Dynamic validation groups

form.php

<?php
    // form skipped for brevity

    public function configureOptions(OptionsResolver $resolver)
    {
        $resolver->setDefaults(array(
            'validation_groups' => function (FormInterface $form) {
                return $form->getConfig()->getOption('option_name') ?
                    ['group1', 'group2'],
                    ['group3'];
            },
        ));
    }