Stubbing Chained Queries in Rails 3 and Rspec

Question

I'm trying to test a scope I have that is based upon a chain of other scopes. ("public_stream" below).

scope :public, where("entries.privacy = 'public'")
scope :completed, where("entries.observation <> '' AND entries.application <> ''")
scope :without_user, lambda { |user| where("entries.user_id <> ?", user.id) }
scope :public_stream, lambda { |user| public.completed.without_user(user).limit(15) }

Using a test like this:

    it "should use the public, without_user, completed, and limit scopes" do
      @chain = mock(ActiveRecord::Relation)
      Entry.should_receive(:public).and_return(@chain)
      @chain.should_receive(:without_user).with(@user).and_return(@chain)
      @chain.should_receive(:completed).and_return(@chain)
      @chain.should_receive(:limit).with(15).and_return(Factory(:entry))

      Entry.public_stream(@user)
    end

However, I continue to receive this error:

Failure/Error: Entry.public_stream(@user)
undefined method `includes_values' for #<Entry:0xd7b7c0>

It seems includes_values is an instance variable of the ActiveRecord::Relation object, but when I try to stub it, I still receive the same error. I was wondering if anyone had experience with stubing Rails 3's new chained queries? I can find a bunch of discussion over 2.x's find hash, but nothing on how to test what's current.

Answer 1

I use rspec's stub_chain for this. You might be able to use something like:

some_model.rb

scope :uninteresting, :conditions => ["category = 'bad'"],
                      :order => "created_at DESC"

Controller

@some_models = SomeModel.uninteresting.where(:something_else => true)

spec

SomeModel.stub_chain(:uninteresting, :where) {mock_some_model}