Re: [PATCH 11/14] tree-diff: drop list-tail argument to diff_tree_paths()

Jeff King [off-list ref] writes:

The internals of the path diffing code, including ll_diff_tree_paths(),
all take an extra combine_diff_path parameter which they use as the tail
of a list of results, appending any new entries to it.

The public-facing diff_tree_paths() takes the same argument, but it just
makes the callers more awkward. They always start with a clean list, and
have to set up a fake head struct to pass in.

Let's keep the public API clean by always returning a new list. That
keeps the fake struct as an implementation detail of tree-diff.c.

Yes, this is much nicer.  I've always hated these code paths related
to "multitree" optimization, but these clean-ups make them more
palatable.

Thanks.