Chaining `SorbetOperation::Base` operations

chainability.rb

class BlockOperation < BaseOperation
  def initialize(&blk)
    @blk = blk
  end
  def execute
    @blk.call
  end
end

class BaseOperation < SorbetOperation::Base
  def chain(&blk)
    BlockOperation.new do
      return_value = nil
      my_result_object = self.perform
      my_result_object.on_success do |self_result|
        return_value = (yield self_result).perform
      end
      if return_value
        return_value.unwrap!
      else
        raise my_result_object.unwrap_error!
      end
    end
  end
end

demo.rb

class ProducesList < BaseOperation
  def initialize(howmany)
    @howmany = howmany
  end
  def execute
    if @howmany == 5
        raise SorbetOperation::Failure, "uh oh"
    end
    return ["hello"] * @howmany
  end
end

class ProducesNumber < BaseOperation
  def initialize(howmany)
    @howmany = howmany
  end

  def execute
    return @howmany
  end
end

class Concats < BaseOperation
  def initialize(items, to_add)
    @items = items
    @to_add = to_add
  end

  def execute
    @items.map do |item|
      item + @to_add
    end
  end
end
fails = ProducesNumber.new(5).chain do |n|
  ProducesList.new(n).chain do |items|
    Concats.new(items, n.to_s * 5)
  end
end

succeeds = ProducesNumber.new(10).chain do |n|
  ProducesList.new(n).chain do |items|
    Concats.new(items, n.to_s * 5)
  end
end