I don't see how the second alternative of the || could ever be false (i.e. the coverage would never be 100%).
It can't, but just like with xdg's note about my $value = $some_other_value || undef;, Devel::Cover is also smart enough to realize that DEFAULT_FILENAME is a constant and removes the truth table entries of it being false, so that you can get to 100% coverage for that line.

In reply to Re^4: TDD with Coverage Analysis. Wow. by davidrw
in thread TDD with Coverage Analysis. Wow. by dws

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