Mockery is a simple yet flexible PHP mock object framework
Highly opinionated mocking framework for PHP 5.3+
Virtual file system to mock the real file system in unit tests.
Mock Object library for PHPUnit
The Phake mock testing library
Behavior-Driven Development (BDD) library.
Experimental Mocking Framework powered by Aspects
The PHP Test Framework for Freedom, Truth and Justice.
PHPUnit: simple syntax to create mock-objects
Mock HTTP requests on the server side in your PHP unit tests
Provides base Symfony dependency injection container enabling service mocking.
FBMock is a PHP mocking framework designed to be simple and easy to use.
Guzzle Mock plugin
Mockista is library for mocking, which I've written, because I find mocking in PHPUnit awful.
Dependency injection for global functions.
Unit testing, mock objects and web testing framework for PHP built around test cases.
Behat extension for mocking services defined in the Symfony2 dependency injection container.
Ouzo PHP MVC framework
Helps you to build your mocks, stubs and test data in a nice oop way.
Shorthand for (PHPUnit) Mocking
Mock built-in PHP functions (e.g. time()) with PHPUnit. This package relies on PHP's namespace fallback policy. No further extension is needed.
Mocking utility for PHP functions and WordPress plugin API
Mock HTTP client
Mocks, stubs, and spies for PHP.
A library easing the combination of Phockito & PHP Unit