MooseX::GetOpt should include Test::Moose as a test_requires.
While Test::Moose is indeed bundled with Moose, some distributions
(e.g. Fedora) split test modules out into distinct sub-packages to
reduce the number of dependencies installed for those simply wanting
to run a program that needs the module, rather than test/develop Perl.
As such, Test::Moose is in its own subpackage and a dependency on Moose
does not cause it to be installed as well.
Adding Test::Moose as a test_requires will make it easier for automated
packaging / build tools to package (and update!) this module.
Thanks! :)