Reproduces thread error - run in context of rails app with sidekiq_unique_jobs installed

reproduce_thread_error.rb

#!/usr/bin/env ruby

require 'benchmark'
require_relative '../config/environment'

threads = []

def connection(conn)
  if conn
    conn
  else
    Sidekiq.redis{|con| con }
  end
end
def do_work(conn, i, j)
  connection(conn).watch("foo#{i}#{j}")
  connection(conn).get("foo#{i}#{j}")
  connection(conn).get("foo#{i}#{j}")
  connection(conn).multi do
    connection(conn).set("foo#{i}#{j}", "bar")
    connection(conn).setex("foo#{i}", 100, "#{j}")
  end
  connection(conn).get("foo#{i}#{j}")
  connection(conn).get("foo#{i}")
end
5.times do |a|
  threads << Celluloid::Future.new do |t|
    100.times do |b|
      if rand > 0.5
        do_work(nil, a, b)
      else
        Sidekiq.redis{|conn|
          do_work(conn, a, b)
        }
      end
    end
    puts "Thread #{a} batch done. "
  end
end


threads.map(&:value)
puts "Completed."