thread-testing.rb

# This is how I'd use threads in rspec to test whether a shared state primitive works as expected 
#(pessimistic database lock,advisory database lock, mutex, etc.)
around do |example|
  die = false
  
  lock_taker = Thread.new do 
    code_that_takes a lock do
      loop do
        break if die
        sleep 0.1 # not strictly necessary but slows CPU churn
      end
    end
  
  example.run  
  die = true
  locker_taker.join
end
  
it "can't get an adivsory lock when alreaedy locked" do  
  code_that_also_takes_a_lock_but_fails
end