I inherited a php project of 3rd party code with a good deal of company-specific customization lumped on top of it. Now I've got to upgrade it and the person who owned the project is the one I've replaced and no one else knows what changes are 3rd party changes and what changes are company specific.
It's not too terrible a situation because he did check in the initial version of the application from a few updates back. But then he checked in 2 or 3 updates and about 10 or 15 patches.
So, say I've got a completely generic 3rd party version from the company we bought the code from. How do I go about merging the changes the last developer made into a fresh version. We're using git.