rails--rails/activesupport/CHANGELOG.md

• Introduce Module#delegate_missing_to.

  When building a decorator, a common pattern emerges:

  class Partition
    def initialize(first_event)
      @events = [ first_event ]
    end
  
    def people
      if @events.first.detail.people.any?
        @events.collect { |e| Array(e.detail.people) }.flatten.uniq
      else
        @events.collect(&:creator).uniq
      end
    end
  
    private
      def respond_to_missing?(name, include_private = false)
        @events.respond_to?(name, include_private)
      end
  
      def method_missing(method, *args, &block)
        @events.send(method, *args, &block)
      end
  end
  

  With Module#delegate_missing_to, the above is condensed to:

  class Partition
    delegate_missing_to :@events
  
    def initialize(first_event)
      @events = [ first_event ]
    end
  
    def people
      if @events.first.detail.people.any?
        @events.collect { |e| Array(e.detail.people) }.flatten.uniq
      else
        @events.collect(&:creator).uniq
      end
    end
  end
  

  Genadi Samokovarov, DHH

• Rescuable: If a handler doesn't match the exception, check for handlers matching the exception's cause.

  Jeremy Daer

Please check 5-0-stable for previous changes.