Fixes #711.

framework/yii/base/Application.php

@@ -180,6 +180,16 @@ abstract class Application extends Module
 	}
 
 	/**
+	 * Returns an ID that uniquely identifies this module among all modules within the current application.
+	 * Since this is an application instance, it will always return an empty string.
+	 * @return string the unique ID of the module.
+	 */
+	public function getUniqueId()
+	{
+		return '';
+	}
+
+	/**
 	 * Runs the application.
 	 * This is the main entrance of an application.
 	 * @return integer the exit status (0 means normal, non-zero values mean abnormal)

framework/yii/base/Module.php

@@ -192,13 +192,7 @@ abstract class Module extends Component
 	 */
 	public function getUniqueId()
 	{
-		if ($this instanceof Application) {
-			return '';
-		} elseif ($this->module) {
-			return ltrim($this->module->getUniqueId() . '/' . $this->id, '/');
-		} else {
-			return $this->id;
-		}
+		return $this->module ? ltrim($this->module->getUniqueId() . '/' . $this->id, '/') : $this->id;
 	}
 
 	/**