> - ; /* default mode; do nothing */
> + warning(_("--rebase-merges with an empty string "
> + "argument is deprecated and will stop "
> + "working in a future version of Git. Use "
> + "--rebase-merges=no-rebase-cousins "
> + "instead."));
Just a small nit on the warning message. It should describe to the user
what behavior is happening here and presumably the user wanted
`--rebase-merges` with no argument. For example, "Defaulting to
--rebase-merges instead."
