add_right_association

# File activerecord/lib/active_record/associations/builder/has_and_belongs_to_many.rb, line 69
        def self.add_right_association(name, options)
          rhs_name = name.to_s.singularize.to_sym
          belongs_to rhs_name, required: false, **options
          self.right_reflection = _reflect_on_association(rhs_name)
        end