pdfkit/pdfkit — pull request #270 by Igosuki (2014-12-02 13:59:58+00:00)
Title: feature(stylesheets): Handle StringIO as input for stylesheet)

This prevents having to write a file if it's already loaded in memory as a string (for instance, using Sprockets' Assets class).
It comes in handy for me since I'm reusing sass files and generating those files statically and not through middleware.