Any language would be improved if it had Perl's testing and library culture. Two things it's absolute unsurpassed at so far.
Does ruby not have the same level of both?
CPAN has had many more years than Ruby's Gems to mature and develop.
There are 2560 [edit: I was wrong. 39411 is the right number] gems on http://rubygems.org/. There are 24,920 distributions on CPAN. Well over 100k modules. The automated testing infrastructure, documentation, etc. also makes it much easier to figure out what modules work on what systems and what versions of perl than in ruby land. Things like meta.cpan.org and cpantesters.org are a god send that I wish I had when I'm using other languages.
And the testing infrastructure rocks.
It's evolved so everything produces and consumes TAP (http://testanything.org/) a simple human-readable protocol for expressing pass/fail results (with standard modules that help people output and consume TAP).
This means I can write tests procedurally, or in an xUnit style, or a BDD style, or a specification-based testing style, or use various DSLs for things like exception testing or for testing web apps... and so on.
I just use the style that seems most appropriate for the thing being tested. They all output TAP. All the standard test runners consume TAP. Everything "just works" and plays nice together.
I can even easily integrate tests running in other languages or environments as long as they output TAP.
In addition - since almost all of the Perl testing modules use a common TAP output module - you can usually integrate different styles in the same test code. So, if appropriate, I can pop some specification-based tests and some friendly web-testing DSL as assertions inside my xUnit tests.
Fun :-)
Wish other languages test environments were setup this way.