Actualización

vendor/doctrine/migrations/lib/Doctrine/DBAL/Migrations/IrreversibleMigrationException.php

@@ -0,0 +1,16 @@
+<?php
+
+namespace Doctrine\DBAL\Migrations;
+
+/**
+ * Exception to be thrown in the down() methods of migrations that signifies it
+ * is an irreversible migration and stops execution.
+ *
+ * @license     http://www.opensource.org/licenses/lgpl-license.php LGPL
+ * @link        www.doctrine-project.org
+ * @since       2.0
+ * @author      Jonathan H. Wage <jonwage@gmail.com>
+ */
+class IrreversibleMigrationException extends \Exception
+{
+}