Instead of defining an ActiveRecord class that acts like an ActiveResource class, I'd rather just make an ActiveResource class.

There's already a file in spec/support/model_builder.rb which is where define_model is defined. Can you:

* make a corresponding active_resource_builder.rb file in spec/support
* define a define_active_resource_class method in there - I forget how ActiveResource works but if it works like ActiveModel does you can probably copy from define_active_model_class, otherwise I'm not really sure here.
* use define_active_resource_class here instead of define_model?