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

	RSpec https://rspec.info	WebdriverIO https://webdriver.io/
Programming language	Ruby	JavaScript
Category	Unit Testing, Intergration Testing	Browser Automation, 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.	WebdriverIO is the next-gen WebDriver test framework for Node.js made upon Selenium WebdriverIO is written in JavaScript and uses Selenium under the hood. It also comes with its own inbuilt test runner and supports other testing frameworks like Jasmine, Cucumber, and Mocha
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
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 WebdriverIO allows the use of advanced CSS selectors and makes it easy to find elements for front-end testing
Server-side Allows testing the bahovior of a server-side code	Yes You can test server-side behaviour with Rspec	Yes It can be used to test server side behaviour and functionality
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 WebdriverIO supports the creation of fixtures
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 WebdriverIO supports the creation of 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	N/A
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 It contains a mocking service called 'wdio-wiremock-service'
Grouping Allows organizing tests in groups	Yes Allows declaring example groups and contexts.	Yes WebdriverIO allows one to build test suites, you can run these test in parallel and organize them by adjusting the 'maxInstances' property in your config file
Other Other useful information about the testing framework