public function BubbleableMetadata::merge

Creates a new bubbleable metadata object by merging this one with another.

Parameters

\Drupal\Core\Cache\CacheableMetadata $other: The other bubbleable metadata object.

Return value

static A new bubbleable metadata object, with the merged data.

Overrides CacheableMetadata::merge

File

core/lib/Drupal/Core/Render/BubbleableMetadata.php, line 26

Class

BubbleableMetadata

Value object used for bubbleable rendering metadata.

Namespace

Code

public function merge(CacheableMetadata $other) {
  $result = parent::merge($other);

  // This is called many times per request, so avoid merging unless absolutely
  // necessary.
  if ($other instanceof BubbleableMetadata) {
    if (empty($this->attachments)) {
      $result->attachments = $other->attachments;
    }
    elseif (empty($other->attachments)) {
      $result->attachments = $this->attachments;
    }
    else {
      $result->attachments = static::mergeAttachments($this->attachments, $other->attachments);
    }
  }
  return $result;
}