My instinct suggests that this is in fact “a poorly-written test,” which if so ought to be reported as a possible bug/issue in that package.
The relevant piece of code appears to be this:
Dubious, test returned 255 (wstat 65280, 0xff00)
and, in order to really find out what is going on, you will need to locate that .tt
is your friend ...) and eyeball it to see what the test is trying to do and whether it actually matters. Why is it calling wstat
? What does 0xff00
mean, and what is the test actually testing-for? And so on.
Maybe it does matter, maybe it doesn’t. (The test result was called “dubious ...”) If you conclude that it is an inappropriate or incorrect test, and since this is apparently the only test that failed, the use of --force might be appropriate as a workaround. (And should be reported as a bug, tagged to your particular environment.)
You can also look at the CPANTS environment-test results, which are accessible from the CPAN page, to determine if this issue is known to exist on your particular operating-system and version. Although authors may not be able to “test their code everywhere,” that basically is what CPANTS does.