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

Cucumber

https://github.com/cucumber/cucumber-ruby

WebdriverIO

https://webdriver.io/
Programming language

Ruby

JavaScript

Category

Acceptance Testing

Browser Automation, Unit Testing, Functional Testing

General info

An automation tool for Behavior-Driven Development

The specifications are written in plain texts, which allows them to be easily understandable for all stakeholders. Cucumber Framework also supports languages beyond Ruby e.g. Java, JavaScript and Scala.

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.

No

Yes

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

Yes

You can test the front-end part like the GUI using cucumber and selenium, they integrate well to test your front-end.

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 back-end components such as APIs using rest & soap clients, and databases using whatever client libraries were provided by the libraries that existed in those stacks

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

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

Using the cucumber extension aruba you can create fixures in two steps: 1.Create a fixtures-directory; 2.Create fixture files in this directory

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

You can group your fixtures inside your fixtures directories

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

By using all of RSpec’s supported mocking frameworks (RSpec, Mocha, RR, Flexmock)

Yes

It contains a mocking service called 'wdio-wiremock-service'
Grouping
Allows organizing tests in groups

No

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