diffed

https://github.com/Jun-Dai/diffed

This is a library for creating HTML from a unified diff string, built specifically for the diff section output by "perforce describe -du" or "git show [commit SHA]", but with an eye towards solving a more general problem. It supports two modes: with inline styles or with CSS classes(which you can style yourself). Either mode outputs an HTML table that you may want to include in a Web page or an HTML e-mail.