rails-14657.rb

unless File.exist?('Gemfile')
  File.write('Gemfile', <<-GEMFILE)
    source 'https://rubygems.org'
    gem 'rails', '~> 4.1'
    gem 'pg'
  GEMFILE

  system 'bundle'
end

require 'bundler'
Bundler.setup(:default)

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

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

ActiveRecord::Schema.define do
  create_table :movies do |t|
  end

  create_table :languages do |t|    
  end

  create_table :cities do |t|    
  end

  create_table :theatres do |t|
    t.references :city
  end

  create_table :shows do |t|        
    t.references :language  
    t.references :movie
  end

  create_table :schedules do |t|
    t.references :show
    t.datetime :schedule_time
    t.references :theatre
  end  
end

class Movie < ActiveRecord::Base
  has_many :schedules, through: :shows
  has_many :shows
end

class Schedule < ActiveRecord::Base  
  belongs_to :show  
  scope :latest, -> { where(schedule_time: 2.minutes.ago)}
  belongs_to :theatre
end

class Show < ActiveRecord::Base
  has_many :schedules
  
  belongs_to :language
  belongs_to :movie
end

class Theatre < ActiveRecord::Base
  has_many :shows
  belongs_to :city
  has_many :schedules, through: :shows
end

class City < ActiveRecord::Base
  has_many :theatres
end

class Language < ActiveRecord::Base
  has_many :shows
end

class BugTest < Minitest::Test
  def test_nested_includes
    movie = Movie.create!

    # Doesn't work - needs `references`
    # schedules = Movie.first.schedules.latest
    #               .includes(:show).includes(theatre: [:city])
    #               .where('cities.id = ?', 42)
    #               .to_a
    
    # Works, But it makes absolutely no difference what you actually reference.
    schedules = Movie.first.schedules.latest
                  .includes(:show).includes(theatre: [:city])
                  .where('cities.id = ?', 42)
                  .references(:whatever_trolololollo).to_a

    # Stops working, as soon as nested associations are eagerly loaded.
    schedules = Movie.first.schedules.latest
                  .includes(show: [:language]).includes(theatre: [:city])
                  .where('cities.id = ?', 42)
                  .references(:useless_symbol).to_a

    # HINT:  Perhaps you meant to reference the table alias "shows_schedules".
  end
end