Mockery : Mockery is a simple yet flexible PHP mock object framework for use in unit testing with PHPUnit, PHPSpec or any other testing framework. Its core goal...
vfsStream : vfsStream is a stream wrapper for a virtual file system that may be helpful in unit tests to mock the real file system. It can be used with any unit t...
testify : Go code (golang) set of packages that provide many tools for testifying that your code will behave as you intend.
Humbug : Humbug is a Mutation Testing framework for PHP to measure the real effectiveness of your test suites and assist in their improvement. It eats Code Cov...
Pimple : Pimple is a small Dependency Injection Container for PHP 5.3 that consists of just one file and one class (about 50 lines of code).
PHPUnit is the de-facto standard for unit testing in PHP projects. It provides both a framework that makes the writing of tests easy as well as the functionality to easily run the tests and analyse their results.