Form element "checkboxes" with "required" fails validation if all selected options are disabled

Hello.

I'm asking for the community's help again because I think there is a bug in drupal core with the form #state API.

Specifically, checkboxes and lists are not activated as required by form #state.

In the case of checkboxes, the requirement asterisk is not added, but required="required" and aria-required="true" attribute are added, but the checkboxes do not become required.

The same is with the lists except that the asterisk is added, but it is not required either.

I have a list, which I use with the checkbox/radio widget, which is the master.

And I also use the other slave list with the checkbox/radio widget, I have controlled the visibility and the requirement with form #state.

When I choose a value or checkbox from the master list the slave list becomes visible and should be and required.

And the requirement doesn't work, an visibility working well.

I read a lot about this bug, since the drupal 7 version it is not well fixed.

If someone can give me some solution.

Thanks for help.

/**
 * Implements hook_form_BASE_FORM_ID_alter() for node form.
 */
function buangh_mantenimiento_diario_piscina_form_node_form_alter(&$form, FormStateInterface $form_state, $form_id): void {
  $node = $form_state->getFormObject()->getEntity();
  if ($node->getType() !== 'mantenimiento_diario_piscina') {
    return;
  }

// field hide/view
$form['field_operacion_filtro_mantenimi']['#states'] = [
  'visible' => [
    ':input[name^="field_operacion_de_mantenimiento[Limpieza del filtro]"]' => ['checked' => TRUE],
  ],
];
// field required
$form['field_operacion_filtro_mantenimi']['widget']['#states'] = [
  'required' => [
    ':input[name^="field_operacion_de_mantenimiento[Limpieza del filtro]"]' => ['checked' => TRUE],
  ],
];

}

Did you try the patch on this ticket?

For #26.

To see if a better solution can be had.

rebased for 10.1.1

Re #26, this doesn't seem to be a problem at the checkbox level. This form works and passes validation:

    $form['test-3293609'] = [
      '#type' => 'checkbox',
      '#title' => 'test 3293609',
      '#default_value' => TRUE,
      '#disabled' => TRUE,
      '#required' => TRUE,
    ];

    $form['submit'] = [
      '#type' => 'submit',
      '#value' => $this->t('Submit'),
    ];

This one with a checkboxes element fails validation:

    $form['test-3293609'] = [
      '#type' => 'checkboxes',
      '#title' => 'test 3293609',
      '#options' => [
        'alpha' => 'Alpha',
        'beta' => 'Beta',
      ],
      '#default_value' => [
        'alpha' => 'alpha',
      ],
      '#required' => TRUE,
    ];
    $form['test-3293609']['alpha']['#disabled'] = TRUE;

    $form['submit'] = [
      '#type' => 'submit',
      '#value' => $this->t('Submit'),
    ];