How to set translation domain for custom errors in form validators?

Question

symfony

There is a regular form (a Symfony Forms component) with some fields and a custom translation domain is configured for them. The standard rules from Symfony Validation apply to the fields.
Question: how can I set a custom translation domain to translate validator error messages? You can add translations to the validators.en.yml file , but what I really need is to be able to specify the necessary translation domain for different forms.
Form example (shortened):

class RegistrationForm extends AbstractType
{
    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder
            ->add('login', TextType::class, [
                'label' => 'registration.details.label.login',
                'constraints' => [
                    new NotBlank(['message' => 'registration.details.error.login.required']),
                    new Regex([
                        'pattern' => '/^[a-z0-9_]+/i',
                        'message' => 'registration.details.error.login.wrong_symbols'
                    ]),
                ],
            ])
            ...
    }

    public function configureOptions(OptionsResolver $resolver)
    {
        // Set custom translation domain for this form
        $resolver->setDefaults(['translation_domain' => 'users']);
    }

    public function getExtendedType()
    {
        return FormType::class;
    }
}

Answer 1

Some strange "standard" form type. It doesn't seem to have a getExtendedType() method...
As for validation.
Use validation groups, the form will be cleaner, and the validation object will be available in the context of the validator.
In setDefaults , you have a default value, so to change the domain in another form that reuses this type, you just need to override this value.

$this->createForm(RegistrationForm:class, null, ['translation_domain' => 'foo'])
$this->createForm(RegistrationForm:class, null, ['translation_domain' => 'bar'])