Fix tests

lib/classes/base.php

@@ -144,19 +144,6 @@ abstract class base implements cache_cacheableInterface
         return $this->connection;
     }
 
-    /**
-     * Replaces the connection
-     *
-     * @param  \connection_pdo $connection
-     * @return \base
-     */
-    public function set_connection(\connection_pdo $connection)
-    {
-        $this->connection = $connection;
-
-        return $this;
-    }
-
     public function get_cache()
     {
         return $this->app['cache'];