node_access_view_all_nodes example

  protected function checkNodeGrants($operation) {
    // When checking the grants for the 'view' operation and the current user     // has a global view grant (i.e. a view grant for node ID 0) — note that     // this is automatically the case if no node access modules exist (no     // hook_node_grants() implementations) then we don't need to determine the     // exact node view grants for the current user.     if ($operation === 'view' && node_access_view_all_nodes($this->user)) {
      return 'view.all';
    }

    $grants = node_access_grants($operation, $this->user);
    $grants_context_parts = [];
    foreach ($grants as $realm => $gids) {
      $grants_context_parts[] = $realm . ':' . implode(',', $gids);
    }
    return $operation . '.' . implode(';', $grants_context_parts);
  }