ransack double self join issue

test-ransack-double-self-join.rb

# test-ransack-double-self-join.rb
# This is a stand-alone test case.
# Run it in your console with: `ruby test-ransack-scope-and-column-same-name.rb`
# If you change the gem dependencies, run it with:
# `rm gemfile* && ruby test-ransack-scope-and-column-same-name.rb`

unless File.exist?('Gemfile')
  File.write('Gemfile', <<-GEMFILE)
    source 'https://rubygems.org'
    # Rails master
    gem 'rails', '~> 5.0.1'
    #gem 'rails', github: 'rails/rails'
    gem 'sqlite3'
    gem 'byebug'
    gem 'ransack', github: 'activerecord-hackery/ransack'
    #gem 'ransack', '= 1.8.2' # github: 'activerecord-hackery/ransack'
    #gem 'polyamorous', github: 'activerecord-hackery/polyamorous'
  GEMFILE

  system 'bundle install'
end

require 'bundler'
Bundler.setup(:default)

require 'active_record'
require 'minitest/autorun'
require 'logger'
require 'ransack'

# This connection will do for database-independent bug reports.
ActiveRecord::Base.establish_connection(adapter: 'sqlite3', database: ':memory:')
ActiveRecord::Base.logger = Logger.new(STDOUT)

# Display versions.
message = "Running test case with Ruby #{RUBY_VERSION}, Active Record #{
  ::ActiveRecord::VERSION::STRING}, Arel #{Arel::VERSION} and #{
  ::ActiveRecord::Base.connection.adapter_name}"
line = '=' * message.length
puts line, message, line

ActiveRecord::Schema.define do
  create_table :items, force: true do |t|
    t.integer "parent_item_id"
    t.integer "item_info_id"
  end
  create_table :item_infos, force: true do |t|
    t.string "name"
  end
end

class Item < ActiveRecord::Base
  belongs_to :parent, foreign_key: :parent_item_id, class_name: "Item"
  has_many :children, foreign_key: :parent_item_id, class_name: "Item"
  belongs_to :item_info
end

class ItemInfo < ActiveRecord::Base
  has_many :items
end

class BugTest < Minitest::Test
  def test_parent_item_info_name
    #require 'byebug' ; byebug
    sql = ItemInfo.ransack({ items_parent_item_info_name_cont: "Foo" }).result.to_sql
    puts sql
    assert_equal(
      "SELECT \"item_infos\".* FROM \"item_infos\" LEFT OUTER JOIN \"items\" ON \"items\".\"item_info_id\" = \"item_infos\".\"id\" LEFT OUTER JOIN \"items\" \"parents_items\" ON \"parents_items\".\"id\" = \"items\".\"parent_item_id\" LEFT OUTER JOIN \"item_infos\" \"item_infos_items\" ON \"item_infos_items\".\"id\" = \"parents_items\".\"item_info_id\" WHERE (\"item_infos_items\".\"name\" LIKE '%Foo%')", sql
      )
  end
end