I'm not sure it's my top 3 but a quick skim of bookmarks found these more perl-specific items:

• Extreme Perl

• Test driven development with Perl and vim

• Test Driven Development (Grant McLean)

Maybe not TDD per se', but Perl Testing: A Developer's Notebook is a good read.

update: Well ... yes per se'.

We wrote almost everything in there with TDD in mind, actually.

We wrote almost everything in there with TDD in mind, actually.

But there is very little in there about the actual process of TDD (triangulation, fake-it-till-you-make-it, etc.). It's not even mentioned in the index :-)

Loads of useful info on how to use a bunch of great tools of course. It is an excellent book! Just not something I'd give to somebody who wanted to learn how to do TDD.

For that I would personally recommend:

• Test Driven Development: By Example - some folk find this too simplistic, but I personally find that there's a lot of power in those simple examples.
• Test Driven Development: A Practical Guide - the one that most folk who dislike Beck's TDD: By Example seem to like. I like it too - but prefer the TDD: By Example
• Extreme Programming Adventures in C# - yes an MS press book about C#. Still has some darn fine examples of using TDD in practice.

I can also heartily recommend Perl Testing: A Developer's Notebook as a practical hands-on guide to TDD with Perl. It skimps somewhat on the "general methodology" stuff but that's just the type of book it is, light on theory, heavy on practice.

For a slightly more fundamental and verbose approach you could try Test Driven Development By Example by Kent Beck. The code in that book is all Java, but it's easy enough to extrapolate to Perl from that.

And testdriven.com is a good resource of news in this area (if also rather Java-heavy).

Also, check out chromatics "Refactoring Everything" series of articles. While not nominally about TDD it contains grains,gems and boulders of wisdom on the subject.

In addition to the books I mentioned I'd also recommend joining the agile-testing and testdrivendevelopment mailing lists.