bug.rb

#!/usr/bin/env ruby
# To see:
#
# 1. gem bundle
# 2. bin/spec bug.rb
Bundler.require_env

DataMapper.setup(:repo1, 'sqlite3:///tmp/repo1.db')
DataMapper.setup(:repo2, 'sqlite3:///tmp/repo2.db')

class Model1
  include DataMapper::Resource
  def self.default_repository_name() :repo1 end
  property :id, Serial
end

class Model2
  include DataMapper::Resource
  def self.default_repository_name() :repo2 end
  property :id, Serial
end

describe "transactions" do
  it "should be per-adapter" do
    Model1.new.transaction do
      Model2.repository.adapter.current_transaction.should be_nil
    end
  end
end

Gemfile

gem 'dm-core',               '=0.10.2'
gem "data_objects",          '=0.10'
gem "do_sqlite3",            '=0.10'
gem 'rspec', :require_as => 'spec'

potential_fix.rb

#!/usr/bin/env ruby
# To see:
#
# 1. gem bundle
# 2. bin/spec potential_fix.rb
Bundler.require_env

DataMapper.setup(:repo1, 'sqlite3:///tmp/repo1.db')
DataMapper.setup(:repo2, 'sqlite3:///tmp/repo2.db')

class Model1
  include DataMapper::Resource
  def self.default_repository_name() :repo1 end
  property :id, Serial
end

class Model2
  include DataMapper::Resource
  def self.default_repository_name() :repo2 end
  property :id, Serial
end


# A potential fix
module DataMapper
  class Transaction
    module Adapter
      def transactions
        # The replaced implementation is the following:
        #
        # Thread.current[:dm_transactions] ||= []

        Thread.current[:dm_transactions] ||= {}
        Thread.current[:dm_transactions][self] ||= []
      end
    end
  end
end


describe "transactions" do
  it "should be per-adapter" do
    Model1.new.transaction do
      Model2.repository.adapter.current_transaction.should be_nil
    end
  end
end