evanw/node-source-map-support — pull request #26 by ashaffer (2013-12-11 20:32:15+00:00)
Title: should not return a url when we have a dataUrl

If you return a dataUrl in the url field, the mapSourcePosition function will try to treat it as an actual url. In PhantomJS, this causes the path.dirname() function to basically fall into a blackhole trying to process a path regex on such a large string.