s_41073.rb

# frozen_string_literal: true

require "bundler/inline"

gemfile(true) do
  source "https://rubygems.org"

  git_source(:github) { |repo| "https://github.com/#{repo}.git" }

  gem "rails", path: "."
  gem "pg"
end

require "active_record"
require "minitest/autorun"
require "logger"

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

ActiveRecord::Schema.define do
  create_table :posts, force: true do |t|
  end

  create_table :comments, force: true do |t|
    t.integer :post_id
  end
end

class Post < ActiveRecord::Base
  has_many :comments
end

class Comment < ActiveRecord::Base
  belongs_to :post
end

class BugTest < Minitest::Test
  def test_association_stuff
    post = Post.create!
    post2 = Post.create!
    post3 = Post.create!

    post.comments += [Comment.create!, Comment.create!, Comment.create!]
    post2.comments += [Comment.create!,Comment.create!]
    post3.comments += [Comment.create!]

    assert_equal 3, post.comments.count
    assert_equal 6, Comment.count

    assert_equal({ 1 => 3, 2 => 2, 3 => 1 }, Comment.group(:post_id).count)
  end
end