Re: [Bug] In `git-rev-list(1)`, using the `--objects` flag doesn't work well with the `--not` flag, as non-commit objects are not excluded

>
> On Tue, Aug 15, 2023 at 12:31:37PM -0700, Junio C Hamano wrote:
> > Karthik Nayak <karthik.188@gmail.com> writes:
> >
> > > If you notice here, the objects
> > > `8baef1b4abc478178b004d62031cf7fe6db6f903`,
> > > `086885f71429e3599c8c903b0e9ed491f6522879` and
> > > `7a67abed5f99fdd3ee203dd137b9818d88b1bafd` are included in the output,
> > > these objects are reachable from
> > > `91fa9611a355db77a07f963c746d57f75af380da` and shouldn't have been
> > > included since we used the `--not` flag.
> >
> > For performance reasons, we cannot afford to enumerate all objects
> > that are reachable from --not objects and exclude them from the
> > output.  So it is a balancing act to decide where to draw the line.
>
> As a hack, you can exploit the existing bitmap traversal routine to
> build up an exact mapping of what is and isn't on either side of your
> reachability query.
>
> IOW, if you run:
>
>     git repack -ad --write-bitmap-index
>
> and then repeat the rev-list query with `--use-bitmap-index`, you should
> get exact results.
>
> Note that this will only work if pack.useBitmapBoundaryTraversal is set
> to false, since the boundary-based traversal that is behind that
> configuration option is susceptible to the same one-sided error.
>
> Thanks,
> Taylor