ProcessWire duplicate role with permissions and field access

processwire-duplicate-role.php

<?php namespace ProcessWire;

include('index.php');

$contractingRole = wire('roles')->get('contracting-user');
$managerRole = wire('roles')->get('manager');
$managerRole->of(false);
$managerRole->permissions = $contractingRole->permissions;
$managerRole->save();

foreach (wire('fields') as $f) {

    if (in_array($contractingRole->id, $f->viewRoles)) {

        $array = $f->viewRoles;
        $array[] = $managerRole->id;
        $f->viewRoles = $array;
        $f->save();
    }
    echo $f->name;
    echo "<hr>";
}