Some code coverage (unit test coverage) tools:

EMMA – open source

Cobertura – open source

Clover – Atlassian

Hansel & Gretel – only found info on an IBM developerworks article

Quilt – open source

Jester – open source

Jester takes a very interesting approach. It actually changes to code and then sees if your tests break. For instance it might change: if (x>y) to if (false)

All of the above target Java. What about for other languages like Perl, PHP, Python, and Ruby? What about for Smalltalk?

PHPCoverage – Spikesource

(here is an interesting list of tools for PHP)

rcov – for Ruby

http://www.semdesigns.com/products/testcoverage/PHPTestCoverage.html

heckle is a Ruby version of Jester.  Link here. Another link to an article on heckle

Of course there’s controversy about the value of code coverage tools, but really it’s an issue of misusing them. They are useful, and they give people something to aim for. A more interesting idea is a “functionality” coverage tool — which would have to be more manually built. An interesting article mentions rspec but that’s not really what I meant, though still an interesting idea.

A requirements coverage matrix shouldn’t be a crutch any more than a code coverage report, but the combination could be powerful.