title: rspec assert_equal no method error
body: <pre><code>undefined method 'assert_equal' for #&lt;RSpec::Core::ExampleGroup::Nested_1:0x8d6f75c&gt;
  </code></pre>
  
  <p>gem list</p>
  
  <pre><code>bundler (1.3.5)
  diff-lcs (1.2.3)
  rspec (2.13.0)
  rspec-core (2.13.1)
  rspec-expectations (2.13.0)
  rspec-mocks (2.13.1)
  test-unit (2.5.4)
  </code></pre>
  
  <p>spec_helper.rb</p>
  
  <pre><code>require './lib/checkout.rb'
  require './lib/product.rb'
  require 'rspec'
  
  RSpec.configure do |config|
    config.treat_symbols_as_metadata_keys_with_true_values = true
    config.run_all_when_everything_filtered = true
    config.filter_run :focus
  end
  </code></pre>