This should work always

demo.sh

# jruby 1.7.5.dev (1.9.3p392) 2013-06-20 b13d153 on Java HotSpot(TM) 64-Bit Server VM 1.6.0_45-b06-451-11M4406 [darwin-x86_64]

ruby shutdown.rb
I, [2013-06-20T16:01:33.988000 #64291]  INFO -- : thread start
I, [2013-06-20T16:01:33.996000 #64291]  INFO -- : popping
# this should block because we are joined on the thread which is blocks on the pop
# PASS

ruby shutdown.rb push
I, [2013-06-20T16:01:48.191000 #64308]  INFO -- : thread start
I, [2013-06-20T16:01:48.199000 #64308]  INFO -- : popping
I, [2013-06-20T16:01:48.394000 #64308]  INFO -- : got value: nil
I, [2013-06-20T16:01:48.394000 #64308]  INFO -- : thread finish
# this should complete because we have pushed a value into the queue on which the thread is blocking
# PASS

ruby shutdown.rb kill
I, [2013-06-20T16:02:04.305000 #64327]  INFO -- : thread start
I, [2013-06-20T16:02:04.314000 #64327]  INFO -- : popping
# this should complete because we are joined on the thread which we have just killed
# FAIL

ruby shutdown.rb kill push
I, [2013-06-20T16:02:30.654000 #64348]  INFO -- : thread start
I, [2013-06-20T16:02:30.661000 #64348]  INFO -- : popping
I, [2013-06-20T16:02:30.855000 #64348]  INFO -- : got value: nil
# this should complete because we have both killed the thread and pushed a value into the queue
# PASS

shutdown.rb

require 'logger'
require 'pry'

r, w = IO.pipe
l = Logger.new($stderr)

trap("INFO") {
  w.write(".")
}

Thread.new {
  while r.read(1)
    Thread.list.each do |t|
      puts t.inspect
      puts t.backtrace
      puts "-" * 80
    end
  end
}

q = Queue.new
t = Thread.new {
  l.info "thread start"
  Fiber.new {
    l.info "popping"
    v = q.pop
    l.info "got value: #{v.inspect}"
  }.resume
  l.info "thread finish"
}

kill = ARGV.include?("kill")
push = ARGV.include?("push")

sleep 0.1
t.kill if kill
sleep 0.1
q.push(nil) if push

t.join