How to write unit test cases for a Perl script

I'm able to write unit tests test_case.t for a Perl Module ModuleOne.pm

test_case.t

use strict;
use warnings;
use Test::More;
use Test::Cmd;
use ModuleOne; # Included the module here

my $ret = ModuleOne::methodone(args);
is($ret->{val}, 1, "Checking return value"); # success 

I'm trying the achieve the same unit test cases for a perl script script_one.pl

script_one.pl

use strict;
use warnings;
use ModuleOne;

my $NAME;
my $ID;

# get parameters
GetOptions (
 "name" => \$NAME,
 "emp_id" => \$ID,
)

validate_params();

sub validate_params {
   # this method will validate params 
}

sub print_name {
   # this method will print name 
}

How can I include this perl file script_one.pl in test_case.t and write test cases for methods validate_params and print_name?