[6.1] Make abstract immutable event actually immutable

administrator/components/com_content/src/Model/ArticleModel.php

@@ -11,7 +11,7 @@
 namespace Joomla\Component\Content\Administrator\Model;
 
 use Joomla\CMS\Date\Date;
-use Joomla\CMS\Event\AbstractEvent;
+use Joomla\CMS\Event\EventFactory;
 use Joomla\CMS\Factory;
 use Joomla\CMS\Filter\InputFilter;
 use Joomla\CMS\Form\Form;
@@ -843,7 +843,7 @@ public function featured($pks, $value = 0, $featuredUp = null, $featuredDown = n
         // Trigger the before change state event.
         $eventResult = Factory::getApplication()->getDispatcher()->dispatch(
             $this->event_before_change_featured,
-            AbstractEvent::create(
+            EventFactory::create(
                 $this->event_before_change_featured,
                 [
                     'eventClass' => FeatureEvent::class,
@@ -948,7 +948,7 @@ public function featured($pks, $value = 0, $featuredUp = null, $featuredDown = n
         // Trigger the change state event.
         Factory::getApplication()->getDispatcher()->dispatch(
             $this->event_after_change_featured,
-            AbstractEvent::create(
+            EventFactory::create(
                 $this->event_after_change_featured,
                 [
                     'eventClass' => FeatureEvent::class,

administrator/components/com_scheduler/src/Helper/SchedulerHelper.php

@@ -11,7 +11,7 @@
 namespace Joomla\Component\Scheduler\Administrator\Helper;
 
 use Joomla\CMS\Application\AdministratorApplication;
-use Joomla\CMS\Event\AbstractEvent;
+use Joomla\CMS\Event\EventFactory;
 use Joomla\CMS\Factory;
 use Joomla\CMS\Plugin\PluginHelper;
 use Joomla\Component\Scheduler\Administrator\Task\TaskOptions;
@@ -53,7 +53,7 @@ public static function getTaskOptions(): TaskOptions
         /** @var  AdministratorApplication $app */
         $app     = Factory::getApplication();
         $options = new TaskOptions();
-        $event   = AbstractEvent::create(
+        $event   = EventFactory::create(
             'onTaskOptionsList',
             [
                 'subject' => $options,

administrator/components/com_scheduler/src/Model/TaskModel.php

@@ -12,7 +12,7 @@
 
 use Joomla\CMS\Application\AdministratorApplication;
 use Joomla\CMS\Component\ComponentHelper;
-use Joomla\CMS\Event\AbstractEvent;
+use Joomla\CMS\Event\EventFactory;
 use Joomla\CMS\Factory;
 use Joomla\CMS\Form\Form;
 use Joomla\CMS\Form\FormFactoryInterface;
@@ -698,7 +698,7 @@ public function unlock(array &$pks): bool
             return true;
         }
 
-        $event = AbstractEvent::create(
+        $event = EventFactory::create(
             $this->event_before_unlock,
             [
                 'subject' => $this,
@@ -723,7 +723,7 @@ public function unlock(array &$pks): bool
         }
 
         // Trigger the after unlock event
-        $event = AbstractEvent::create(
+        $event = EventFactory::create(
             $this->event_unlock,
             [
                 'subject' => $this,

administrator/components/com_scheduler/src/Table/TaskTable.php

@@ -10,7 +10,7 @@
 
 namespace Joomla\Component\Scheduler\Administrator\Table;
 
-use Joomla\CMS\Event\AbstractEvent;
+use Joomla\CMS\Event\EventFactory;
 use Joomla\CMS\Factory;
 use Joomla\CMS\Language\Text;
 use Joomla\CMS\MVC\Model\AdminModel;
@@ -208,7 +208,7 @@ public function bind($src, $ignore = []): bool
     public function unlock(array $pks = [], ?int $userId = null): bool
     {
         // Pre-processing by observers
-        $event = AbstractEvent::create(
+        $event = EventFactory::create(
             'onTaskBeforeUnlock',
             [
                 'subject' => $this,
@@ -282,7 +282,7 @@ public function unlock(array $pks = [], ?int $userId = null): bool
         }
 
         // Pre-processing by observers
-        $event = AbstractEvent::create(
+        $event = EventFactory::create(
             'onTaskAfterUnlock',
             [
                 'subject' => $this,

administrator/components/com_scheduler/src/Task/Task.php

@@ -12,7 +12,7 @@
 
 use Joomla\CMS\Application\CMSApplication;
 use Joomla\CMS\Component\ComponentHelper;
-use Joomla\CMS\Event\AbstractEvent;
+use Joomla\CMS\Event\EventFactory;
 use Joomla\CMS\Factory;
 use Joomla\CMS\Language\Text;
 use Joomla\CMS\Log\Log;
@@ -211,7 +211,7 @@ public function run(): bool
         $this->snapshot['netDuration'] = 0;
 
         /** @var ExecuteTaskEvent $event */
-        $event = AbstractEvent::create(
+        $event = EventFactory::create(
             'onExecuteTask',
             [
                 'eventClass'      => ExecuteTaskEvent::class,
@@ -466,7 +466,7 @@ protected function dispatchExitEvent(): void
         $exitCode  = $this->snapshot['status'] ?? 'NA';
         $eventName = self::EVENTS_MAP[$exitCode] ?? self::EVENTS_MAP['NA'];
 
-        $event = AbstractEvent::create(
+        $event = EventFactory::create(
             $eventName,
             [
                 'subject' => $this,

administrator/modules/mod_sampledata/src/Helper/SampledataHelper.php

@@ -10,7 +10,7 @@
 
 namespace Joomla\Module\Sampledata\Administrator\Helper;
 
-use Joomla\CMS\Event\AbstractEvent;
+use Joomla\CMS\Event\EventFactory;
 use Joomla\CMS\Factory;
 use Joomla\CMS\Plugin\PluginHelper;
 
@@ -40,7 +40,7 @@ public function getSampledataList()
             ->getDispatcher()
             ->dispatch(
                 'onSampledataGetOverview',
-                AbstractEvent::create(
+                EventFactory::create(
                     'onSampledataGetOverview',
                     [
                         'subject' => new \stdClass(),

libraries/src/Event/AbstractEvent.php

@@ -25,7 +25,7 @@
  *
  * You can create a new Event with something like this:
  *
- * $event = AbstractEvent::create('onModelBeforeSomething', $myModel, $arguments);
+ * $event = \Joomla\CMS\Event\EventFactory::create('onModelBeforeSomething', $myModel, $arguments);
  *
  * You can access the subject object from your event Listener using $event['subject']. It is up to your listener to
  * determine whether it should apply its functionality against the subject.
@@ -52,7 +52,8 @@ abstract class AbstractEvent extends Event
      * @return  static
      *
      * @since   4.0.0
-     * @throws  \BadMethodCallException  If you do not provide a subject argument
+     * @throws      \BadMethodCallException  If you do not provide a subject argument
+     * @deprecated  6.0  Use \Joomla\CMS\Event\EventFactory::create instead
      */
     public static function create(string $eventName, array $arguments = [])
     {
@@ -109,7 +110,7 @@ public static function create(string $eventName, array $arguments = [])
      */
     public function __construct(string $name, array $arguments = [])
     {
-        parent::__construct($name, $arguments);
+        parent::__construct($name);
 
         foreach ($arguments as $argumentName => $value) {
             $this->setArgument($argumentName, $value);

libraries/src/Event/AbstractImmutableEvent.php

@@ -9,12 +9,17 @@
 
 namespace Joomla\CMS\Event;
 
+use Joomla\Event\AbstractEvent;
+use BadMethodCallException;
+
 // phpcs:disable PSR1.Files.SideEffects
 \defined('_JEXEC') or die;
 // phpcs:enable PSR1.Files.SideEffects
 
 /**
  * This class implements the immutable base Event object used system-wide to offer orthogonality.
+ * Note that it's implementation is very similar to \Joomla\Event\EventImmutable but it also contains the same custom
+ * setter logic for constructors as in \Joomla\CMS\Event\AbstractEvent
  *
  * @see    \Joomla\CMS\Event\AbstractEvent
  * @since  4.0.0
@@ -48,7 +53,33 @@ public function __construct(string $name, array $arguments = [])
 
         $this->constructed = true;
 
-        parent::__construct($name, $arguments);
+        parent::__construct($name);
+
+        // Same setter logic as in \Joomla\CMS\Event\AbstractEvent::setArgument
+        foreach ($arguments as $argumentName => $value) {
+            // Look for the method for the value pre-processing/validation
+            $ucfirst     = ucfirst($name);
+            $methodName1 = 'onSet' . $ucfirst;
+            $methodName2 = 'set' . $ucfirst;
+
+            if (method_exists($this, $methodName1)) {
+                $value = $this->{$methodName1}($value);
+            } elseif (method_exists($this, $methodName2)) {
+                @trigger_error(
+                    sprintf(
+                        'Use method "%s" for value pre-processing is deprecated, and will not work in Joomla 6. Use "%s" instead. Event %s',
+                        $methodName2,
+                        $methodName1,
+                        \get_class($this)
+                    ),
+                    E_USER_DEPRECATED
+                );
+
+                $value = $this->{$methodName2}($value);
+            }
+
+            $this->arguments[$argumentName] = $value;
+        }
     }
 
     /**
@@ -62,11 +93,11 @@ public function __construct(string $name, array $arguments = [])
      * @since   4.0.0
      * @throws  \BadMethodCallException
      */
-    public function offsetSet($name, $value)
+    public function offsetSet($name, mixed $value): void
     {
         // B/C check for plugins which use $event['result'] = $result;
         if ($name === 'result') {
-            parent::offsetSet($name, $value);
+            $this->arguments[$name] = $value;
 
             @trigger_error(
                 'Setting a result in an immutable event is deprecated, and will not work in Joomla 6. Event ' . $this->getName(),
@@ -95,7 +126,7 @@ public function offsetSet($name, $value)
      * @since   4.0.0
      * @throws  \BadMethodCallException
      */
-    public function offsetUnset($name)
+    public function offsetUnset($name): void
     {
         throw new \BadMethodCallException(
             sprintf(

libraries/src/Event/EventFactory.php

@@ -0,0 +1,91 @@
+<?php
+
+/**
+ * Joomla! Content Management System
+ *
+ * @copyright  (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license        GNU General Public License version 2 or later; see LICENSE
+ */
+
+namespace Joomla\CMS\Event;
+
+use Joomla\Event\Event;
+use Joomla\Event\EventInterface;
+use Joomla\String\Normalise;
+
+/**
+ * This class is a factory system that allows the creation of most core events in the Joomla Ecosystem, falling back to
+ * the creation of a \Joomla\CMS\Event\GenericEvent object for the class if no specific event class is matched. You can
+ * create a new Event with something like this:
+ *
+ * $event = EventFactory::create('onModelBeforeSomething', $myModel, $arguments);
+ *
+ * You can access the subject object from your event Listener using $event['subject']. It is up to your listener to
+ * determine whether it should apply its functionality against the subject.
+ *
+ * @since  __DEPLOY_VERSION__
+ */
+abstract class EventFactory {
+    use CoreEventAware;
+
+    /**
+     * Creates a new CMS event object for a given event name and subject. The following arguments must be given:
+     * subject      object  The subject of the event. This is the core object you are going to manipulate.
+     * eventClass   string  The Event class name. If you do not provide it Joomla\CMS\Events\<eventNameWithoutOnPrefix>
+     *                      will be used.
+     *
+     * @param   string  $eventName  The name of the event, e.g. onTableBeforeLoad
+     * @param   array   $arguments  Additional arguments to pass to the event
+     *
+     * @return  EventInterface
+     *
+     * @since   4.0.0
+     * @throws  \BadMethodCallException  If you do not provide a subject argument
+     */
+    public static function create(string $eventName, array $arguments = [])
+    {
+        // Get the class name from the arguments, if specified
+        $eventClassName = '';
+
+        if (isset($arguments['eventClass'])) {
+            $eventClassName = $arguments['eventClass'];
+
+            unset($arguments['eventClass']);
+        }
+
+        /**
+         * If the class name isn't set/found determine it from the event name, e.g. TableBeforeLoadEvent from
+         * the onTableBeforeLoad event name.
+         */
+        if (empty($eventClassName) || !class_exists($eventClassName, true)) {
+            $bareName = strpos($eventName, 'on') === 0 ? substr($eventName, 2) : $eventName;
+            $parts = Normalise::fromCamelCase($bareName, true);
+            $eventClassName = __NAMESPACE__ . '\\' . ucfirst(array_shift($parts)) . '\\';
+            $eventClassName .= implode('', $parts);
+            $eventClassName .= 'Event';
+        }
+
+        // Make sure a non-empty subject argument exists and that it is an object
+        if (!isset($arguments['subject']) || empty($arguments['subject']) || !\is_object($arguments['subject'])) {
+            throw new \BadMethodCallException("No subject given for the $eventName event");
+        }
+
+        // Create and return the event object
+        if (class_exists($eventClassName, true)) {
+            return new $eventClassName($eventName, $arguments);
+        }
+
+        /**
+         * The detection code above failed. This is to be expected, it was written back when we only
+         * had the Table events. It does not address most other core events. So, let's use our
+         * fancier detection instead.
+         */
+        $eventClassName = self::getEventClassByEventName($eventName);
+
+        if (!empty($eventClassName) && ($eventClassName !== Event::class)) {
+            return new $eventClassName($eventName, $arguments);
+        }
+
+        return new GenericEvent($eventName, $arguments);
+    }
+}

libraries/src/Extension/ExtensionManagerTrait.php

@@ -10,7 +10,7 @@
 namespace Joomla\CMS\Extension;
 
 use Joomla\CMS\Dispatcher\ModuleDispatcherFactory;
-use Joomla\CMS\Event\AbstractEvent;
+use Joomla\CMS\Event\EventFactory;
 use Joomla\CMS\Helper\HelperFactory;
 use Joomla\CMS\Plugin\CMSPlugin;
 use Joomla\CMS\Plugin\PluginHelper;
@@ -122,7 +122,7 @@ private function loadExtension($type, $extensionName, $extensionPath)
 
         $container->get(DispatcherInterface::class)->dispatch(
             'onBeforeExtensionBoot',
-            AbstractEvent::create(
+            EventFactory::create(
                 'onBeforeExtensionBoot',
                 [
                     'subject'       => $this,
@@ -163,7 +163,7 @@ private function loadExtension($type, $extensionName, $extensionPath)
 
         $container->get(DispatcherInterface::class)->dispatch(
             'onAfterExtensionBoot',
-            AbstractEvent::create(
+            EventFactory::create(
                 'onAfterExtensionBoot',
                 [
                     'subject'       => $this,

libraries/src/MVC/Model/AdminModel.php

@@ -10,6 +10,7 @@
 namespace Joomla\CMS\MVC\Model;
 
 use Joomla\CMS\Component\ComponentHelper;
+use Joomla\CMS\Event\EventFactory;
 use Joomla\CMS\Event\Model;
 use Joomla\CMS\Factory;
 use Joomla\CMS\Form\FormFactoryInterface;
@@ -705,7 +706,7 @@ protected function batchTag($value, $pks, $contexts)
                 $this->table->reset();
                 $this->table->load($pk);
 
-                $setTagsEvent = \Joomla\CMS\Event\AbstractEvent::create(
+                $setTagsEvent = EventFactory::create(
                     'onTableSetNewTags',
                     [
                         'subject'     => $this->table,