rspec/rspec-support — pull request #69 by phiggins (2014-05-25 23:14:05+00:00)
Title: Call #to_s on output to avoid leaking Differ's implementation details.

Prior to this, the output of `Differ.diff` was an EncodedString if the arguments were diffable. An EncodedString mostly acts like a String, but nothing outside of Differ needs to know it exists.