There is one by Google : https://github.com/bslatkin/dpxdt. A friend of mine, Shashank Mehta, has been working on another similar tool called Bozo which tries to be a step ahead by providing cross-browser compatibility. The tool is not opensource yet but would be soon. He even proposed a talk around it in Jsfoo2015. https://jsfoo.talkfunnel.com/2015/45-automating-cross-browse...
Will update here with the link once the tool is open-sourced.