ZF2 Fieldset rendering: name parameter is not set correctly in forms

[catilgan]

I am rendering a Zf2 form which contains a fieldset as a child element (simplified for this ticket):

class RegistrationForm extends Form
{
    public function __construct($name = "company_registration_form", array $options = [])
    {
         parent::__construct($name, $options);

         $user = new UserFieldset('user');
         $this->add($user);

        $this->setValidationGroup([
            'user' => [
                'nameFirst',
            ],
        ]);
    }
}

The fieldset is defined as following:

class UserFieldset extends Fieldset implements InputFilterProviderInterface
{
    public function __construct($name = 'user', $options = [])
    {
        parent::__construct($name, $options);

        $this->add([
            'name' => 'nameFirst',
            'type' => 'Zend\Form\Element\Text',
            'required' => false,
            'options' => [
                'label' => _('Vorname'),
                'label_attributes' => [
                    'class' => 'left inline'
                ],
            ],
            'attributes' => [
                'class' => 'left',
            ],
        ]);
}

And at last the twig template used for rendering the form:

{{ form().prepare() }}
{{ form().openTag(form)|raw }}

{{ formLabel(form.get('user').get('nameFirst'))|raw }}
{{ formInput(form.get('user').get('nameFirst')) }}

{{ form().closeTag(form)|raw }}

The HTML output looks like this:

<form id="company_registration_form" data-abide="" name="company_registration_form" method="post" novalidate="novalidate">
  <label for="nameFirst" class="left inline">Vorname</label>
  <input type="text" value="" class="left" name="nameFirst" aria-invalid="false">
</form>

As you can see, the name parameter is not correctly set. It should be name="user[nameFirst]", instead of the plain field name. When i render the same form with .phtml (no changes made to forms) the name value is set correctly.

Therefore, i assume that the view helper handles the fieldset differently in case of twig templates. Could you please give me any directions how to fix this issue? Is this a bug or am I rendering the template incorrectly.

Many thanks for the answers.

Our composer.json looks like this:

{
    "require": {
        "zendframework/zendframework": "2.5.1",
        "doctrine/doctrine-orm-module": "0.9.1",
        "zf-commons/zfc-twig": "1.2.2",
        "zf-commons/zfc-user": "1.2.2",
        "zf-commons/zfc-user-doctrine-orm": "1.0.1",
        "bjyoungblood/bjy-authorize": "1.4.0",
        "gedmo/doctrine-extensions": "v2.4.4",
        "twig/extensions": "v1.2.0"
    }
}

[Alfredao]

Had you find a solution? I have the same problem here