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

RSpec

https://rspec.info

Minitest

https://github.com/seattlerb/minitest
Programming language

Ruby

Ruby

Category

Unit Testing, Intergration Testing

Unit 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.

Complete suite of testing facilities

Minitest is small, fast, and it aims to make tests clean and readable. It supports test-driven development (TDD), behavior-driven development (BDD), mocking, and benchmarking.
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.

Yes

MiniTest is an xUnit style framework in that is has assertion functions in the style of xUnit/TDD
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.

No

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

Yes

You can test server-side behaviour with Rspec

Yes

You can test various back-end components
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

Yes

Minitest supports test fixture functions
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

Yes

Minitest has group fixtures
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

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)

Yes

Available through rspec-mocks gem.

Yes

Mocking is available through the Minitest::Mock class which is a simple and clean mock object framework
Grouping
Allows organizing tests in groups

Yes

Allows declaring example groups and contexts.

Yes

Allows grouping by nested Ruby classes. RSpec-like "context" method is available for spec syntax through the minitest-spec-context extension gem
Other
Other useful information about the testing framework