protected function configureVariables(array $files)
    {
        foreach ($files as $file => $values) {
            $file = "{$this->path}/{$file}";
            if (! file_exists($file)) {
                throw new \Exception("TRIPALTEST: Unable to configure variables. $file does not exist!");
            }

            $content = file_get_contents($file);
            foreach ($values as $search => $replace) {
                $content = str_replace($search, $replace, $content);
            }

            file_put_contents($file, $content);
        }
    }