$ ./script/console
Loading development environment.
>> helper.human_size(5000000000)
=> "4.7 GB"
>> helper.link_to 'test', :action => 'test'
NoMethodError: You have a nil object when you didn't expect it!
The error occurred while evaluating nil.url_for
        from ./script/../config/../config/../vendor/rails/actionpack/lib/action_view/helpers/url_helper.rb:27:in `send'
        from ./script/../config/../config/../vendor/rails/actionpack/lib/action_view/helpers/url_helper.rb:27:in `url_for'
        from ./script/../config/../config/../vendor/rails/actionpack/lib/action_view/helpers/url_helper.rb:75:in `link_to'
        from (irb):2
>>