gistfile1.rb

  def update
    wylayps= JSON.parse(params[:wylayps])
    wylayps.each do |w|
      Wylayp.update(w.delete :id, w)
    end
    respond_to do |format|
      format.json { render :json => [] }
    end
  end

gistfile2.rb

require File.join('spec', 'spec_helper')

describe WylaypController do
  describe "#update" do
    it_should_require_a_logged_in_user do 
      wylayps= mock("wylayps")
      wylayps.stub(:each)
      JSON.stub(:parse).and_return(wylayps)
      put :update 
    end

    describe "when logged in" do
      before(:each) do
        fake_login()
        wylayp= mock("wylayp").as_null_object
        JSON.stub(:parse).and_return([wylayp,wylayp])
      end

      it "should update as many Wylayps as received" do   
        Wylayp.should_receive(:update).twice
        put :update
      end

      it "should respond with JSON [] if successful" do
        Wylayp.stub(:update)
        put :update
        response.body.should eql "[]"
      end
    end
  end
end