require File.expand_path('../helper', __FILE__) require 'rake/thread_pool' class TestRakeTestThreadPool < Rake::TestCase include Rake def test_pool_executes_in_current_thread_for_zero_threads pool = ThreadPool.new(0) f = pool.future { Thread.current } pool.join assert_equal Thread.current, f.value end def test_pool_executes_in_other_thread_for_pool_of_size_one pool = ThreadPool.new(1) f = pool.future { Thread.current } pool.join refute_equal Thread.current, f.value end def test_pool_executes_in_two_other_threads_for_pool_of_size_two pool = ThreadPool.new(2) threads = 2.times.map { pool.future { sleep 0.1 Thread.current } }.each { |f| f.value } refute_equal threads[0], threads[1] refute_equal Thread.current, threads[0] refute_equal Thread.current, threads[1] ensure pool.join end def test_pool_creates_the_correct_number_of_threads pool = ThreadPool.new(2) threads = Set.new t_mutex = Mutex.new 10.times.each do pool.future do sleep 0.02 t_mutex.synchronize { threads << Thread.current } end end pool.join assert_equal 2, threads.count end def test_pool_future_does_not_duplicate_arguments pool = ThreadPool.new(2) obj = Object.new captured = nil pool.future(obj) { |var| captured = var } pool.join assert_equal obj, captured end def test_pool_join_empties_queue pool = ThreadPool.new(2) repeat = 25 repeat.times { pool.future do repeat.times { pool.future do repeat.times { pool.future do end } end } end } pool.join assert_equal( true, pool.__send__(:__queue__).empty?, "queue should be empty") end CustomError = Class.new(StandardError) # test that throwing an exception way down in the blocks propagates # to the top def test_exceptions pool = ThreadPool.new(10) deep_exception_block = lambda do |count| raise CustomError if count < 1 pool.future(count - 1, &deep_exception_block).value end assert_raises(CustomError) do pool.future(2, &deep_exception_block).value end ensure pool.join end def test_pool_prevents_deadlock pool = ThreadPool.new(5) common_dependency_a = pool.future { sleep 0.2 } futures_a = 10.times.map { pool.future { common_dependency_a.value sleep(rand() * 0.01) } } common_dependency_b = pool.future { futures_a.each { |f| f.value } } futures_b = 10.times.map { pool.future { common_dependency_b.value sleep(rand() * 0.01) } } futures_b.each { |f| f.value } pool.join end def test_pool_reports_correct_results pool = ThreadPool.new(7) a = 18 b = 5 c = 3 result = a.times.map do pool.future do b.times.map do pool.future { sleep rand * 0.001; c } end.reduce(0) { |m, f| m + f.value } end end.reduce(0) { |m, f| m + f.value } assert_equal a * b * c, result pool.join end end