The module tests are run by *.t files in the t directory. But once you
have 'make'd the module, you can try these commands to see what
Test::Usage output actually looks like:

    perl -Mblib -It -MM1_T -e test
    perl -Mblib -It -MM2_T -e test
    perl -Mblib -It -MM2_T -e 'test(c => 0)'

    perl -Mblib -It -MFoo_T -e test
    perl -Mblib -It -MFoo_T -e 'test(v => 0)'
    perl -Mblib -It -MFoo_T -e 'test(v => 2)'
    perl -Mblib -It -MFoo_T -e 'test(f => 1)'

    perl -Mblib -MTest::Usage -e 'files(d => "t", i => "t")'

        # These must be run from the 't' directory.
    perl -Mblib -MTest::Usage -e files
    perl -Mblib -MTest::Usage -e 'files(t => {v => 2, c => 0})'