Good point; part of why I eschew chdir style code. A little more on your call out–

package AB; # File: /Users/moo/AB.pm
use strict;
use Path::Tiny;
sub ohai { __FILE__ }
sub ohai_der { path(__FILE__)->absolute }
1;
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moo@cow[54]~>perl -MAB -le 'print AB->ohai; print AB->ohai_der'
AB.pm
/Users/moo/AB.pm
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moo@cow[55]~>perl -MAB -le 'chdir "/tmp"; print AB->ohai; print AB->oh
+ai_der;'
AB.pm
/private/tmp/AB.pm
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