Test coverage using Devel::Cover
cover --test
Once we know that our tests are passing we could check which lines are exercised in the code during the test execution. For this we can use Devel::Cover by Paul Johnson. First we need to run the tests again now instrumenting with Devel::Cover. This will be much slower than the regular execution but in the end we will get a text report and we will be able to build a nice HTML report with drill down about all the code we ran.

All tests successful.
Files=11, Tests=2078, 50 wallclock secs
- Devel::Cover.
- CPAN Cover generates and collects the test coverage report of modules recently uploaded to CPAN.
- Meta::CPAN includes the test-coverage report of most of the modules.