Imagine an XML file (with no Text nodes) where every node has a unique id.
Imagine a user modifies a copy of this file. Modifications include adding some new nodes (deep in the hierarchy), modifying properties on a couple other nodes, and deleting some other nodes.
Imagine that the original XML file changes. I want to re-apply the work that user did, using the modified tree. I want to get a set of commands from a diff between the user's work and the original, and then apply those commands to the changed original.
This is more than a 3-way text merge primarily because nodes can be re-ordered or moved to a new point in the hierarchy, but the presence of the unique identifier on each node makes it possible to absolutely know that this is not a new node.
Anyone know of any projects that do this sort of thing? Algorithms? White papers? Web pages?