Test autosave inverse_of system stack error

test_autosave_inverse_of.rb

require 'bundler'
Bundler.setup(:default)

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

# 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 :posts do |t|
    t.string :title
  end

  create_table :comments do |t|
    t.integer :post_id
    t.string :body
  end
end

class Post < ActiveRecord::Base
  has_many :comments, autosave: true
end

class Comment < ActiveRecord::Base
  belongs_to :post, autosave: true
end

class BugTest < Minitest::Test
  def test_association_stuff
    post = Post.create!
    post.comments << Comment.create!

    assert_equal 1, post.comments.count
    assert_equal 1, Comment.count
    assert_equal post.id, Comment.first.post.id

    post.title = "Hello world!"
    post.comments[0].body = "I love Ruby"
    post.save

    assert_equal "Hello world!", post.title
    assert_equal "I love Ruby", post.comments.first.body
  end
end