require 'abstract_unit' require 'active_support/deprecation' require 'active_support/basic_object' class BasicObjectTest < ActiveSupport::TestCase test 'BasicObject warns about deprecation when inherited from' do warn = 'ActiveSupport::BasicObject is deprecated! Use ActiveSupport::ProxyObject instead.' ActiveSupport::Deprecation.expects(:warn).with(warn).once Class.new(ActiveSupport::BasicObject) end end