FormTestRangeInvalidForm.php

<?php

namespace Drupal\form_test\Form;

use Drupal\Core\Form\FormBase;
use Drupal\Core\Form\FormStateInterface;

/**
 * Form constructor for testing invalid #type 'range' elements.
 *
 * @internal
 */
class FormTestRangeInvalidForm extends FormBase {
    
    /**
     * {@inheritdoc}
     */
    public function getFormId() {
        return 'form_test_range_invalid';
    }
    
    /**
     * {@inheritdoc}
     */
    public function buildForm(array $form, FormStateInterface $form_state) {
        $form['minmax'] = [
            '#type' => 'range',
            '#min' => 10,
            '#max' => 5,
            '#title' => 'Invalid range',
            '#description' => 'Minimum greater than maximum.',
        ];
        $form['submit'] = [
            '#type' => 'submit',
            '#value' => 'Submit',
        ];
        return $form;
    }
    
    /**
     * {@inheritdoc}
     */
    public function submitForm(array &$form, FormStateInterface $form_state) {
    }

}