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

RSpec

https://rspec.info

Intern

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

Ruby

JavaScript

Category

Unit Testing, Intergration Testing

Unit Testing, Functional Testing

General info

Domain Specific Language (DSL) testing solution for Ruby code

It focuses on empowering Test Driven Development (TDD). RSpec contains multiple smaller libraries, which may be independently used with other testing frameworks.

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

Yes, but it differs from more traiditional xUnit solutions. Its tests are written in a "Tests as Specification" manner. This means that the terminology used in RSpec is adjusted to a language more fitting for specification.

No

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

Yes

RSpec is used to primarily test the behaviour of applications or individual components so it can test front-end behaviour as well - you can use capybara gem with RSpec for that.

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

You can test server-side behaviour with Rspec

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

RSpec does contain fixture methods

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 fixture methods are supported

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

RSpec contains generators for example intergration_'test_name' which will save a spec inside the spec/requests folder

Licence
Licence type governing the use and redistribution of the software

MIT License

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

Available through rspec-mocks gem.

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

Allows declaring example groups and contexts.

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