MultiDiff is a tool I hacked together in a frenzy, 24-hour coding session. It is neither complete nor totally tested, but seems to do what I want. I started with the source for xdiff by Tim Krauskopf at NCSA, written 1988. Unfortunately that source contained several subtle bugs, as well as didn't do a complete compare of lines (just a hash) so what is in here now is heavily modified and expanded upon.
MultiDiff is a tool for comparing source code hiearchies, and outputting edit instructions (patch files) to change one hiearchy into another. It works on the basic assumption that folders do not move or change name, and files do not change name. It, however, handles the case of deleted or added files by outputting the text of the new files, or commands to delete the old file. Those delete commands are presently ignored when playing back the patch file.
MultiDiff ONLY works on TEXT files, it ignores other files. It will NOT generate instructions to create a whole new folder of files, unless the same folder (but empty) is in the original source tree.
Choose "Make Diff" to compare two folders and their subfolders and record changes in a patch file. Choose "Apply Diff" to apply a patch file to a folder. If you double-click a patch file, make sure it's IN THE TOP-MOST FOLDER YOU WANT THE PATCH TO APPLY ON or it won't find the files to work with. When you open a patch file from within the program, you may choose any folder to work on, and the patch file may be anywhere.
I can make no guarantee that this application won't chew up your hard disk or blow your Mac away. After all, it's designed to go crunching around file trees, and if a bug slipped past my slipshod testing, well, you worry about that since I won't let you use MultiDiff unless you take full responsibility for what you do with it.
There are some things missing, like the ability to set TEXT file creator (currently hard-coded to Metrowerks CodeWarrior) or choose to have "delete" instructions take effect (they're currently generated but ignored) It's also rather slow, because I tried to make it multitasking-friendly.
