Rails tests:

begin
  require "bundler/inline"
rescue LoadError => e
  $stderr.puts "Bundler version 1.10 or later is required. Please update your Bundler"
  raise e
end

gemfile(true) do
  source "https://rubygems.org"
  gem "rails", github: "rails/rails"
  gem "arel", github: "rails/arel"
  gem "sqlite3"
  gem "byebug"
  gem "pry"
end

require "active_record"
require "minitest/autorun"
require "logger"
require "byebug"
require "pry"

#byebug
# 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 :orders do |t|
    t.string :name
  end

  create_table :details do |t|
    t.integer :order_id
  end
end

class Order < ActiveRecord::Base
  has_many :details
  validate :validate_name, if: lambda { |obj| obj.name_changed? }

  def validate_name
    puts "validate_name"
  end
end

class Detail < ActiveRecord::Base
  belongs_to :order
  before_save :update_order

  def update_order
    order.name += ' (updated)'
    order.save
  end
end

class BugTest < Minitest::Test
  def test_association_stuff
    o = Order.create! name: 'An order'
    o.details.create!

    assert_equal 'An order (updated)', o.name
  end
end


------------------------------------------------------------------------------------------------------------------------


begin
  require "bundler/inline"
rescue LoadError => e
  $stderr.puts "Bundler version 1.10 or later is required. Please update your Bundler"
  raise e
end

gemfile(true) do
  source "https://rubygems.org"
  gem "rails", "5.0.2"
  gem "sqlite3"
end

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 :users do |t|
    t.string :first_name
    t.string :last_name
  end
end

class User < ActiveRecord::Base
end

class BugTest < Minitest::Test
  def test_frozen_attributes
    user = User.new(first_name: 'Alex', last_name: 'Kosh')
    refute user.first_name.frozen?

    x = User.new(user.attributes)
    x.inspect

    refute user.first_name.frozen?


    refute user.first_name.frozen?
  end
end

------------------------------------------------------------------------------------------------------------------------


begin
  require "bundler/inline"
rescue LoadError => e
  $stderr.puts "Bundler version 1.10 or later is required. Please update your Bundler"
  raise e
end

gemfile(true) do
  source "https://rubygems.org"
  gem "rails", github: "rails/rails"
  gem "arel", github: "rails/arel"
  gem "sqlite3"
end

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 :companies, force: true do |t|
    t.string "type", limit: 255, null: false
  end
end

class Company < ActiveRecord::Base
end

class Firm < Company
end

class BugTest < Minitest::Test
  def test_association_stuff
    my_firm = Company.create(type: 'Firm')
    assert_equal 'Firm', my_firm.class.name

    my_firm.reload
    assert_equal 'Firm', my_firm.class.name
  end
end