$ perl -MFile::Basename -wE 'say basename("foo.psd",".psd")'
foo

##</code><code>##

$ perl -MFile::Basename -wE 'say basename(undef,".psd")'
Use of uninitialized value $_[0] in substitution (s///) at /Users/1nickt/perl5/perlbrew/perls/perl-5.30.0/lib/5.30.0/File/Basename.pm line 341.
fileparse(): need a valid pathname at -e line 1.