protected function setupExecution() {
    $this->setOptionsForLastCommand();
    $this->setGlobalOptions();

    $globalOptions = $this->arguments;

    foreach ($this->commands as $commandNumber => $command) {
      if ($this->alias) {
        $command = "@{$this->alias} {$command}";
      }

      $options = isset($this->options[$commandNumber]) ? $this->options[$commandNumber] : '';

      // Add in global options, as well as those set via option method.
      $command = $command . $options . $globalOptions;

      $this->exec($command)
        ->dir($this->dir);
    }
  }