https://api.drupal.org/api/drupal/core%21modules%21system%21tests%21modules%21form_test%21src%21Form%21FormTestValidateRequiredForm.php/class/FormTestValidateRequiredForm/10
class FormTestValidateRequiredForm | Drupal API
classdrupalapi
https://api.drupal.org/api/drupal/core%21modules%21system%21tests%21modules%21form_test%21src%21Form%21FormTestValidateRequiredForm.php/function/FormTestValidateRequiredForm%3A%3AsubmitForm/9
function FormTestValidateRequiredForm::submitForm | Drupal API
functiondrupalapi