gistfile1.rb

describe "POST create" do
  describe "with valid params" do
    it "assigns a newly created attending as @attending" do
      Attending.stub(:new).with({'event_id' => 1}) { mock_attending(:save => true) }
      post :create, :event_id => 1
      assigns(:attending).should be(mock_attending)
    end
  end
end


Produces:
Failure/Error: post :create, :event_id => 1
  <Attending(id: integer, user_id: integer, event_id: integer, created_at: datetime, updated_at: datetime) (class)> received :new with unexpected arguments
    expected: ({"event_id"=>1})
    got: ({:event_id=>1})