ExUnit vs Intern comparison of testing frameworks
What are the differences between ExUnit and Intern?

ExUnit

https://hexdocs.pm/ex_unit/ExUnit.html

Intern

https://github.com/theintern/intern
Programming language

Elixir

JavaScript

Category

Unit Testing

Unit Testing, Functional Testing

General info

Unit testing framework for Elixir.

Elixir comes bundled with ExUnit allowing developers to use all elixir features without compromising unit tests. It uses a TDD workflow, and shows one message per test

Intern is minimal test system for JavaScript designed to write and run consistent.

Intern is a complete test system for JavaScript designed to help you write and run consistent, high-quality test cases for your JavaScript libraries and applications. Using Intern we can write tests in JavaScript and TypeScript using any style like TDD, and BDD. Intern can run unit tests in most browsers that support ECMAScript
xUnit
Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.

Yes

xUnit has the ExUnit framework as an instance

No

Client-side
Allows testing code execution on the client, such as a web browser

Yes

Front-end code can be tested using ExUnit, Phoenix front-end framework for Elixir uses ExUnit as the default testing framework

Yes

Intern is a complete test system for JavaScript It Runs in the browser and can test any front-end component and functionality
Server-side
Allows testing the bahovior of a server-side code

Yes

ExUnit tests backend code. Typically Unit tests will be written not to interact with the browser, but with ExUnit you can test whichever part of your application

Yes

Since it is a complete testing system that can test any type of JavaScript code, it can test server-side behaviour and components as well
Fixtures
Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test

Yes

ExUnit has a library called ExUnitFixtures fixtures are functions that are run before a test is run to setup the test environment or provide the test with data

N/A

Group fixtures
Allows defining a fixed, specific states of data for a group of tests (group-fixtures). This ensures specific environment for a given group of tests.

Yes

Group fixures are possible with this library

N/A

Generators
Supports data generators for tests. Data generators generate input data for test. The test is then run for each input data produced in this way.

Yes

Generators are found in the StreamData module

Licence
Licence type governing the use and redistribution of the software

Apache License 2.0

FreeBSD License

Mocks
Mocks are objects that simulate the behavior of real objects. Using mocks allows testing some part of the code in isolation (with other parts mocked when needed)

Yes

Mocks are available for use with ExUnit through the Mock module. Also available through the use of third party libraries like mecktest

Intern uses the Dojo Toolkit’s AMD loader. To mock, you should be able to just use the standard AMD 'map' feature, else you can use third party libraries like sinon.js
Grouping
Allows organizing tests in groups

Yes

Using the 'describe' function which goups tests together. Every describe block recieves a name which is used as a prefix for upcoming tests

Yes

You can group tests into Suites which may be specified as file paths or using glob expressions, there is typically one top-level suite per module.
Other
Other useful information about the testing framework