block_theme_suggestions_block

block_theme_suggestions_block(array $variables)

function block_theme_suggestions_block(array $variables) {
  $suggestions = array();

  $suggestions[] = 'block__' . $variables['elements']['#configuration']['provider'];
  // Hyphens (-) and underscores (_) play a special role in theme suggestions.
  // Theme suggestions should only contain underscores, because within
  // drupal_find_theme_templates(), underscores are converted to hyphens to
  // match template file names, and then converted back to underscores to match
  // pre-processing and other function names. So if your theme suggestion
  // contains a hyphen, it will end up as an underscore after this conversion,
  // and your function names won't be recognized. So, we need to convert
  // hyphens to underscores in block deltas for the theme suggestions.

  // We can safely explode on : because we know the Block plugin type manager
  // enforces that delimiter for all derivatives.
  $parts = explode(':', $variables['elements']['#plugin_id']);
  $suggestion = 'block';
  while ($part = array_shift($parts)) {
    $suggestions[] = $suggestion .= '__' . strtr($part, '-', '_');
  }

  if (!empty($variables['elements']['#id'])) {
    $suggestions[] = 'block__' . $variables['elements']['#id'];
  }

  return $suggestions;
}