carlosmn/libgit2 — comment on commit 6f38bf6e78f21ace75998ea6ae5903ad541d86a6
File:  line 0
By peff:

How does recursion into sub-trees work? It looks like this just diffs a
single tree, and it is up to the callback to check each entry it gets
and say "Hey, this is a tree. I should probably see how the sub-entries
differ". And it's probably a good thing to be able to do a non-recursive
tree diff in some cases, because the caller might be doing something
tricky and want the efficiency.

But I expect most callers will want you to recurse, and give the full
pathname to their diff callback.