I am using Active State Perl and only have the version of File-Util that "works", 4.132140. I did verify that your code works with this version. 
#!/usr/bin/perl 
use strict; 
use warnings;

# Using Active State Perl 5.20.2

use File::Util;  #version 4.132140
my $f = File::Util->new(); 
my @d = $f->list_dir("C:/test"); 
print join " ", @d, "\n";

__END__
. .. anothertestdir bar bar2

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From test code and docs, this code does what is supposed to do (with no actual "simple file", returns the dot directories + others). If a later version of Util::File is throwing an internal error as your post indicates, then I would consider that a bug. Forcing installation of a "non-approved" AS repository module version is a mess that I really don't want to attempt.

Update: From looking at next responses, it does appear that this is a legit bug report and I would recommend proceeding with that.

In reply to Re: Bug in latest File::Util? by Marshall
in thread Bug in latest File::Util? by martell

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