对 find 的期望不起作用，但对 find_by_id 的期望是

Question

我有这个控制器代码：

# GET /cardsets/1
def show
  @cardset = current_user.cardsets.find_by_id(params[:id])
end

还有这个 RSpec 测试代码（用 Mocha 模拟）：

# GET Show
context "on get to show" do
  it "should assign cardset" do
    @cardset = Factory(:cardset)
    @profile = @cardset.profile

    @profile.cardsets.expects(:find).once.returns(@cardset)
    get :show, :id => @cardset.id
    assigns[:cardset].should_not be_nil
  end
end

此测试失败：

2)
Mocha::ExpectationError in 'CardsetsController for a logged in user on get to show should assign cardset'
not all expectations were satisfied
unsatisfied expectations:
- expected exactly once, not yet invoked: [#<Cardset:0x1032bb660>].find(any_parameters)
satisfied expectations:
- allowed any number of times, not yet invoked: ApplicationController.require_user(any_parameters)
- allowed any number of times, already invoked twice:     #<CardsetsController:0x10336c578>.current_user(any_parameters)

如果我将期望更改为：

@profile.cardsets.expects(:find_by_id).once.returns(@cardset)

那么测试就通过了，为什么这个用find_by_id会通过而找不到呢？

Answer 1

我认为这是因为find 和find_by_id 实际上是不同的消息。您的控制器使用find_by_id，但您将消息期望设置为查找find。