public function isDryRun()
    {
        if (null === $this->isDryRun) {
            if ($this->isStdIn()) {
                // Can't write to STDIN
                $this->isDryRun = true;
            } else {
                $this->isDryRun = $this->options['dry-run'];
            }
        }

        return $this->isDryRun;
    }