Module: ActsAsNestedBy::ClassMethods

Defined in:
lib/acts_as_nested_by.rb

Instance Method Summary collapse

Instance Method Details

#acts_as_nested_by(*association_names) ⇒ Object

Generates instance methods for setting and getting a ‘nested_by_other’ flag for each ‘:other’ in association_names

  • Example:

    Bar < ActiveRecord::Base
  belongs_to :other
  acts_as_nested_by :other
end

    generates methods

    Bar#nested_by_other=
Bar#nested_by_other
Bar#nested_by_other?

  • Exceptions raised

    • ArgumentError if one of the associations does not exist

    • ArgumentError if one of the associations is not created by the :belongs_to macro



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# File 'lib/acts_as_nested_by.rb', line 21

def acts_as_nested_by(*association_names)
  association_names.each do |association_name|
    if reflection = reflect_on_association(association_name)
      if :belongs_to == reflection.macro
        class_eval %{
          def nested_by_#{association_name}=(nested_by_#{association_name})
            @nested_by_#{association_name} = nested_by_#{association_name}
          end

          def nested_by_#{association_name}
            @nested_by_#{association_name} = !@nested_by_#{association_name} ? false : true
          end

          def nested_by_#{association_name}?
            nested_by_#{association_name}
          end
        }
      else
        raise ArgumentError, "Association `#{association_name}' must be :belongs_to but it's `#{reflection.macro}'."
      end
    else
      raise ArgumentError, "No association found for name `#{association_name}'. Has it been defined yet?"
    end
  end
end