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

pytest

https://docs.pytest.org/en/latest/

WebdriverIO

https://webdriver.io/
Programming language

Python

JavaScript

Category

Unit Testing

Browser Automation, Unit Testing, Functional Testing

General info

Pytest is the TDD 'all in one' testing framework for Python

Pytest is a powerful Python testing framework that can test all and levels of software. It is considered by many to be the best testing framework in Python with many projects on the internet having switched to it from other frameworks, including Mozilla and Dropbox. This is due to its many powerful features such as ‘assert‘ rewriting, a third-party plugin model and a powerful yet simple fixture model.

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

pytest can test any part of the stack including front-end components

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

pytest is powerful enough to test database and server components and functionality

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

Pytest has a powerful yet simple fixture model that is unmatched in any other testing framework.

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

Pytest's powerful fixture model allows grouping of fixtures

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

pytest has a hook function called pytest_generate_tests hook which is called when collecting a test function and one can use it to generate data

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 either using unittest.mock or using pytest-mock a thin wrapper that provides mock functionality for pytest

Yes

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

Yes

Tests can be grouped with pytest by use of markers which are applied to various tests and one can run tests with the marker applied

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