rails-4.1.2.rc2 before_create bug report

gistfile1.rb

# Activate the gem you are reporting the issue against.
gem 'activerecord', '4.1.2.rc1'
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 :posts do |t|
    t.timestamp :published_at

    t.timestamps
  end
end

class Post < ActiveRecord::Base
  before_create do
    self.published_at = self.created_at
  end
end

class BugTest < Minitest::Test
  def test_before_create
    Post.create!

    refute_nil Post.last.published_at,
      "Didn't set 'published_at' on #before_create (because 'created_at' was nil)"
  end
end