Symfony2 Mocker Extension
Behat extension for mocking services defined in the Symfony2 dependency injection container.
This extension was always a hack. For a better approach try https://github.com/docteurklein/TestDoubleBundle.
Use it sparingly. Mocking a service container is not a good practice. Most of the time if there's a need for this, the problem can be better solved by improving the design instead.