Rails 4 issue 18862 test

rails-420-issue-18862-regression.rb

# Activate the gem you are reporting the issue against.
gem 'activerecord', '4.2.0'
require 'active_record'
require 'minitest/autorun'
require 'logger'

# Ensure backward compatibility with Minitest 4
Minitest::Test = MiniTest::Unit::TestCase unless defined?(Minitest::Test)

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

ActiveRecord::Schema.define do
  create_table :bookings do |t|
    t.integer :client_id
    t.string :status
    t.datetime :start_time
  end
end

class Booking < ActiveRecord::Base
  scope :cancelled, -> { where(:status => :cancelled) }
  scope :by_new_client, -> { a = arel_table.alias; where(:start_time => Booking.select('min(bookings_2.start_time)').from(a).where(:client_id => a[:client_id])) }
end

class BugTest < Minitest::Test
  def test_scopes_order_doesnt_matter
    sql1 = Booking.cancelled.by_new_client.to_sql
    sql2 = Booking.by_new_client.cancelled.to_sql

    assert sql1 == sql2, 'Generated SQL must be the same'
  end
end