What are the best JavaScript unit testing frameworks?

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score 22 · Answer 1

Mocha

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Top Pro

Supports different assertion libraries

Mocha runs independently from the assertion library, so you can choose which assertion format works best for you. Mocha most often is run in combination with assertion library Chai. See More

Top Con

No atomic tests

Tests cannot be ran in random order. See More

Top Pro

Write tests with Behavior Driven Development (BDD)

Allows developers to choose their development process. Not only TDD but also BDD. See More

Top Con

Can be intimidating for beginners

While some testing frameworks are complete out of the box, Mocha requires developers to select and set up assertion libraries and mocking utilities. For someone who is just starting to learn how to build tests this can be scary as they will also have to choose which libraries to use and learn them too. See More

Top Pro

Makes Asynchronous testing extremely easy

No need to write tricky statements for Async testing. Mocha gives you a done callback. Place this done parameter in your callback function, that'll let Mocha know that you've written an asynchronous function. See More

Top Pro

Integrates really well with NodeJS

The Mocha test framework itself runs on NodeJS, hence it makes everything related to it extremely simple. With Mocha's simple syntax and speed, testing your node.js app just got a whole lot easier. See More

Top Pro

Runs in Node.js and the browser

Mocha has a browser build as well as a node command line program so you can test in client and server side environments. See More

Top Pro

Custom full color test reporters

Mocha has multiple test reporters built in and you can create your own as well. The test reporters have full color and makes it easy to see if your tests fail or not. See More

Top Pro

Easy to add support for Generators

Aside from the numerous benefits with generators in your application, You can now also integrate generators into your test suite. By using mocha, all you have to do is enable support for generators. See More

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score 13 · Answer 2

Jest

Top Pro

Recommended for React testing

Jest is the recommended unit testing framework by Facebook. It's also the one used by Facebook developers when working with React projects. See More

Top Con

Not beginner-friendly

If you're new to unit testing and are trying to understand unit testing within the React ecosystem, specifically ReactNative, it is going to be a challenge. The Jest doc dives right into making tests without any primer on how to go from concept to implementation. See More

Top Pro

Well documented

Top Pro

Easy to use

One of Jest's philosophies is to provide an integrated “zero-configuration” experience. Eg: it provides assertion library by default. See More

Top Pro

Snapshot testing is convinient

It's great for testing UI. It is also convenient for asserting complex data objects, as it doesn't require developers to manually compose the expected value. See More

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score 12 · Answer 3

Jasmine

Top Pro

Behaviour Driven Development focused

If you prefer your test cases and application to be developed from the perspective of your stake holders, Jasmine is the framework for you. See More

Top Con

Not much room for flexibility

Jasmine comes with everything already baked in (including assertion libraries and mocking utilities). While this is great for beginners and people who don't want to spend much time looking into different libraries and tools it can be a turnoff for anyone who wants to use a different assertion and/or mocking library. See More

Top Pro

Has a very readable and user-friendly syntax

Code readability is an important factor, if the application development involves multiple teams; if the testing team is unable to read your test cases then they won't be able to test it. Jasmine resolves this issue by providing developers with an extremely simple and "human-friendly" syntax. See More

Top Pro

Includes assertions and mocking

Top Pro

Allows both DOM-less as well as Asynchronous testing

If you have some test cases that do not involve testing of DOM elements or events, those are exactly the ones where you want to use Jasmine. It'll provide smooth, simple and easy DOM-less testing of those test cases. See More

Top Pro

Supported by many CI servers (TeamCity, Codeship, etc.)

and some that don’t support natively have plugins (jenkins has a maven plugin) Descriptive syntax for BDD paradigm See More

Top Pro

Integrates very well with Ruby on Rails

The jasmine-rails gem allows you to run Jasmine specs in a browser (powered by Rails engine mounted into your application). See More

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score 7 · Answer 4

tape

Top Pro

Simple API

Very simple API that doesn't require globals, or monkey patching objects for assertions. See More

Top Con

No concurrency

Cannot run async test cases concurrently for faster test builds. See More

Top Pro

Built-in assert

This way you don't have to add more dependencies and external assertion libraries. See More

Top Pro

No global functions

Tape does not use global methods such as "it", "describe", since they are not considered best practice in JavaScript. See More

Top Pro

It follows the principles of TAP

TAP: Test Anything Protocol See More

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score 1 · Answer 5

QUnit

Top Con

Doesn't support source maps

QUnit has no support for sourcemaps. See More

Top Pro

Tests run in the order they're added to the suite

If you want your tests to run in the order you have provided (maybe if your tests are ordered in such a way that your current test relies on the previous one), you can do so by setting QUnit.config.reorder = false and the tests will run in the order that you have provided. See More

Top Con

Testing of Async operations can be a little tough at times

QUnit expects you to call start() before an async function and stop() once it has stopped. This can be problematic when you have no way of knowing when exactly your function will start or stop. See More

Top Pro

Works really well if performing DOM Testing

All frontend developers already know the ease that jQuery framework has brought to their lives, in handling DOM events and accessing elements. Since Qunit was built as a part of jquery (is even used by jQuery itself for unit testing) hence it makes testing of DOM elements a lot easier. See More

Top Pro

Extremely easy to start from scratch

All you have to do is to include the QUnit library either from the CDN or from the local server and then create your testcases.js file and run it. The outputs will be displayed in a nice format in the browser. See More

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score 2 · Answer 6

Ava

Top Pro

Atomic tests

You can run tests in random order. See More

Top Pro

No globals

Doesn't use globals. See More

Top Pro

Promise support

Top Pro

Isolated tests

Each test is run in it's own environment. See More

See All

What are the best JavaScript unit testing frameworks?

The Best 1 of 6 OptionsWhy?

Mocha

Supports different assertion libraries

No atomic tests

Write tests with Behavior Driven Development (BDD)

Can be intimidating for beginners

Makes Asynchronous testing extremely easy

Integrates really well with NodeJS

Runs in Node.js and the browser

Custom full color test reporters

Easy to add support for Generators

5 Other Options Considered

Jest

Recommended for React testing

Not beginner-friendly

Well documented

Easy to use

Snapshot testing is convinient

Jasmine

Behaviour Driven Development focused

Not much room for flexibility

Has a very readable and user-friendly syntax

Includes assertions and mocking

Allows both DOM-less as well as Asynchronous testing

Supported by many CI servers (TeamCity, Codeship, etc.)

Integrates very well with Ruby on Rails

tape

Simple API

No concurrency

Built-in assert

No global functions

It follows the principles of TAP

QUnit

Doesn't support source maps

Tests run in the order they're added to the suite

Testing of Async operations can be a little tough at times

Works really well if performing DOM Testing

Extremely easy to start from scratch

Ava

Atomic tests

No globals

Promise support

Isolated tests

Don't see your favorite option? Add it.

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