title: Symfony2 getting config params in unit test
body: <p>I have a Symfony2 service that is constructed using a parameter from config.yml using dependency injection. I'm now trying to unit test it and find that the unit test does not have access to the container and therefore the service. So I should built one myself using mock data. It would make sense to me if I could now read the config parameter (going first to config_test.yml then config.yml etc etc) but it appears that isn't possible either. This appears to make unit testing a service cumbersome as I would need to code the initialisation parameters into the test instead of the config files.</p>
  
  <p>If there really is no way to construct a service with parameters from config.yml during a unit test, does anyone know the logic as to why it is a Bad Thing™?</p>