gistfile1.rb

unless File.exist?('Gemfile')
  File.write('Gemfile', <<-GEMFILE)
    source 'https://rubygems.org'
    gem 'rails', github: 'rails/rails'
    gem 'arel', github: 'rails/arel'
    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 :gene_claims do |t|
  end

  create_table :gene_claim_categories do |t|
  end

  create_join_table :gene_claims, :gene_claim_categories
end

class GeneClaim < ActiveRecord::Base
  has_and_belongs_to_many :gene_claim_categories
end

class GeneClaimCategory < ActiveRecord::Base
  has_and_belongs_to_many :gene_claims
end

class BugTest < Minitest::Test
  def test_association_stuff
    gene_claim = GeneClaim.create!
    gene_claim_category = GeneClaimCategory.create!
    gene_claim.gene_claim_categories << gene_claim_category
  end
end