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

Jest

https://jestjs.io

RSpec

https://rspec.info
Programming language

JavaScript

Ruby

Category

Unit Testing

Unit Testing, Intergration Testing

General info

A Unit Testing framework focused on simplicity

This is a Unit test framwork especially designed for the React.JS, Babel, TypeScript, Node, React, Angular and Vue projects. It usually worked with Enzyme(Integration testing)

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.
xUnit
Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.

No

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

Yes

You can easily test methods, properties, UI element actions and other front-end functionalities

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.
Server-side
Allows testing the bahovior of a server-side code

Yes

Back-end server behaviour also can be tested with Jest much in the same way as the front-end tests.

Yes

You can test server-side behaviour with Rspec
Fixtures
Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test

Yes

Fixtures are supported, Jest has many helper functions such as: BeforeEach and afterEach If you have some work you need to do repeatedly for many tests, beforeAll and afterAll if you only need to do setup once, at the beginning of a file.

Yes

RSpec does contain fixture methods
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

Jest supports group fixtures

Yes

Group fixture methods are supported
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.

N/A

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

MIT 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)

Jest uses a custom resolver for imports in your tests making it simple to mock any object outside of your test’s scope. You can use mocked imports with the rich Mock Functions API to spy on function calls with readable test syntax.

Yes

Available through rspec-mocks gem.
Grouping
Allows organizing tests in groups

Yes

You can declare as many test suites as you want. Grouping of tests together is done using a describe block

Yes

Allows declaring example groups and contexts.
Other
Other useful information about the testing framework