public function attachEntityFields(EntityInterface $entity)
    {
        $_fields = [];
        foreach ($this->_attributesForEntity($entity) as $attr) {
            $field = $this->_prepareMockField($entity, $attr);
            if ($entity->has($field->get('name'))) {
                $this->_fetchPost($field);
            }

            $field->fieldAttached();
            $_fields[] = $field;
        }

        $entity->set('_fields', new FieldCollection($_fields));

        return $entity;
    }