Demonstration of issue with MonitorMixin on Ruby 1.8

monitor-test.rb

#!/usr/bin/env ruby

require 'thread'
require 'rubygems'
require 'monitor'

class Dummy
  include MonitorMixin

  def sync
    self.synchronize { }
  end
end

q = Queue.new

t = Thread.new do
  puts "bmw: before sync"
  Dummy.new.sync
  puts "bmw: after sync"
  q.push 'go ahead, other thread'
  sleep
end

q.pop # wait until thread pushes to q

t.run
t.join