Adding fetch.type git as a variant?

[David Bruce]

Hi,

All of the SCM fetch types are discouraged in the manual for
"non-reproducible builds", which is fair enough.  But as the
maintainer of both the Portfile and the upstream project, it seems it
would be highly useful to have an automated way to see if the latest
git source breaks the macports build.  Is it possible/advisable to do
this as a variant, as there doesn't seem to be any option to tell port
to use a different fetch type, e.g. something like:

variant git_dev_only description {use latest git source} {
     fetch.type          git
     git.url                git://git.debian.org/git/tux4kids/t4k_common.git
     use_autoreconf  yes
}

plus whatever else is needed to get it to work.

Thanks for any advice,

David Bruce