Rspec2: response.should render_template("new") after invalid params fails

Question

I am testing a controller in RSpec2 and for both my create and update actions, when passed invalid params, the controller should render either the "new" or "edit" templates respectively. It is doing that, but my test never passes.

describe "with invalid params" do
    before(:each) do
      User.stub(:new) { mock_user(:valid? => false, :save => false) }
    end

    it "re-renders the 'new' template" do
      post :create, :company_id => mock_company.id
      response.should render_template("new")
    end
  end

Results in this:

re-renders the 'new' template
expecting <"new"> but rendering with <"">

Here is the controller action:

respond_to do |format|
  if @user.save
    format.html {
      flash[:notice] = "#{@user.full_name} was added to #{@company.name}."
      redirect_to company_users_url(@company)
    }
  else
    logger.debug @user.errors
    format.html{
      render :new
    }
  end
end

This problem also seems to be isolated to this controller. I have almost identical code running another controller and it is fine. I am not sure where the problem could be.

Update: Here are the two mock methods

def mock_user(stubs={})
  @mock_user ||= mock_model(User, stubs).as_null_object
end

def mock_company(stubs={})
  (@mock_company ||= mock_model(Company).as_null_object).tap do |company|
    company.stub(stubs) unless stubs.empty?
  end
end

Answer 1

Turned out it was a problem with stubbing and CanCan. CanCan was loading the resources and uses some different methods than what I thought.