Testing different ways to bring back active records by the source ids

sort_test.rb

#!/usr/bin/env ruby

require 'ostruct'
require 'byebug'
module Enumerable
  def index_by
    if block_given?
      Hash[map { |elem| [yield(elem), elem] }]
    else
      to_enum(:index_by) { size if respond_to?(:size) }
    end
  end
end

class St
  attr_accessor :id
  def initialize(id)
    self.id = id
  end
end

class Model
  def self.where(opts)
    opts[:id].map(&:to_i).sort.map { |id| St.new(id) }
  end
end

ids = ["1","4","5","3","22", "11", "8"]

puts ids.map(&:to_i).inspect
# ==> [1, 4, 5, 3, 22, 11, 8]

recs = Model.where(:id => ids).index_by(&:id)
ret = ids.map { |id| recs[id.to_i] }

puts ret.map(&:id).inspect
# ==> [1, 4, 5, 3, 22, 11, 8]

#ret = Model.where(:id => ids).sort_by.with_index { |e, i| puts "#{i}: #{e.id} => #{ids[i]}" ; ids[i] }
#
#puts ret.map(&:id).inspect
# # ==> [1, 11, 8, 5, 3, 4, 22]

ret = Model.where(:id => ids).sort_by.with_index { |e, i| ids.index(e.id.to_s) }
puts ret.map(&:id).inspect
# ==> [1, 4, 5, 3, 22, 11, 8]

id_i = ids.each_with_object({}).with_index { |(id, h), i| h[id.to_i] = i }
ret = Model.where(:id => ids).sort_by { |e| id_i[e.id] }
puts ret.map(&:id).inspect
# ==> [1, 4, 5, 3, 22, 11, 8]