The method isEmpty checks the input form data. It checks for simple nullable elements, empty strings, empty arrays and empty traversables. Am i wrong? If i have an object, which consist only of empty collections, nullable fields etc., shouldn't it check such an 'empty' object and return true aswell?

Following use case: I have an embedded collection in an entity form. It's attributes have some asserts (notnull, empty, etc.). Adding and Removing with prototype works perfectly, but if i just add a new entry and enter nothing, it should delete the entry on submit with the flag delete_empty. Actually, it does not, because modelData is an object, therefore not empty and the standard validation errors occur.

Current isEmpty method:

    public function isEmpty()
    {
        foreach ($this->children as $child) {
            if (!$child->isEmpty()) {
                return false;
            }
        }

        return FormUtil::isEmpty($this->modelData) ||
            // arrays, countables
            0 === count($this->modelData) ||
            // traversables that are not countable
            ($this->modelData instanceof \Traversable && 0 === iterator_count($this->modelData));
    }

My idea would be, to additionally check if modelData is an object and if the object has a self made isEmpty method. (A generic version is also possible - all getter)
(is_object($this->modelData) && method_exists($this->modelData, 'isEmpty') && call_user_func(array($this->modelData, 'isEmpty')))

Best regards,
Nino