| Subject: | process_PL_files does not execute PL file when $to is empty list. |
Consider the case where
PL_files => { 'lib/My/Special.pm.PL' => [], },
The expected behavior is that Module::Build::Base::process_PL_files()
will execute lib/My/Special.pm.PL but not add anything to _build/cleanup
not _build/build_params.
But, lib/My/Special.pm.PL does not get executed.
This seems to be because Module::Build::Base::up_to_date returns true
when @$derived is empty.
up_to_date() takes two arguments: $source and $derived
If the second argument is empty then up_do_date returns true, which is
probably wrong. Instead, I think up_to_date() should return false if
@$derived is empty.