# File lib/polyamorous/activerecord_4.2_ruby_1.9/join_dependency.rb, line 49
    def join_constraints_with_polymorphism(outer_joins)
      joins = join_root.children.flat_map { |child|
        make_polyamorous_inner_joins join_root, child
      }
      joins.concat outer_joins.flat_map { |oj|
        if join_root.match? oj.join_root
          walk(join_root, oj.join_root)
        else
          oj.join_root.children.flat_map { |child|
            make_outer_joins(oj.join_root, child)
          }
        end
      }
    end