Fixed Nondeterministic sorting during code extension, code event listener and template modification rebuilds

[Xon]

Affected version

2.1.17

When the execution order for a code extension or code event listener is the same, potential nondeterministic sorting between XF installs;

public function getExtensionCacheData()
{
   $extensions = $this->finder('XF:ClassExtension')
      ->whereAddOnActive(['disableProcessing' => true])
      ->where('active', 1)
      ->order(['execute_order'])
      ->fetch();
...

public function getListenerCacheData()
{
   $listeners = $this->finder('XF:CodeEventListener')
      ->whereAddOnActive(['disableProcessing' => true])
      ->where('active', 1)
      ->order(['event_id', 'execute_order'])
      ->fetch();

   $cache = [];
...

public function applyModificationsToTemplate($type, $title, $template, &$status = [])
{
   $modifications = $this->finder('XF:TemplateModification')
      ->where([
         'type' => $type,
         'template' => $title,
         'enabled' => 1
      ])
      ->whereAddOnActive()
      ->order('execution_order')
      ->fetch();
...

If execute_order/execution_order has duplicate values, what happens is the rows with duplicate values tend to be sorted by the primary id which is a proxy for install order. However the sorting by primary id isn't guaranteed, and is different across installs.

This means the interaction between various add-ons can be non-deterministic depending on the install order, which is a very unexpected experience.

Especially as these don't match findTemplateModificationsForList, findExtensionsForList, findListenersForList sorting behaviour.

findExtensionsForList should probably include execution_order in it's sort.

 

[XF Bug Bot]

Thank you for reporting this issue, it has now been resolved. We are aiming to include any changes that have been made in a future XF release (2.1.8).

Change log:

Ensure more consistent sorting is used for class extensions, code event listeners and template modifications.

There may be a delay before changes are rolled out to the XenForo Community.