Thats much better than current code. At least it doesnt try to set an array to a fieldset. But it is still giving me errors. Also this test isnt passing #5495

For some reason, when dealing with nested fieldsets, you must to add a new Hydrator to then on the "mainFieldset" after adding it (even if in the target Fieldset you already add one):

on "mainFieldset":

    $this->add(array(
        'type' => 'Zend\Form\Element\Collection',
        'name' => 'specifications',
        'options' => array(
            'label' => 'Option specifications',
            'count' => 1,
            'allow_add' => true,
            'allow_remove' => true,
            'should_create_template' => true,
            'target_element' => new SpecificationFieldset($objectManager),
        ),
        'attributes' => array(
            'class' => 'nested-fieldset',
            'id' => 'opt_specifications',
        ),
    ));
    $this->get('specifications')->setHydrator(new DoctrineHydrator($objectManager));

on target Fieldset

$this->setHydrator(new DoctrineHydrator($objectManager))->setObject(new \Bundle\Entity\Specification());

Had to do that to solve my issue with nested fieldsets

That is very weird. @thestanislav, can you take a look?

I think this really should be merged asap. My nested forms are trying to bind arrays to fieldsets, which is obviouly wrong.

@thestanislav Are you still on this? Can i talk to you in #zftalk? What is your nickname?

Please add test cases