--- /dev/null
+<?php
+
+namespace Drupal\form_test\Form;
+
+use Drupal\Core\Form\FormBase;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Builds a form to test the required attribute.
+ */
+class FormTestRequiredAttributeForm extends FormBase {
+
+ /**
+ * {@inheritdoc}
+ */
+ public function getFormId() {
+ return 'form_test_required_attribute';
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function buildForm(array $form, FormStateInterface $form_state) {
+ foreach (['textfield', 'textarea', 'password'] as $type) {
+ $form[$type] = [
+ '#type' => $type,
+ '#required' => TRUE,
+ '#title' => $type,
+ ];
+ }
+ $form['submit'] = [
+ '#type' => 'submit',
+ '#value' => 'Submit',
+ ];
+ return $form;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function submitForm(array &$form, FormStateInterface $form_state) {
+ }
+
+}