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path: root/test/ruby/test_thread.rb
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# -*- coding: us-ascii -*-
require 'test/unit'
require 'thread'
require_relative 'envutil'

class TestThread < Test::Unit::TestCase
  class Thread < ::Thread
    Threads = []
    def self.new(*)
      th = super
      Threads << th
      th
    end
  end

  def setup
    Thread::Threads.clear
  end

  def teardown
    Thread::Threads.each do |t|
      t.kill if t.alive?
      begin
        t.join
      rescue Exception
      end
    end
  end

  def test_main_thread_variable_in_enumerator
    assert_equal Thread.main, Thread.current

    Thread.current.thread_variable_set :foo, "bar"

    thread, value = Fiber.new {
      Fiber.yield [Thread.current, Thread.current.thread_variable_get(:foo)]
    }.resume

    assert_equal Thread.current, thread
    assert_equal Thread.current.thread_variable_get(:foo), value
  end

  def test_thread_variable_in_enumerator
    Thread.new {
      Thread.current.thread_variable_set :foo, "bar"

      thread, value = Fiber.new {
        Fiber.yield [Thread.current, Thread.current.thread_variable_get(:foo)]
      }.resume

      assert_equal Thread.current, thread
      assert_equal Thread.current.thread_variable_get(:foo), value
    }.join
  end

  def test_thread_variables
    assert_equal [], Thread.new { Thread.current.thread_variables }.join.value

    t = Thread.new {
      Thread.current.thread_variable_set(:foo, "bar")
      Thread.current.thread_variables
    }
    assert_equal [:foo], t.join.value
  end

  def test_thread_variable?
    refute Thread.new { Thread.current.thread_variable?("foo") }.join.value
    t = Thread.new {
      Thread.current.thread_variable_set("foo", "bar")
    }.join

    assert t.thread_variable?("foo")
    assert t.thread_variable?(:foo)
    refute t.thread_variable?(:bar)
  end

  def test_thread_variable_strings_and_symbols_are_the_same_key
    t = Thread.new {}.join
    t.thread_variable_set("foo", "bar")
    assert_equal "bar", t.thread_variable_get(:foo)
  end

  def test_thread_variable_frozen
    t = Thread.new { }.join
    t.freeze
    assert_raises(RuntimeError) do
      t.thread_variable_set(:foo, "bar")
    end
  end

  def test_thread_variable_security
    t = Thread.new { sleep }

    assert_raises(SecurityError) do
      Thread.new { $SAFE = 4; t.thread_variable_get(:foo) }.join
    end

    assert_raises(SecurityError) do
      Thread.new { $SAFE = 4; t.thread_variable_set(:foo, :baz) }.join
    end
  end

  def test_mutex_synchronize
    m = Mutex.new
    r = 0
    max = 10
    (1..max).map{
      Thread.new{
        i=0
        while i<max*max
          i+=1
          m.synchronize{
            r += 1
          }
        end
      }
    }.each{|e|
      e.join
    }
    assert_equal(max * max * max, r)
  end

  def test_local_barrier
    dir = File.dirname(__FILE__)
    lbtest = File.join(dir, "lbtest.rb")
    $:.unshift File.join(File.dirname(dir), 'ruby')
    require 'envutil'
    $:.shift
    3.times {
      `#{EnvUtil.rubybin} #{lbtest}`
      assert_not_predicate($?, :coredump?, '[ruby-dev:30653]')
    }
  end

  def test_priority
    c1 = c2 = 0
    t1 = Thread.new { loop { c1 += 1 } }
    t1.priority = 3
    t2 = Thread.new { loop { c2 += 1 } }
    t2.priority = -3
    assert_equal(3, t1.priority)
    assert_equal(-3, t2.priority)
    sleep 0.5
    5.times do
      break if c1 > c2
      sleep 0.1
    end
    t1.kill
    t2.kill
    assert_operator(c1, :>, c2, "[ruby-dev:33124]") # not guaranteed
  end

  def test_new
    assert_raise(ThreadError) do
      Thread.new
    end

    t1 = Thread.new { sleep }
    assert_raise(ThreadError) do
      t1.instance_eval { initialize { } }
    end

    t2 = Thread.new(&method(:sleep).to_proc)
    assert_raise(ThreadError) do
      t2.instance_eval { initialize { } }
    end

  ensure
    t1.kill if t1
    t2.kill if t2
  end

  def test_join
    t = Thread.new { sleep }
    assert_nil(t.join(0.5))

  ensure
    t.kill if t
  end

  def test_join2
    t1 = Thread.new { sleep(1.5) }
    t2 = Thread.new do
      t1.join(1)
    end
    t3 = Thread.new do
      sleep 0.5
      t1.join
    end
    assert_nil(t2.value)
    assert_equal(t1, t3.value)

  ensure
    t1.kill if t1
    t2.kill if t2
    t3.kill if t3
  end

  def test_kill_main_thread
    assert_in_out_err([], <<-INPUT, %w(1), [])
      p 1
      Thread.kill Thread.current
      p 2
    INPUT
  end

  def test_kill_wrong_argument
    bug4367 = '[ruby-core:35086]'
    assert_raise(TypeError, bug4367) {
      Thread.kill(nil)
    }
    o = Object.new
    assert_raise(TypeError, bug4367) {
      Thread.kill(o)
    }
  end

  def test_kill_thread_subclass
    c = Class.new(Thread)
    t = c.new { sleep 10 }
    assert_nothing_raised { Thread.kill(t) }
    assert_equal(nil, t.value)
  end

  def test_exit
    s = 0
    Thread.new do
      s += 1
      Thread.exit
      s += 2
    end.join
    assert_equal(1, s)
  end

  def test_wakeup
    s = 0
    t = Thread.new do
      s += 1
      Thread.stop
      s += 1
    end
    sleep 0.5
    assert_equal(1, s)
    t.wakeup
    sleep 0.5
    assert_equal(2, s)
    assert_raise(ThreadError) { t.wakeup }

  ensure
    t.kill if t
  end

  def test_stop
    assert_in_out_err([], <<-INPUT, %w(2), [])
      begin
        Thread.stop
        p 1
      rescue ThreadError
        p 2
      end
    INPUT
  end

  def test_list
    assert_in_out_err([], <<-INPUT) do |r, e|
      t1 = Thread.new { sleep }
      Thread.pass
      t2 = Thread.new { loop { } }
      Thread.new { }.join
      p [Thread.current, t1, t2].map{|t| t.object_id }.sort
      p Thread.list.map{|t| t.object_id }.sort
    INPUT
      assert_equal(r.first, r.last)
      assert_equal([], e)
    end
  end

  def test_main
    assert_in_out_err([], <<-INPUT, %w(true false), [])
      p Thread.main == Thread.current
      Thread.new { p Thread.main == Thread.current }.join
    INPUT
  end

  def test_abort_on_exception
    assert_in_out_err([], <<-INPUT, %w(false 1), [])
      p Thread.abort_on_exception
      begin
        Thread.new { raise }
        sleep 0.5
        p 1
      rescue
        p 2
      end
    INPUT

    assert_in_out_err([], <<-INPUT, %w(true 2), [])
      Thread.abort_on_exception = true
      p Thread.abort_on_exception
      begin
        Thread.new { raise }
        sleep 0.5
        p 1
      rescue
        p 2
      end
    INPUT

    assert_in_out_err(%w(--disable-gems -d), <<-INPUT, %w(false 2), %r".+")
      p Thread.abort_on_exception
      begin
        Thread.new { raise }
        sleep 0.5
        p 1
      rescue
        p 2
      end
    INPUT

    assert_in_out_err([], <<-INPUT, %w(false true 2), [])
      p Thread.abort_on_exception
      begin
        t = Thread.new { sleep 0.5; raise }
        t.abort_on_exception = true
        p t.abort_on_exception
        sleep 1
        p 1
      rescue
        p 2
      end
    INPUT
  end

  def test_status_and_stop_p
    a = ::Thread.new { raise("die now") }
    b = Thread.new { Thread.stop }
    c = Thread.new { Thread.exit }
    e = Thread.current
    sleep 0.5

    assert_equal(nil, a.status)
    assert_predicate(a, :stop?)

    assert_equal("sleep", b.status)
    assert_predicate(b, :stop?)

    assert_equal(false, c.status)
    assert_match(/^#<TestThread::Thread:.* dead>$/, c.inspect)
    assert_predicate(c, :stop?)

    es1 = e.status
    es2 = e.stop?
    assert_equal(["run", false], [es1, es2])

  ensure
    a.kill if a
    b.kill if b
    c.kill if c
  end

  def test_safe_level
    t = Thread.new { $SAFE = 3; sleep }
    sleep 0.5
    assert_equal(0, Thread.current.safe_level)
    assert_equal(3, t.safe_level)

  ensure
    t.kill if t
  end

  def test_thread_local
    t = Thread.new { sleep }

    assert_equal(false, t.key?(:foo))

    t["foo"] = "foo"
    t["bar"] = "bar"
    t["baz"] = "baz"

    assert_equal(true, t.key?(:foo))
    assert_equal(true, t.key?("foo"))
    assert_equal(false, t.key?(:qux))
    assert_equal(false, t.key?("qux"))

    assert_equal([:foo, :bar, :baz], t.keys)

  ensure
    t.kill if t
  end

  def test_thread_local_security
    t = Thread.new { sleep }

    assert_raise(SecurityError) do
      Thread.new { $SAFE = 4; t[:foo] }.join
    end

    assert_raise(SecurityError) do
      Thread.new { $SAFE = 4; t[:foo] = :baz }.join
    end

    assert_raise(RuntimeError) do
      Thread.new do
        Thread.current[:foo] = :bar
        Thread.current.freeze
        Thread.current[:foo] = :baz
      end.join
    end
  end

  def test_select_wait
    assert_nil(IO.select(nil, nil, nil, 1))
    t = Thread.new do
      IO.select(nil, nil, nil, nil)
    end
    sleep 0.5
    t.kill
  end

  def test_mutex_deadlock
    m = Mutex.new
    m.synchronize do
      assert_raise(ThreadError) do
        m.synchronize do
          assert(false)
        end
      end
    end
  end

  def test_mutex_interrupt
    m = Mutex.new
    m.lock
    t = Thread.new do
      m.lock
      :foo
    end
    sleep 0.5
    t.kill
    assert_nil(t.value)
  end

  def test_mutex_illegal_unlock
    m = Mutex.new
    m.lock
    assert_raise(ThreadError) do
      Thread.new do
        m.unlock
      end.join
    end
  end

  def test_mutex_fifo_like_lock
    m1 = Mutex.new
    m2 = Mutex.new
    m1.lock
    m2.lock
    m1.unlock
    m2.unlock
    assert_equal(false, m1.locked?)
    assert_equal(false, m2.locked?)

    m3 = Mutex.new
    m1.lock
    m2.lock
    m3.lock
    m1.unlock
    m2.unlock
    m3.unlock
    assert_equal(false, m1.locked?)
    assert_equal(false, m2.locked?)
    assert_equal(false, m3.locked?)
  end

  def test_mutex_trylock
    m = Mutex.new
    assert_equal(true, m.try_lock)
    assert_equal(false, m.try_lock, '[ruby-core:20943]')

    Thread.new{
      assert_equal(false, m.try_lock)
    }.join

    m.unlock
  end

  def test_recursive_outer
    arr = []
    obj = Struct.new(:foo, :visited).new(arr, false)
    arr << obj
    def obj.hash
      self[:visited] = true
      super
      raise "recursive_outer should short circuit intermediate calls"
    end
    assert_nothing_raised {arr.hash}
    assert(obj[:visited], "obj.hash was not called")
  end

  def test_thread_instance_variable
    bug4389 = '[ruby-core:35192]'
    assert_in_out_err([], <<-INPUT, %w(), [], bug4389)
      class << Thread.current
        @data = :data
      end
    INPUT
  end

  def test_no_valid_cfp
    skip 'with win32ole, cannot run this testcase because win32ole redefines Thread#intialize' if defined?(WIN32OLE)
    bug5083 = '[ruby-dev:44208]'
    assert_equal([], Thread.new(&Module.method(:nesting)).value)
    error = assert_raise(RuntimeError) do
      Thread.new(:to_s, &Module.method(:undef_method)).join
    end
    assert_equal("Can't call on top of Fiber or Thread", error.message, bug5083)
  end

  def make_async_interrupt_timing_test_thread1 flag
    r = []
    ready_p = false
    th = Thread.new{
      begin
        Thread.async_interrupt_timing(RuntimeError => flag){
          begin
            ready_p = true
            sleep 0.5
          rescue
            r << :c1
          end
        }
      rescue
        r << :c2
      end
    }
    Thread.pass until ready_p
    th.raise
    begin
      th.join
    rescue
      r << :c3
    end
    r
  end

  def test_async_interrupt_timing
    [[:defer, :c2],
     [:immediate, :c1],
     [:on_blocking, :c1]].each{|(flag, c)|
      assert_equal([flag, c], [flag] + make_async_interrupt_timing_test_thread1(flag))
    }
    # TODO: complex cases are needed.
  end

  def test_async_interrupt_timing_invalid_argument
    assert_raise(ArgumentError) {
      Thread.async_interrupt_timing(RuntimeError => :immediate) # no block
    }
    assert_raise(ArgumentError) {
      Thread.async_interrupt_timing(RuntimeError => :never) {} # never?
    }
    assert_raise(TypeError) {
      Thread.async_interrupt_timing([]) {} # array
    }
  end

  def for_test_async_interrupt_with_return
    Thread.async_interrupt_timing(Object => :defer){
      Thread.current.raise RuntimeError.new("have to be rescured")
      return
    }
  rescue
  end

  def test_async_interrupt_with_return
    assert_nothing_raised do
      for_test_async_interrupt_with_return
      _dummy_for_check_ints=nil
    end
  end

  def test_async_interrupt_with_break
    assert_nothing_raised do
      begin
        Thread.async_interrupt_timing(Object => :defer){
          Thread.current.raise RuntimeError.new("have to be rescured")
          break
        }
      rescue
      end
      _dummy_for_check_ints=nil
    end
  end

  def test_async_interrupt_blocking
    r=:ng
    e=Class.new(Exception)
    th_s = Thread.current
    begin
      th = Thread.start{
        Thread.async_interrupt_timing(Object => :on_blocking){
          begin
            Thread.current.raise RuntimeError
            r=:ok
            sleep
          ensure
            th_s.raise e
          end
        }
      }
      sleep 1
      r=:ng
      th.raise RuntimeError
      th.join
    rescue e
    end
    assert_equal(:ok,r)
  end

  def test_async_interrupt_and_io
    assert_in_out_err([], <<-INPUT, %w(ok), [])
      th_waiting = true

      t = Thread.new {
        Thread.async_interrupt_timing(RuntimeError => :on_blocking) {
          nil while th_waiting
          # async interrupt should be raised _before_ writing puts arguments
          puts "ng"
        }
      }

      sleep 0.1
      t.raise RuntimeError
      th_waiting = false
      t.join rescue nil
      puts "ok"
    INPUT
  end

  def test_async_interrupt_and_p
    assert_in_out_err([], <<-INPUT, %w(:ok :ok), [])
      th_waiting = true

      t = Thread.new {
        Thread.async_interrupt_timing(RuntimeError => :on_blocking) {
          nil while th_waiting
          # p shouldn't provide interruptible point
          p :ok
          p :ok
        }
      }

      sleep 0.1
      t.raise RuntimeError
      th_waiting = false
      t.join rescue nil
    INPUT
  end

  def test_async_interrupted?
    q = Queue.new
    Thread.async_interrupt_timing(RuntimeError => :defer){
      th = Thread.new{
        q.push :e
        begin
          begin
            sleep 0.5
          rescue => e
            q.push :ng1
          end
          begin
            Thread.async_interrupt_timing(Object => :immediate){} if Thread.async_interrupted?
          rescue => e
            q.push :ok
          end
        rescue => e
          q.push :ng2
        ensure
          q.push :ng3
        end
      }
      q.pop
      th.raise
      th.join
      assert_equal(:ok, q.pop)
    }
  end

  def test_thread_timer_and_ensure
    assert_normal_exit(<<_eom, 'r36492', timeout: 3)
    flag = false
    t = Thread.new do
      begin
        sleep
      ensure
        1 until flag
      end
    end

    Thread.pass until t.status == "sleep"

    t.kill
    t.alive? == true
    flag = true
    t.join
_eom
  end

  def test_uninitialized
    c = Class.new(Thread)
    c.class_eval { def initialize; end }
    assert_raise(ThreadError) { c.new.start }
  end

  def test_backtrace
    Thread.new{
      assert_equal(Array, Thread.main.backtrace.class)
    }.join

    t = Thread.new{}
    t.join
    assert_equal(nil, t.backtrace)
  end

  def test_thread_timer_and_interrupt
    bug5757 = '[ruby-dev:44985]'
    t0 = Time.now.to_f
    pid = nil
    cmd = 'r,=IO.pipe; Thread.start {Thread.pass until Thread.main.stop?; puts; STDOUT.flush}; r.read'
    opt = {}
    opt[:new_pgroup] = true if /mswin|mingw/ =~ RUBY_PLATFORM
    s, _err = EnvUtil.invoke_ruby(['-e', cmd], "", true, true, opt) do |in_p, out_p, err_p, cpid|
      out_p.gets
      pid = cpid
      Process.kill(:SIGINT, pid)
      Process.wait(pid)
      [$?, err_p.read]
    end
    t1 = Time.now.to_f
    assert_equal(pid, s.pid, bug5757)
    unless /mswin|mingw/ =~ RUBY_PLATFORM
      # status of signal is not supported on Windows
      assert_equal([false, true, false, Signal.list["INT"]],
                   [s.exited?, s.signaled?, s.stopped?, s.termsig],
                   "[s.exited?, s.signaled?, s.stopped?, s.termsig]")
    end
    assert_in_delta(t1 - t0, 1, 1, bug5757)
  end

  def test_thread_join_in_trap
    assert_nothing_raised{
      t = Thread.new{ sleep 0.2; Process.kill(:INT, $$) }

      Signal.trap :INT do
        t.join
      end

      t.join
    }

    assert_equal(:normal_end,
                 begin
                   t = Thread.new{ sleep 0.2; Process.kill(:INT, $$); :normal_end }

                   Signal.trap :INT do
                     t.value
                   end
                   t.value
                 end
                 )
  end

  def test_thread_join_current
    assert_raises(ThreadError) do
      Thread.current.join
    end
  end

  def test_thread_join_main_thread
    assert_raises(ThreadError) do
      Thread.new(Thread.current) {|t|
        t.join
      }.join
    end
  end

  def test_main_thread_status_at_exit
    assert_in_out_err([], <<-INPUT, %w(false), [])
Thread.new(Thread.current) {|mth|
  begin
    sleep 0.1
  ensure
    p mth.alive?
  end
}
    INPUT
  end

  def test_thread_status_in_trap
    # when running trap handler, Thread#status must show "run"
    # Even though interrupted from sleeping function
    assert_in_out_err([], <<-INPUT, %w(sleep run), [])
      Signal.trap(:INT) {
        puts Thread.current.status
      }

      Thread.new(Thread.current) {|mth|
        sleep 0.01
        puts mth.status
        Process.kill(:INT, $$)
      }
      sleep 0.1
    INPUT
  end

  # Bug #7450
  def test_thread_status_raise_after_kill
    ary = []

    t = Thread.new {
      begin
        ary << Thread.current.status
        sleep #1
      ensure
        begin
          ary << Thread.current.status
          sleep #2
        ensure
          ary << Thread.current.status
        end
      end
    }

    begin
      sleep 0.01
      t.kill  # wake up sleep #1
      sleep 0.01
      t.raise "wakeup" # wake up sleep #2
      sleep 0.01
      assert_equal(ary, ["run", "aborting", "aborting"])
    ensure
      t.join rescue nil
    end
  end

  def test_mutex_owned
    mutex = Mutex.new

    assert_equal(mutex.owned?, false)
    mutex.synchronize {
      # Now, I have the mutex
      assert_equal(mutex.owned?, true)
    }
    assert_equal(mutex.owned?, false)
  end

  def test_mutex_owned2
    begin
      mutex = Mutex.new
      th = Thread.new {
        # lock forever
        mutex.lock
        sleep
      }

      sleep 0.01 until th.status == "sleep"
      # acquired another thread.
      assert_equal(mutex.locked?, true)
      assert_equal(mutex.owned?, false)
    ensure
      th.kill if th
    end
  end

  def invoke_rec script, vm_stack_size, machine_stack_size, use_length = true
    env = {}
    env['RUBY_THREAD_VM_STACK_SIZE'] = vm_stack_size.to_s if vm_stack_size
    env['RUBY_THREAD_MACHINE_STACK_SIZE'] = machine_stack_size.to_s if machine_stack_size
    out, = EnvUtil.invoke_ruby([env, '-e', script], '', true, true)
    use_length ? out.length : out
  end

  def test_stack_size
    h_default = eval(invoke_rec('p RubyVM::DEFAULT_PARAMS', nil, nil, false))
    h_0 = eval(invoke_rec('p RubyVM::DEFAULT_PARAMS', 0, 0, false))
    h_large = eval(invoke_rec('p RubyVM::DEFAULT_PARAMS', 1024 * 1024 * 10, 1024 * 1024 * 10, false))

    assert_operator(h_default[:thread_vm_stack_size], :>, h_0[:thread_vm_stack_size],
                    "0 thread_vm_stack_size")
    assert_operator(h_default[:thread_vm_stack_size], :<, h_large[:thread_vm_stack_size],
                    "large thread_vm_stack_size")
    assert_operator(h_default[:thread_machine_stack_size], :>=, h_0[:thread_machine_stack_size],
                    "0 thread_machine_stack_size")
    assert_operator(h_default[:thread_machine_stack_size], :<=, h_large[:thread_machine_stack_size],
                    "large thread_machine_stack_size")

    # check VM machine stack size
    script = 'def rec; print "."; STDOUT.flush; rec; end; rec'
    size_default = invoke_rec script, nil, nil
    assert_operator(size_default, :>, 0, "default size")
    size_0 = invoke_rec script, 0, nil
    assert_operator(size_default, :>, size_0, "0 size")
    size_large = invoke_rec script, 1024 * 1024 * 10, nil
    assert_operator(size_default, :<, size_large, "large size")

    return if /mswin|mingw/ =~ RUBY_PLATFORM

    # check machine stack size
    # Note that machine stack size may not change size (depend on OSs)
    script = 'def rec; print "."; STDOUT.flush; 1.times{1.times{1.times{rec}}}; end; Thread.new{rec}.join'
    vm_stack_size = 1024 * 1024
    size_default = invoke_rec script, vm_stack_size, nil
    size_0 = invoke_rec script, vm_stack_size, 0
    assert_operator(size_default, :>=, size_0, "0 size")
    size_large = invoke_rec script, vm_stack_size, 1024 * 1024 * 10
    assert_operator(size_default, :<=, size_large, "large size")
  end
end