Rspec example for nested resource index action

def index

  if params[:user_id]

    @user = User.find(params[:user_id])

    @messages = @user.messages

  end

end

Here's the spec:

describe MessagesController, " handling GET /messages for a user" do

before do
   @user = mock_model(User) 
   @messages = mock("messages")
   @user.stub!(:messages).and_return(@messages)
   User.stub!(:find).and_return(@user)
end

def do_get 
   get :index, :user_id => 1
end

it "should render index template" do
   do_get
   response.should render_template('index')
end

it "should find user with params[:user_id]" do 
   User.should_receive(:find).with(1).and_return(@user)
   do_get
end

it "should get user's messages" do
   @user.should_receive(:messages).and_return(@messages)
   do_get
end

it "should assign the found messages for the view" do
   do_get
   assigns[:messages].should be(@messages)
end
end