A question about git-rev-list

Hi,

if I do

git-rev-list --remove-empty HEAD --not some-commit -- filename | tail -1

do I have any guarantee that the commit id I get (if any) is a direct descendant of some-commit? I _think_ --remove-empty might be necessary for that option, but have no idea whether this hunch is correct. Do I need additional options like --topo-order, or is that unnecessary?

Thanks,