24     'class' => 
'upgrade-data hidden',
 
   31     $count === Batch::UNKNOWN_COUNT ? 
'0/???' : 
"0/{$count}" 
   35     'class' => 
'elgg-progressbar',
 
   39     'href' => 
"#upgrade-errors-{$entity->guid}",
 
   40     'text' => 
elgg_echo(
'upgrade:error_count', [0]),
 
   41     'class' => [
'elgg-toggle', 
'upgrade-error-counter'],
 
   45     'id' => 
"upgrade-errors-{$entity->guid}",
 
   46     'class' => 
'upgrade-messages elgg-message elgg-state-error hidden',
 
   51     'title' => 
$entity->getDisplayName(),
 
Represents an upgrade that runs outside of the upgrade.php script.
Long running upgrades should implement this interface.
elgg_extract($key, $array, $default=null, bool $strict=true)
Checks for $array[$key] and returns its value if it exists, else returns $default.
elgg_echo(string $message_key, array $args=[], string $language='')
Elgg language module Functions to manage language and translations.
elgg_view(string $view, array $vars=[], string $viewtype='')
Return a parsed view.
elgg_format_element(string $tag_name, array $attributes=[], string $text='', array $options=[])
Format an HTML element.
if(! $batch|| $batch->shouldBeSkipped()) $count
if(! $entity instanceof ElggUpgrade) $batch