[ruby-core:36440] Changes for Ruby in Debian (and Ubuntu)

Hi,

Since the beginning of 2011, the Debian Ruby team has been working on
several big changes. Those changes all are available in Debian unstable,
some of them are also available in Debian testing, and they should all
be available in the next Debian and Ubuntu releases.

I think that it addresses most of the reasonable concerns about Ruby in
Debian.

Using alternatives to switch between Ruby implementations
=========================================================
The alternatives system is now used to manage the "ruby" symlink and the
other related symlinks, making it easy to switch between Ruby
implementations (only Ruby 1.8 and 1.9.X at the moment). The default
choice for Ruby is still 1.8, but this change will make it easy for us
to make a switch to 1.9.X by default (likely by the release of Debian
wheezy).

Installing gems executables to /usr/local/bin
=============================================
Rubygems (both as a standalone package, and as shipped with Ruby 1.9.X)
now install executables to /usr/local/bin.

Enabling gem update --system
============================
gem update --system has been re-enabled. Since upgrading rubygems to a
version that may not have been properly tested with the rest of the
Debian system may cause issues in the user's system, there's a big
warning about that. The user can confirm and upgrade rubygems anyway by
defining an environment variable.

New gem2deb packaging helper
============================
There's a new packaging helper, named gem2deb, that makes it very easy
to generate Debian source packages from Rubygems. We are in the process
of migrating all ruby libraries packaged in Debian to that new helper.
It will take some time, though (help is welcomed).
transition status: http://pkg-ruby-extras.alioth.debian.org/wheezy/

One big benefit of the switch to gem2deb for the Ruby community is that,
in the process, we are enabling test suites at build time for each
package and each Ruby implementation. This should make it easy to detect
regressions in new interpreter versions.

Ruby 1.9.3
==========
We will switch to Ruby 1.9.3 ASAP (probably when it is branched off
trunk, with a package first in Debian experimental). Since the Ruby
compatibility version issue is likely to stay around, we will
re-evaluate how we are dealing with it (to avoid the ruby1.9.1 package
<=> ruby -v = 1.9.2 problem that confuses many users). This is likely by
switching the package name to ruby1.9.3 (keep a ruby1.9.1 package for
compatibility). The package containing the shared library will stay
libruby1.9.1.

Links
=====
team website: http://wiki.debian.org/Teams/Ruby
contact point: [e-mail]
IRC: #debian-ruby @ irc.debian.org

- Lucas (for the Debian Ruby team)