Selenium vs PHPUnit comparison of testing frameworks
What are the differences between Selenium and PHPUnit?

Selenium

https://pypi.org/project/selenium/

PHPUnit

https://phpunit.de/
Programming language

Python

PHP

Category

Web Automation

Unit Testing

General info

Selenium is an open source tool used to test web applications

Selenium is a powerful testing tool which can send standard Python commands to different browsers, despite variations in browser design. It also provides extensions to emulate user interaction with browsers, a distribution server for scaling browser allocation, and the infrastructure for implementations of the W3C WebDriver specification that lets you write interchangeable code for all major web browsers

PHPUnit is a unit testing framework for the PHP programming language

PHPUnit is a programmer-oriented testing framework and is an instance of the xUnit architecture for unit testing frameworks.
xUnit
Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.

No

Yes

It's an instance of the xUnit architecture for unit testing frameworks
Client-side
Allows testing code execution on the client, such as a web browser

Yes

It is primarily a browser automation tool which tests front-end components and functionality

Yes

It can perform Unit tests and can test various front-end components and behaviours
Server-side
Allows testing the bahovior of a server-side code

Yes

It can perform Unit tests and can test various components and behaviours in the backend using a BDD or TDD approach

Yes

By performing unit tests on singular 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

By writing your Selenium WebDriver tests in PyTest, this gives you access to Pytest's powerful fixture model

Yes

By use of a setup code. The setup code consists of two Important template functions, the 'setUp()' function (called to create the objects to be tested) and 'tearDown()' function (called to cleanup the objects which you tested)
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

One can group fixtures if accessing Pytest's fixture model

Yes

It does support 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

By using a library such as Faker or Fake-factory

N/A

Licence
Licence type governing the use and redistribution of the software

Apache License 2.0

Creative Commons Attribution 3.0 Unported 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

It includes support for mocking

Yes

One of its main features is that PHPUnit comes with out of the box support for Mock objects
Grouping
Allows organizing tests in groups

Yes

By using the TestNG feature with which we can create groups and maintain them easily

Yes

It allows grouping of tests and by using the @group annotation one can tag a test to belong to one or more groups
Other
Other useful information about the testing framework