This one I would approach like this:
```ruby
  describe '#recipients' do                                                     
    it 'returns emails of users to be notified of news' do                      
      fake_user = mock(:pref => {}, :mail => 'b@b.com', :allowed_to? => true)   
      project.stub(:notified_users).and_return([fake_user])                     
      news.recipients.should == ['b@b.com']                                     
    end                                                                         
  end
```