Introducting gem2deb

[Lucas Nussbaum <lucas@lucas-nussbaum.net>]

Hi,

So, apparently I needed the feeling that I didn't have to worry anymore with
Ruby to get motivated again. I've spent some time today working on a
replacement for our packaging scripts, using dh7, and I made good progress.

It's called gem2deb. It's built as a set of small scripts, but combining them
later in a single "get me this gem and build me a .deb" tool will be easy, as
all the logic is in libraries.

I have reused the gem2tgz script from Antonio Terceiro (thanks!).

The targetted workflow looks like ([*] = almost fully implemented):
    Download gem:
    gem fetch foo [*]
        |
        v
    Create a tarball. It contains the gem spec as metadata.yml
    gem2tgz foo-1.2.gem [*]
        |
        v
    Convert to a Debian source package with sane defaults:
    dh-make-ruby foo-1.2.tar.gz [*]
        |
        v
    Modify, if needed
        |
        v
    Build the package:
    dpkg-buildpackage -us -uc

Current status:
gem2tgz and dh-make-ruby work. dh-make-ruby generates a Debian source package
that uses Debhelper 7 with a custom build system (ruby.pm) that calls a
"dh_ruby" script.
dh_ruby is not yet feature-comparable with setup.rb, and needs some work.

Contributions are very much welcomed. The tool is hosted on github:
https://github.com/ln/gem2deb
There's a number of FIXMEs in lib/gem2deb/dh_ruby.rb, if you are looking for
something to do. Also, I would appreciate a review of my code.

Let's just implement something that works, and then we can discuss boring stuff
such as policy and migration plan. That's for squeeze+1 anyway, of course.

Thanks,

- Lucas