Re: [PATCH v6 0/8] push: update remote tags only with force

On Thu, Jan 17, 2013 at 7:06 PM, Jeff King [off-list ref] wrote:

However, if instead of the rule being
"blobs on the remote side cannot be replaced", if it becomes "the old
value on the remote side must be referenced by what we replace it with",
that _is_ something we can calculate reliably on the sending side.

Interesting.  I would have thought knowing reachability implied having
the old object in the sending repository.

And
that is logically an extension of the fast-forward rule, which is why I
suggested placing it with ref_newer (but the latter should probably be
extended to not suggest merging if we _know_ it is a non-commit object).

Sounds great, especially if it is not dependent on the sender actually
having the old object.  Until this is implemented, though, I don't
understand what was wrong with doing the checks in the
is_forwardable() helper function (of course after fixing the
regression/bug.)

Chris