AccessResult::andIf

public AccessResult::andIf(AccessResultInterface $other)

  |A N F
--+-----
A |A N F
N |N N F
F |F F F

public function andIf(AccessResultInterface $other) {
  // The other access result's cacheability metadata is merged if $merge_other
  // gets set to TRUE. It gets set to TRUE in one case: if the other access
  // result is used.
  $merge_other = FALSE;
  if ($this->isForbidden() || $other->isForbidden()) {
    $result = static::forbidden();
    if (!$this->isForbidden()) {
      if ($other instanceof AccessResultReasonInterface) {
        $result->setReason($other->getReason());
      }
      $merge_other = TRUE;
    }
    else {
      if ($this instanceof AccessResultReasonInterface) {
        $result->setReason($this->getReason());
      }
    }
  }
  elseif ($this->isAllowed() && $other->isAllowed()) {
    $result = static::allowed();
    $merge_other = TRUE;
  }
  else {
    $result = static::neutral();
    if (!$this->isNeutral()) {
      $merge_other = TRUE;
    }
  }
  $result->inheritCacheability($this);
  if ($merge_other) {
    $result->inheritCacheability($other);
    // If this access result is not cacheable, then an AND with another access
    // result must also not be cacheable, except if the other access result
    // has isForbidden() === TRUE. isForbidden() access results are contagious
    // in that they propagate regardless of the other value.
    if ($this->getCacheMaxAge() === 0 && !$result->isForbidden()) {
      $result->setCacheMaxAge(0);
    }
  }
  return $result;
}