ruby-on-rails – any_instance should_receive无法正常工作

我有这样的代码：

@dns = "#{params[:domain].split('/').reverse.join('.')}.#{params[:zone]}"
w = Whois::Client.new
@r = w.query(@dns)

有路线：

@H_326_2@match "domains/:zone/*domain" => "domains#show"

我正在使用Whois Gem

我想测试一下,所以我有一个测试：

it "should query 'google.com.ua' from /ua/com/google" do
    get :show,:zone => 'ua',:domain => 'com/google'
    dns = "google.com.ua"
    Whois::Client.any_instance.should_receive(:query).with(dns)
end

结果我得到：

Exactly one instance should have received the following message(s) but didn't: query

哪里可以问题？我100％肯定.query被调用