Perl's testing framework doesn't actually require in any way that the thing being tested is perl. There's a reasonably well-defined protocol that governs what the test outputs, all you need is some code to output that, and it doesn't matter the code that outputs it is perl, C, python, or brainf*ck. There's a fairly good article on the Test Anything Protocol on WP, or just run any existing test with perl -Mblib t/foo.pl and observe what it outputs.