throw an exception when IDs passed to loadMultiple() are badly formed

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Edge-case:

I have 0, 1 or 2 entities to load and the order matters in my case.
For performance reasons I want to load them `loadMultiple()`

$nodeIds = [
  $queryPrev->execute()->fetchField(),
  $queryNext->execute()->fetchField(),
];
$nodes = $this->entityTypeManager->getStorage('node')->loadMultiple($nodeIds);
return [
  '#prev' => !empty($nodes[$nodeIds[0]]) ? $nodes[$nodeIds[0]] : NULL,
  '#next' => !empty($nodes[$nodeIds[1]]) ? $nodes[$nodeIds[1]] : NULL,
];

To avoid the warning you need extensive logic. E.g:

if (count(array_filter($nodeIds)) === 2) {
  $nodes = $this->entityTypeManager->getStorage('node')->loadMultiple($nodeIds);
}
elseif (!empty($nodeIds[0])) {
  $nodes = [
    $this->entityTypeManager->getStorage('node')->load($nodeIds[0]),
    NULL,
  ];
}
elseif (!empty($nodeIds[1])) {
  $nodes = [
    NULL,
    $this->entityTypeManager->getStorage('node')->load($nodeIds[1]),
  ];
}

But if you would have 3, 4, 5 entities to load multiple single loads would be needed.

I'm not demanding changes, just wanted to point out to this DX