Overview

Jest

Stacks10.0K

Followers4.1K

Votes175

Mocha

Stacks8.9K

Followers3.0K

Votes430

Jest vs Mocha: What are the differences?

Key Differences between Jest and Mocha

Jest and Mocha are both popular JavaScript testing frameworks often used in web development. While they share some similarities, there are several key differences between the two.

Testing Environment: Jest includes an out-of-the-box testing environment, making it easier to set up and use. On the other hand, Mocha requires additional setup and configuration to define and set up testing environments.
Assertion Library: Jest comes bundled with its own assertion library, whereas Mocha does not include one out of the box. However, Mocha supports a wide range of assertion libraries like Chai, Should.js, and Expect.js, giving developers more flexibility in choosing their preferred library.
Mocking and Spying: Jest offers built-in mocking and spying functionalities, making it easier to create and manage mocks and spies in tests. Mocha does not provide these features out of the box and requires additional libraries like Sinon.js to accomplish similar functionalities.
Performance: Jest is known for its fast and parallelized test execution, making it suitable for larger projects with extensive test suites. Mocha, on the other hand, may be slower in comparison, especially when dealing with large test suites or running tests in parallel.
Configuration: Jest comes with a pre-configured setup and requires minimal configuration, making it an ideal choice for projects with less complex testing needs. Mocha offers more flexibility but requires additional configuration to set up testing frameworks, assertion libraries, and other tools.
Reporting: Jest provides detailed and user-friendly test reports out of the box. It offers a comprehensive overview of test results, including test coverage. Mocha, on the other hand, does not provide built-in test reporting, requiring the use of additional libraries or plugins for generating test reports.

In summary, Jest is a powerful testing framework that offers an easy setup, includes its own assertion library, built-in mocking and spying functionalities, and provides detailed test reports. On the other hand, Mocha offers more flexibility in terms of testing environment, assertion library choice, and configuration options, making it suitable for projects with specific requirements.

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Advice on Jest, Mocha

Dane

Feb 7, 2020

Needs adviceon

Cypress

Jest

As we all know testing is an important part of any application. To assist with our testing we are going to use both Cypress and Jest. We feel these tools complement each other and will help us get good coverage of our code. We will use Cypress for our end to end testing as we've found it quite user friendly. Jest will be used for our unit tests because we've seen how many larger companies use it with great success.

835k views835k

Comments

Abigail

Dec 10, 2019

Decided

We use Mocha for our FDA verification testing. It's integrated into Meteor, our upstream web application framework. We like how battle tested it is, its' syntax, its' options of reporters, and countless other features. Most everybody can agree on mocha, and that gets us half-way through our FDA verification and validation (V&V) testing strategy.

231k views231k

Comments

Anonymous

Feb 6, 2020

Needs advice

Postman will be used to do integration testing with the backend API we create. It offers a clean interface to create many requests, and you can even organize these requests into collections. It helps to test the backend API first to make sure it's working before using it in the front-end. Jest can also be used for testing and is already embedded into React. Not only does it offer unit testing support in javascript, it can also do snapshot testing for the front-end to make sure components are rendering correctly. Enzyme is complementary to Jest and offers more functions such as shallow rendering. UnitTest will be used for Python testing as it is simple, has a lot of functionality and already built in with python. Sentry will be used for keeping track of errors as it is also easily integratable with Heroku because they offer it as an add-on. LogDNA will be used for tracking logs which are not errors and is also a Heroku add-on. Its good to have a separate service to record logs, monitor, track and even fix errors in real-time so our application can run more smoothly.

290k views290k

Comments

Detailed Comparison

Jest	Mocha
Jest provides you with multiple layers on top of Jasmine.	Mocha is a feature-rich JavaScript test framework running on node.js and the browser, making asynchronous testing simple and fun. Mocha tests run serially, allowing for flexible and accurate reporting, while mapping uncaught exceptions to the correct test cases.
Familiar Approach: Built on top of the Jasmine test framework, using familiar expect(value).toBe(other) assertions;Mock by Default: Automatically mocks CommonJS modules returned by require(), making most existing code testable;Short Feedback Loop: DOM APIs are mocked and tests run in parallel via a small node.js command line utility	browser support;simple async support, including promises;test coverage reporting;string diff support;javascript API for running tests;proper exit status for CI support etc;auto-detects and disables coloring for non-ttys;maps uncaught exceptions to the correct test case;async test timeout support;test-specific timeouts;growl notification support;reports test durations;highlights slow tests;file watcher support;global variable leak detection
Statistics
Stacks 10.0K	Stacks 8.9K
Followers 4.1K	Followers 3.0K
Votes 175	Votes 430
Pros & Cons
Pros 36 Open source 32 Mock by default makes testing much simpler 23 Testing React Native Apps 20 Parallel test running 16 Fast Cons 4 Documentation 4 Ambiguous configuration 3 Difficult 2 Ambiguous 2 Difficult to run single test/describe/file	Pros 137 Open source 102 Simple 81 Promise support 48 Flexible 29 Easy to add support for Generators Cons 3 Cannot test a promisified functions without assertion 2 No assertion count in results 1 Not as many reporter options as Jest

What are some alternatives to Jest, Mocha?

Jasmine

Jasmine is a Behavior Driven Development testing framework for JavaScript. It does not rely on browsers, DOM, or any JavaScript framework. Thus it's suited for websites, Node.js projects, or anywhere that JavaScript can run.

Cypress

Cypress is a front end automated testing application created for the modern web. Cypress is built on a new architecture and runs in the same run-loop as the application being tested. As a result Cypress provides better, faster, and more reliable testing for anything that runs in a browser. Cypress works on any front-end framework or website.

CodeceptJS

It is a modern end to end testing framework with a special BDD-style syntax. The test is written as a linear scenario of user's action on a site. Each test is described inside a Scenario function with I object passed into it.

Protractor

Protractor is an end-to-end test framework for Angular and AngularJS applications. Protractor runs tests against your application running in a real browser, interacting with it as a user would.

AVA

Even though JavaScript is single-threaded, IO in Node.js can happen in parallel due to its async nature. AVA takes advantage of this and runs your tests concurrently, which is especially beneficial for IO heavy tests. In addition, test files are run in parallel as separate processes, giving you even better performance and an isolated environment for each test file.

Ghost Inspector

It lets you create and manage UI tests that check specific functionality in your website or application. We execute these automated browser tests continuously from the cloud and alert you if anything breaks.

QUnit

QUnit is a powerful, easy-to-use JavaScript unit testing framework. It's used by the jQuery, jQuery UI and jQuery Mobile projects and is capable of testing any generic JavaScript code, including itself!

Sorry-cypress

Open-source, self-hosted alternative Cypress Dashboard.

Baretest

It is a fast and simple JavaScript test runner. It offers near-instant performance and a brainless API. It makes testing tolerable.

SinonJS

It is a really helpful library when you want to unit test your code. It supports spies, stubs, and mocks. The library has cross browser support and also can run on the server using Node.js.