code: func (c *runner) RunWithOptions(opts CommandOpts, name string, arg ...string) error {
  	cmd := exec.Command(name, arg...)
  	if opts.Stdout != nil {
  		cmd.Stdout = opts.Stdout
  	}
  	if opts.Stderr != nil {
  		cmd.Stderr = opts.Stderr
  	}
  	if opts.Dir != "" {
  		cmd.Dir = opts.Dir
  	}
  	if len(opts.EnvAppend) > 0 {
  		cmd.Env = os.Environ()
  		cmd.Env = append(cmd.Env, opts.EnvAppend...)
  	}
  	return cmd.Run()
  }
docs: // RunWithOptions runs a command with the provided options