title: RSpec "Undefined method" order dependency error in Rails 4 in a spec that works in Rails 3.2
body: <p>I have been using a testing workflow in Rails 3.2 for a few months that I picked up from a screencast by Rem Zolotykh.  It is simple and useful for verifying the basic components of the Rails stack.  However, I am using it in Rails 4.0.0 for the first time and I am getting an order dependency error where I have not had one before.  This is the UsersController spec:</p>
  
  <p>require 'spec_helper'</p>
  
  <pre><code>describe UsersController do 
    describe 'POST create' do
      let!(:user) { stub_model(User) }
      it 'sends new message to User class' do # this is the one that fails intermittently
        params = {                            # call this spec 1
          'first_name' =&gt; 'Test',
          'last_name' =&gt; 'Tester',
          'email_address' =&gt; 'test@test.com',
          'password' =&gt; 'secret',
          'password_confirmation' =&gt; 'secret'
        }
        User.stub(:new).and_return(user)
        User.should_receive(:new).with(params)
        post :create, user: params
      end
      it 'sends save message to user model' do # this one always passes
        User.stub(:new).and_return(user)       # call this spec 2
        user.should_receive(:save)
        post :create
      end
    end
  end
  </code></pre>
  
  <p>This is the UsersController:</p>
  
  <pre><code>class UsersController &lt; ApplicationController
    def new
      @user = User.new
    end
  
    def create
      user = User.new(params[:user])
      user.save
      render nothing: true
    end
  end
  </code></pre>
  
  <p>Should be very simple.
  However, when the random test order fires Spec 2 first, then spec 1 passes.  If spec 1 is fired first, it fails but spec 2 still passes.
  The failure error for spec 1:</p>
  
  <pre><code>1) UsersController POST create sends new message to User class
   Failure/Error: post :create, user: params
   NoMethodError:
     undefined method `save' for #&lt;User:0x007f9d1b6baf98&gt;
   # ./app/controllers/users_controller.rb:8:in `create'
   # ./spec/controllers/users_controller_spec.rb:32:in `block (3 levels) in &lt;top (required)&gt;'
  </code></pre>
  
  <p>I am using rspec-core 2.13.1 and rspec-rails 2.13.2.
  I've searched high and low and I have found nothing.
  Any ideas?</p>