phpspec/phpspec — pull request #493 by docteurklein (2014-08-29 12:29:41+00:00)
Title: allow to initialize list of engines of Differ

example of usage:

https://github.com/docteurklein/event-store/blob/44a78e9c38ae3524e91dd5623fb743301a07bc03/src/TestWork/PhpSpecExtension/ExceptionStringer.php#L28