LdapTools\Object\LdapObject::add PHP Method

    public function add($attribute, ...$values)
    {
        foreach ($values as $value) {
            if ($this->has($attribute)) {
                $attribute = $this->resolveAttributeName($attribute);
                $this->attributes[$attribute] = $this->addAttributeValue($this->attributes[$attribute], $value);
            } else {
                $this->attributes[$attribute] = $value;
            }
            $this->batches->add(new Batch(Batch::TYPE['ADD'], $attribute, $value));
        }
        return $this;
    }

 function it_should_hydrate_a_ldap_object_wihtout_a_schema_with_batch_modification()
 {
     $ldapObject = new LdapObject(['dn' => 'cn=foo,dc=foo,dc=bar'], [], 'user', '');
     $ldapObject->set('givenName', 'Chad');
     $ldapObject->add('sn', 'Sikorra');
     $ldapObject->remove('sAMAccountName', 'csikorra');
     $ldapObject->reset('mail');
     $this->hydrateToLdap($ldapObject)->shouldBeEqualTo($this->batch);
     $this->hydrateToLdap($ldapObject)->shouldHaveCount(4);
 }