use Modern::Perl;
use File::Find::Rule;

my $directory   = 'c:/data/strawberry-perl/perl/script-chrome';
my $dir_pattern = 'test_';

my $next = (
            sort { $b <=> $a }
            map  { /(\d+)$/; $1 }
            File::Find::Rule->directory
                            ->name( "$dir_pattern*" )
                            ->in( $directory )
           )[0] + 1;

mkdir "$directory/$dir_pattern$next", 0755 or die "Could not make directory $directory/$dir_pattern$next";