Behat/Behat — pull request #664 by sstutz (2014-12-16 10:48:55+00:00)
Title: Passing file contents rather than filename

The ability to pass file names was deprecated in symfonys YAML component v2.2 and will be removed in 3.0.
since Behat uses "symfony/yaml": "~2.1" it'll fetch 2.2 as well and throws a PHP Deprecated Warning.