You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: test_pstore.rb
    path of file: ./repos/jruby/test/mri
    
    the code of the file until where you have to start completion: # frozen_string_literal: true
require 'test/unit'
require 'pstore'
require 'tmpdir'

class PStoreTest < Test::Unit::TestCase
  def setup
    @pstore_file = File.join(Dir.tmpdir, "pstore.tmp.#{Process.pid}")
    @pstore = PStore.new(@pstore_file)
  end

  def teardown
    File.unlink(@pstore_
    
  def test_thread_safe
    q1 = Thread::Queue.new
    assert_raise(PStore::Error) do
      th = Thread.new do
        @pstore.transaction do
          @pstore[:foo] = "bar"
          q1.push true
          sleep
        end
      end
      begin
        q1.pop
        @pstore.transaction {}
      ensure
        th.kill
        th.join
      end
    end