How on node forms do I show weight of all menu items?

Question

I'm wondering how it is possible (with a hook) to show the weight next to the menu title in the parent drop down found in the Menu Settings tab.

So this is what it is at this moment:

And this is what I want it to be, so the admin knows what weight to fill in to place the menu item at a certain place:

Answer 1

Doing a hook_form_alter on the node edit form should do the trick:

  use Drupal\Core\Form\FormStateInterface;

  function MYMODULE_form_alter(&$form, FormStateInterface $form_state, $form_id) {
  /** to appear on the node/add/page form, change this or add more for other content types **/
  if ($form_id == 'node_page_form') {
    $menuItems = $form['menu']['link']['menu_parent']['#options'];
    $menuItemsWithWeight = array();
    foreach ($menuItems as $menuKey => $menuValue) {
      $storage =  Drupal::entityManager()->getStorage('menu_link_content');
      $uuid = ltrim(strstr($menuKey, ':'), ':');
      $uuid = ltrim(strstr($uuid, ':'), ':');
      $link = $storage->loadByProperties(['uuid' => $uuid]);
      if(count($link) > 0) {
        $link = reset($link);
        $weight = $link->getWeight();
        $menuValue = $menuValue . ' ('.$weight.')';
      }
      $menuItemsWithWeight[$menuKey] = $menuValue;
    }
    $form['menu']['link']['menu_parent']['#options'] = $menuItemsWithWeight;
   }
  }