Ensure that a connection exists in rollback.

Calling rollbackTransaction on a disconnected driver should not fatally error.

Author: markstory

src/Database/Driver/PDODriverTrait.php

@@ -139,12 +139,13 @@ public function commitTransaction()
     }
 
     /**
-     * Rollsback a transaction
+     * Rollback a transaction
      *
      * @return bool true on success, false otherwise
      */
     public function rollbackTransaction()
     {
+        $this->connect();
         if (!$this->_connection->inTransaction()) {
             return false;
         }

tests/TestCase/Database/Driver/MysqlTest.php

@@ -141,4 +141,23 @@ public function testIsConnected()
         $connection->connect();
         $this->assertTrue($connection->isConnected(), 'Should be connected.');
     }
+
+    public function testRollbackTransactionAutoConnect()
+    {
+        $connection = ConnectionManager::get('test');
+        $connection->disconnect();
+
+        $driver = $connection->driver();
+        $this->assertFalse($driver->rollbackTransaction());
+        $this->assertTrue($driver->isConnected());
+    }
+
+    public function testCommitTransactionAutoConnect()
+    {
+        $connection = ConnectionManager::get('test');
+        $driver = $connection->driver();
+
+        $this->assertFalse($driver->commitTransaction());
+        $this->assertTrue($driver->isConnected());
+    }
 }