Best way to get submodules into extracted source?

[Joshua Root]

On 2020-5-23 05:16 , Zhenfu Shi via macports-dev wrote:
> Hey guys,
> I’m trying updating transmission(-x11) to just-released version 3.0, but it uses a lot of 3rd party submodules. I found the macports guide reads "the best distfile candidate (if available) is a distfile from GitHub releases”, so I’d like to know what’s the best way to put submodules into the extracted tarball, without using `fetch.type git` and `git submodule update —init`. Would be great if there’s a port already doing this so I could learn from it.

GitHub's auto-generated tarballs do not contain submodules, which is
just one of the many reasons why projects should upload proper release
tarballs. Fortunately, transmission does this, so it's just a matter of
setting `github.tarball_from releases` and `use_xz yes`.

- Josh