Matthew DeVore [off-list ref] writes:
quoted
It is more like "this is a set operation across commits. We also
show objects that are reachable from the commits in the resulting
set and are not reachable from the commits in the set that were
excluded when --objects option is given".
That would be correct though it wouldn't tell that you can use
"--objects ^foo-tree bar-tree."
Yeah, but quite honestly, I consider that it is working by accident,
not by design, in the current code (iow, you are looking at a
behaviour of whatever the code happens to do). "rev-list" is pretty
much set operation across commits, and anything that deals with a
non commit-ish given from the command line is an afterthought at
best, and happenstance in reality.
I do not mean to say that the code must stay that way, though.