title: Test fails when adding ":remember_token"
body: <p>I'm following chapter 8 of Michale Hartl's tutorial. When I add:</p>
  
  <pre><code>  it { should respond_to(:remember_token) }
  </code></pre>
  
  <p>to the user_spec.rb file the test fails, with the failure notice pointing directly to this one line in the file. </p>
  
  <p>Prior to adding this line, all tests past. </p>
  
  <p>The only other steps I took after adding this line (and before running the test) was to run a remember token:</p>
  
  <pre><code>$ rails generate migration add_remember_token_to_users
  </code></pre>
  
  <p>I then updated db/migrate/[timestamp]_add_remember_token_to_users.rb as follows:</p>
  
  <pre><code>class AddRememberTokenToUsers &lt; ActiveRecord::Migration
    def change
      add_column :users, :remember_token, :string
      add_index  :users, :remember_token
    end
  end
  </code></pre>
  
  <p>and development and test databases as usual:</p>
  
  <pre><code>$ bundle exec rake db:migrate
  $ bundle exec rake db:test:prepare
  </code></pre>