
Beyond Compare
Beyond Compare allows you to compare files and folders. By using simple, powerful commands you can focus on the differences you're interested in and ignore those you're not.
This is actually Meld itself ported to Mac. Doesn't require X and keybinding changed to be adapt Mac shortcuts.
meld is a visual diff and merge tool targeted at developers. meld helps you compare files, directories, and version controlled projects. it provides two and threeway comparison of both files and directories, and has support for many popular version control systems.
on os x, meld is not yet officially supported. the best option are these prebuilt binaries. you can also get meld from macports, fink or brew; none of these methods are supported.
Productivity Developer Tools File Management
python diff merge-folders