[4.2] Inject the application into the service provider plugins

administrator/components/com_scheduler/src/Traits/TaskPluginTrait.php

@@ -215,7 +215,7 @@ protected function getRoutineId(Form $form, $data): string
 		// If we're unable to find a routineId, it might be in the form input.
 		if (empty($routineId))
 		{
-			$app       = $this->app ?? Factory::getApplication();
+			$app       = $this->getApplication() ?? ($this->app ?? Factory::getApplication());
 			$form      = $app->getInput()->get('jform', []);
 			$routineId = ArrayHelper::getValue($form, 'type', '', 'STRING');
 		}
@@ -248,7 +248,7 @@ protected function logTask(string $message, string $priority = 'info'): void
 
 		if (!$langLoaded)
 		{
-			$app = $this->app ?? Factory::getApplication();
+			$app = $this->getApplication() ?? ($this->app ?? Factory::getApplication());
 			$app->getLanguage()->load('com_scheduler', JPATH_ADMINISTRATOR);
 			$langLoaded = true;
 		}

libraries/src/Plugin/CMSPlugin.php

@@ -10,6 +10,7 @@
 
 \defined('JPATH_PLATFORM') or die;
 
+use Joomla\CMS\Application\CMSApplicationInterface;
 use Joomla\CMS\Extension\PluginInterface;
 use Joomla\CMS\Factory;
 use Joomla\Event\AbstractEvent;
@@ -75,6 +76,15 @@ abstract class CMSPlugin implements DispatcherAwareInterface, PluginInterface
 	 */
 	protected $allowLegacyListeners = true;
 
+	/**
+	 * The application object
+	 *
+	 * @var    CMSApplicationInterface
+	 *
+	 * @since  __DEPLOY_VERSION__
+	 */
+	private $application;
+
 	/**
 	 * Constructor
 	 *
@@ -120,6 +130,7 @@ public function __construct(&$subject, $config = array())
 
 		if (property_exists($this, 'app'))
 		{
+			@trigger_error('The application should be injected through setApplication() and requested through getApplication().', E_USER_DEPRECATED);
 			$reflection = new \ReflectionClass($this);
 			$appProperty = $reflection->getProperty('app');
 
@@ -131,6 +142,7 @@ public function __construct(&$subject, $config = array())
 
 		if (property_exists($this, 'db'))
 		{
+			@trigger_error('The database should be injected through the DatabaseAwareInterface and trait.', E_USER_DEPRECATED);
 			$reflection = new \ReflectionClass($this);
 			$dbProperty = $reflection->getProperty('db');
 
@@ -162,7 +174,7 @@ public function loadLanguage($extension = '', $basePath = JPATH_ADMINISTRATOR)
 		}
 
 		$extension = strtolower($extension);
-		$lang      = Factory::getLanguage();
+		$lang      = $this->getApplication() ? $this->getApplication()->getLanguage() : Factory::getLanguage();
 
 		// If language already loaded, don't load it again.
 		if ($lang->getPaths($extension))
@@ -174,6 +186,31 @@ public function loadLanguage($extension = '', $basePath = JPATH_ADMINISTRATOR)
 			|| $lang->load($extension, JPATH_PLUGINS . '/' . $this->_type . '/' . $this->_name);
 	}
 
+	/**
+	 * Translates the given key with the local applications language. If arguments are available, then
+	 * injects them into the translated string.
+	 *
+	 * @param   string   $key        The key to translate
+	 * @param   mixed[]  $arguments  The arguments
+	 *
+	 * @return  string  The translated string
+	 *
+	 * @since   __DEPLOY_VERSION__
+	 *
+	 * @see     sprintf
+	 */
+	protected function translate(string $key, ...$arguments): string
+	{
+		$language = $this->getApplication()->getLanguage();
+
+		if ($arguments)
+		{
+			return sprintf($language->_($key), ...$arguments);
+		}
+
+		return $language->_($key);
+	}
+
 	/**
 	 * Registers legacy Listeners to the Dispatcher, emulating how plugins worked under Joomla! 3.x and below.
 	 *
@@ -359,4 +396,30 @@ private function parameterImplementsEventInterface(\ReflectionParameter $paramet
 
 		return false;
 	}
+
+	/**
+	 * Returns the internal application or null when not set.
+	 *
+	 * @return  CMSApplicationInterface|null
+	 *
+	 * @since   __DEPLOY_VERSION__
+	 */
+	protected function getApplication(): ?CMSApplicationInterface
+	{
+		return $this->application;
+	}
+
+	/**
+	 * Sets the application to use.
+	 *
+	 * @param   CMSApplicationInterface  $application  The application
+	 *
+	 * @return  void
+	 *
+	 * @since   __DEPLOY_VERSION__
+	 */
+	public function setApplication(CMSApplicationInterface $application): void
+	{
+		$this->application = $application;
+	}
 }

plugins/actionlog/joomla/services/provider.php

@@ -10,6 +10,7 @@
 defined('_JEXEC') or die;
 
 use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
 use Joomla\CMS\Plugin\PluginHelper;
 use Joomla\Database\DatabaseInterface;
 use Joomla\DI\Container;
@@ -38,6 +39,7 @@ function (Container $container)
 					$container->get(DispatcherInterface::class),
 					(array) PluginHelper::getPlugin('actionlog', 'joomla')
 				);
+				$plugin->setApplication(Factory::getApplication());
 				$plugin->setDatabase($container->get(DatabaseInterface::class));
 
 				return $plugin;