String diff = "";
if (!fromNode.getRevisionId().equals(toNode.getRevisionId())) {
// diff of node at given path
DiffBuilder diffBuilder = new DiffBuilder(MongoUtil.wrap(fromNode),
MongoUtil.wrap(toNode), path, 0, new SimpleMongoNodeStore(), path);
diff = diffBuilder.build();
}
// find out what changed below path
List<MongoCommit> commits = getCommits(fromCommit, toCommit);
Set<String> affectedPaths = new HashSet<String>();