Test case for issue rails/rails#8217

test_8217.rb

unless File.exists?('Gemfile')
  File.write('Gemfile', <<-GEMFILE)
    source 'https://rubygems.org'
    gem 'rails', github: 'rails/rails'
    gem 'sqlite3'
  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: 'sqlite3', database: ':memory:')
ActiveRecord::Base.logger = Logger.new(STDOUT)

ActiveRecord::Schema.define do
  create_table "buildings" do |t|
    t.string   "name"
  end

  create_table "departments" do |t|
    t.string   "name"
  end

  create_table "rooms" do |t|
    t.string   "name"
    t.integer  "building_id"
    t.integer  "department_id"
  end
end

class Building < ActiveRecord::Base
  has_many :rooms, dependent: :destroy
  validates :name, presence: true
end

class Department < ActiveRecord::Base
  has_many :rooms, dependent: :nullify
  validates :name, presence: true
end

class Room < ActiveRecord::Base
  belongs_to :building
  belongs_to :department
  validates :name, presence: true
  # There is no building_id validation, as room can be outside buildings (YEAH!)
  default_scope -> { includes(:building).order("rooms.name ASC, buildings.name ASC").references(:building) }
end

class BugTest < MiniTest::Unit::TestCase
  def test_association_stuff
    building   = Building.create!(name: "Main")
    department = Department.create!(name: "IT")
    room = Room.create!(name: "1", building: building, department: department)

    # Start of hack
    # Well, I've not found `refute_raises` assertion
    # refute_raises(ActiveRecord::StatementInvalid) { department.destroy! }
    fail = false
    begin
      department.destroy!
    rescue ActiveRecord::StatementInvalid
      fail = true
    end
    assert_equal false, fail, "Shouldn't raise StatementInvalid error"
    # End of hack

    # Other checks
    assert_equal 1, Building.count, "Shouldn't delete building"
    assert_equal 0, Department.count, "Should delete department"
    assert_equal 1, Room.count, "Shouldn't delete room"

  end
end