. It has a well-documented and well-maintained range of tool...Show More

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

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

TAKEAWAY SKILLS

Unit Testing

Jest

JavaScript

JavaScript Testing

Frontend Testing

Content

52 Lessons2 Projects8 Quizzes

Introduction

2 Lessons

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

4 Lessons

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

5 Lessons

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

5 Lessons

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

4 Lessons

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.

The Problem

Testing with Callbacks

Testing with Promises

Testing with Async/Await

Quiz on Testing Asynchronous Code

Mocking

6 Lessons

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

Introduction to Mocking

Mocking External Libraries

8 Lessons

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

Introduction to Mocking Packages

Axios

Dates

Google Analytics Data

Working with Jest Mocks

Project

Setup & Teardown

4 Lessons

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

Isolating Tests

Testing Setup

Testing Teardown

Quiz on Setup and Teardown

10.

Test Coverage & CI/CD Pipelines

4 Lessons

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

Setting Up Test Coverage

Integrating with GitHub Actions

Integrating with CircleCI

Quiz on Test Coverage and CI/CD Pipelines

Test Coverage in Jest

Project

11.

Conclusion

1 Lessons

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

Conclusion

12.

Bonus: Best Practices

1 Lessons

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

Best Practices for Testing with Jest

13.

Bonus: Resources for Continued Learning

1 Lessons

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

Recommended Resources

14.

Appendix

2 Lessons

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

Installing & Running Jest

The Jest Config File

Certificate of Completion

Showcase your accomplishment by sharing your certificate of completion.

Course Author:

Bryn Bennett

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Build prompt engineering skills. Practice implementing AI-informed solutions.

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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.

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