Collection attempts to access object property on $this->targetElement

[erispre]

This issue applies to Zend\Form\Element\Collection. When setting the target element of the collection, a Zend\Form\ElementInterface is expected (on Collection::setTargetElement()). This promotes the use of regular form elements, like Zend\Form\Element\Text to be used as a target element.

However, when using e.g. Text as a target element, binding an ArrayObject with a few values set and setting no hydrator, the Collection::extract() method attempts to access $this->targetElement->object, which is only defined if $this->targetElement is a Zend\Form\Fieldset. To clarify, consider the following test case:

$form = new \Zend\Form\Form('test');
$text = new \Zend\Form\Element\Text('text');
$form->add(array(
    'name' => 'text',
    'type' => 'Zend\Form\Element\Collection',
    'options' => array(
        'target_element' => $text, 'count' => 2,
    ),
));
$object = new \ArrayObject(array('text' => array('Foo', 'Bar')));
$form->bind($object);

This case will trigger a fatal error.

I suggest to add a check on whether $this->targetElement is a Fieldset and when everything fails just copying the value, assuming no hydration is needed. I am submitting a patch soon.

[erispre]

It has come to my attention that the same issue appears in one of the unit tests of Collection. These tests seem to call $targetElement->setObject(), which is not defined by Zend\Form\ElementInterface.

[adamlundrigan]

Duplicate of #4482 ?

[SteveTalbot]

Related to #4482, but not a duplicate.

I've just created pull request #6518 containing our workaround for this.

[Ocramius]

Fixed via #6880, thanks!