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

	PHPUnit https://phpunit.de/	Spek https://www.spekframework.org/
Programming language	PHP	Kotlin
Category	Unit Testing	Acceptance Testing, Unit Testing
General info	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.	Spek is a specification framework for Kotlin Spek is a Kotlin-based Specification Testing framework for the JVM. It works as a JUnit 5 Test Engine meaning that we can easily plug it into any project that already uses JUnit 5 to run alongside any other tests that we might have.
xUnit Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.	Yes It's an instance of the xUnit architecture for unit testing frameworks	No
Client-side Allows testing code execution on the client, such as a web browser	Yes It can perform Unit tests and can test various front-end components and behaviours	Yes Yes you can test front-end behaviour by writing specifications to test front-end functionality. Developers can also write unit tests for individual front-end components.
Server-side Allows testing the bahovior of a server-side code	Yes By performing unit tests on singular back-end components	Yes You can test back-end behaviour and componets by writing specifications to test back-end functionality and unit tests for individual 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 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)	Yes Fixtures are available in spek through functions suchas beforeEachTest() and afterEachTest()
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 It does support group fixtures	Yes spek has group fixtures available through the beforeGroup() and afterGroup() functions
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.	N/A	N/A
Licence Licence type governing the use and redistribution of the software	Creative Commons Attribution 3.0 Unported License	Modified BSD 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 One of its main features is that PHPUnit comes with out of the box support for Mock objects	Yes You can use the third party library mockito-kotlin
Grouping Allows organizing tests in groups	Yes It allows grouping of tests and by using the @group annotation one can tag a test to belong to one or more groups	Yes Tests are written using nested lambdas, each scope (level) can either be a group or a test
Other Other useful information about the testing framework