yield_self_usage.rb

# app/controllers/concerns/campaign_transaction_swap_prize.rb:294
def prepare_swappable_prizes
  @swappable_prizes =
    (
      if campaign.prize_type(@transaction.prize_amount, @transaction.office_id) == 'Small
        Prize.equal_value_for_swapping(@transaction, campaign).yield_self do |prizes|
          prizes.presence || Prize.lower_value_for_swapping(@transaction, campaign)  
        end
      else
        Prize.any_value_for_swapping(@transaction, campaign)
      end
    ).format_for_swapping
end

def prepare_swappable_prizes
  if campaign.prize_type(@transaction.prize_amount, @transaction.office_id) == 'Small'
    @swappable_prizes = Prize.equal_value_for_swapping(@transaction, campaign).format_for_swapping
    unless @swappable_prizes.any?
      @swappable_prizes = Prize.lower_value_for_swapping(@transaction, campaign).format_for_swapping
    end
  else
    @swappable_prizes = Prize.any_value_for_swapping(@transaction, campaign).format_for_swapping
  end
end