title: NoMethodError: undefined method `belong_to' for #<RSpec::Core::ExampleGroup::Nested_4:0xa05d2a0>
body: <p>So this is kind of baffling me as I can't quite figure out why it's happening. This only happens on my laptop (Ubuntu 11.04), and not elsewhere.  I just seem to have something weird with the setup on this one computer.  </p>
  
  <p>I keep getting the following error when I run my specs:</p>
  
  <pre><code>be rake spec
  </code></pre>
  
  <p>Gives me:</p>
  
  <pre><code>NoMethodError: undefined method `belong_to' for #&lt;RSpec::Core::ExampleGroup::Nested_4:0xb4eb2e4&gt;
  /home/tom/.rvm/gems/ruby-1.9.2-p290@litdistco/gems/rspec-expectations-2.6.0/lib/rspec/matchers/method_missing.rb:9:in `method_missing'
  /home/tom/work/ruby/litdistco-sales/spec/models/sales_item_spec.rb:5:in `block (2 levels) in &lt;top (required)&gt;'
  /home/tom/.rvm/gems/ruby-1.9.2-p290@litdistco/gems/rspec-core-2.6.4/lib/rspec/core/example.rb:48:in `instance_eval'
  /home/tom/.rvm/gems/ruby-1.9.2-p290@litdistco/gems/rspec-core-2.6.4/lib/rspec/core/example.rb:48:in `block in run'
  /home/tom/.rvm/gems/ruby-1.9.2-p290@litdistco/gems/rspec-core-2.6.4/lib/rspec/core/example.rb:107:in `with_around_hooks'
  /home/tom/.rvm/gems/ruby-1.9.2-p290@litdistco/gems/rspec-core-2.6.4/lib/rspec/core/example.rb:45:in `run'
  /home/tom/.rvm/gems/ruby-1.9.2-p290@litdistco/gems/rspec-core-2.6.4/lib/rspec/core/example_group.rb:294:in `block in run_examples'
  /home/tom/.rvm/gems/ruby-1.9.2-p290@litdistco/gems/rspec-core-2.6.4/lib/rspec/core/example_group.rb:290:in `map'
  /home/tom/.rvm/gems/ruby-1.9.2-p290@litdistco/gems/rspec-core-2.6.4/lib/rspec/core/example_group.rb:290:in `run_examples'
  /home/tom/.rvm/gems/ruby-1.9.2-p290@litdistco/gems/rspec-core-2.6.4/lib/rspec/core/example_group.rb:262:in `run'
  /home/tom/.rvm/gems/ruby-1.9.2-p290@litdistco/gems/rspec-core-2.6.4/lib/rspec/core/command_line.rb:24:in `block (2 levels) in run'
  /home/tom/.rvm/gems/ruby-1.9.2-p290@litdistco/gems/rspec-core-2.6.4/lib/rspec/core/command_line.rb:24:in `map'
  /home/tom/.rvm/gems/ruby-1.9.2-p290@litdistco/gems/rspec-core-2.6.4/lib/rspec/core/command_line.rb:24:in `block in run'
  /home/tom/.rvm/gems/ruby-1.9.2-p290@litdistco/gems/rspec-core-2.6.4/lib/rspec/core/reporter.rb:12:in `report'
  /home/tom/.rvm/gems/ruby-1.9.2-p290@litdistco/gems/rspec-core-2.6.4/lib/rspec/core/command_line.rb:21:in `run'
  /home/tom/.rvm/gems/ruby-1.9.2-p290@litdistco/gems/rspec-core-2.6.4/lib/rspec/core/runner.rb:80:in `run_in_process'
  /home/tom/.rvm/gems/ruby-1.9.2-p290@litdistco/gems/rspec-core-2.6.4/lib/rspec/core/runner.rb:69:in `run'
  /home/tom/.rvm/gems/ruby-1.9.2-p290@litdistco/gems/rspec-core-2.6.4/lib/rspec/core/runner.rb:11:in `block in autorun'
  </code></pre>
  
  <p>Here are the relevant lines from my spec file that generates the complaint:</p>
  
  <pre><code>describe SalesItem do
    it { should belong_to(:publisher) }
    it { should belong_to(:invoice) }
  </code></pre>
  
  <p>I'm running Rails 3.1.0.  Here is ruby -v:</p>
  
  <pre><code>ruby 1.9.2p290 (2011-07-09 revision 32553) [i686-linux]
  </code></pre>
  
  <p>Any tips /thoughts/ideas recommendations greatly appreciated.</p>