show_limit %q{
  threads = []
  begin
    threads << Thread.new{sleep}

    raise Exception, "skipping" if threads.count >= 10_000
  rescue Exception => error
    puts "Thread count: #{threads.count} (#{error})"
    break
  end while true
} if false # disable to pass CI

assert_equal %q{ok}, %q{
  Thread.new{
  }.join
  :ok
}
assert_equal %q{ok}, %q{
  Thread.new{
    :ok
  }.value
}
assert_equal %q{ok}, %q{
begin
  v = 0
  (1..200).map{|i|
    Thread.new{
      i
    }
  }.each{|t|
    v += t.value
  }
  v == 20100 ? :ok : v
rescue ThreadError => e
  :ok if /can't create Thread/ =~ e.message
end
}
assert_equal %q{ok}, %q{
begin
  :ok if 5000 == 5000.times{|e|
    (1..2).map{
      Thread.new{
      }
    }.each{|e|
      e.join()
    }
  }
rescue ThreadError => e
  /can't create Thread/ =~ e.message ? :ok : e.message
end
}
assert_equal %q{ok}, %q{
begin
  :ok if 5000 == 5000.times{|e|
    (1..2).map{
      Thread.new{
      }
    }.each{|e|
      e.join(1000000000)
    }
  }
rescue ThreadError => e
  /can't create Thread/ =~ e.message ? :ok : e.message
end
}
assert_equal %q{ok}, %q{
begin
  :ok if 5000 == 5000.times{
    t = Thread.new{}
    while t.alive?
      Thread.pass
    end
  }
rescue NoMemoryError
  :ok
end
}
assert_equal %q{100}, %q{
  100.times{
    Thread.new{loop{Thread.pass}}
  }
}
assert_equal %q{ok}, %q{
  Thread.new{
    :ok
  }.join.value
}
assert_equal %q{ok}, %q{
  begin
    Thread.new{
      raise "ok"
    }.join
  rescue => e
    e
  end
}
assert_equal %q{ok}, %q{
  ans = nil
  t = Thread.new{
    begin
      sleep 0.5
    ensure
      ans = :ok
    end
  }
  Thread.pass until t.stop?
  t.kill
  t.join
  ans
}
assert_equal %q{ok}, %q{
  t = Thread.new{
    sleep
  }
  sleep 0.1
  t.raise
  begin
    t.join
    :ng
  rescue
    :ok
  end
}
assert_equal %q{ok}, %q{
  t = Thread.new{
    loop{}
  }
  Thread.pass
  t.raise
  begin
    t.join
    :ng
  rescue
    :ok
  end
}
assert_equal %q{ok}, %q{
  t = Thread.new{
  }
  Thread.pass
  t.join
  t.raise # raise to exited thread
  begin
    t.join
    :ok
  rescue
    :ng
  end
}
assert_equal %q{run}, %q{
  t = Thread.new{
    loop{}
  }
  st = t.status
  t.kill
  st
}
assert_equal %q{sleep}, %q{
  t = Thread.new{
    sleep
  }
  sleep 0.1
  st = t.status
  t.kill
  st
}
assert_equal %q{false}, %q{
  t = Thread.new{
  }
  t.kill
  sleep 0.1
  t.status
}
assert_equal %q{[ThreadGroup, true]}, %q{
  ptg = Thread.current.group
  Thread.new{
    ctg = Thread.current.group
    [ctg.class, ctg == ptg]
  }.value
}
assert_equal %q{[1, 1]}, %q{
  thg = ThreadGroup.new

  t = Thread.new{
    thg.add Thread.current
    sleep
  }
  sleep 0.1
  [thg.list.size, ThreadGroup::Default.list.size]
}
assert_equal %q{true}, %q{
  thg = ThreadGroup.new

  t = Thread.new{sleep 5}
  thg.add t
  thg.list.include?(t)
}
assert_equal %q{[true, nil, true]}, %q{
  /a/ =~ 'a'
  $a = $~
  Thread.new{
    $b = $~
    /b/ =~ 'b'
    $c = $~
  }.join
  $d = $~
  [$a == $d, $b, $c != $d]
}
assert_equal %q{11}, %q{
  Thread.current[:a] = 1
  Thread.new{
    Thread.current[:a] = 10
    Thread.pass
    Thread.current[:a]
  }.value + Thread.current[:a]
}
assert_normal_exit %q{
  begin
    100.times do |i|
      begin
        th = Thread.start(Thread.current) {|u| u.raise }
        raise
      rescue
      ensure
        th.join
      end
    end
  rescue
  end
}, '[ruby-dev:31371]'

assert_equal 'true', %{
  t = Thread.new { loop {} }
  begin
    pid = fork {
      exit t.status != "run"
    }
    Process.wait pid
    $?.success?
  rescue NotImplementedError
    true
  end
}

assert_equal 'true', %{
  Thread.new{}.join
  begin
    Process.waitpid2 fork{
      Thread.new{
        sleep 0.1
      }.join
    }
    true
  rescue NotImplementedError
    true
  end
}

assert_equal 'ok', %{
  open("zzz_t1.rb", "w") do |f|
    f.puts <<-END
      begin
        Thread.new { fork { GC.start } }.join
        pid, status = Process.wait2
        $result = status.success? ? :ok : :ng
      rescue NotImplementedError
        $result = :ok
      end
    END
  end
  require "./zzz_t1.rb"
  $result
}

assert_finish 3, %{
  th = Thread.new {sleep 0.2}
  th.join(0.1)
  th.join
}

assert_finish 3, %{
  require 'timeout'
  th = Thread.new {sleep 0.2}
  begin
    Timeout.timeout(0.1) {th.join}
  rescue Timeout::Error
  end
  th.join
}

assert_normal_exit %q{
  STDERR.reopen(STDOUT)
  exec "/"
}

assert_normal_exit %q{
  (0..10).map {
    Thread.new {
     10000.times {
        Object.new.to_s
      }
    }
  }.each {|t|
    t.join
  }
} unless rjit_enabled? # flaky

assert_equal 'ok', %q{
  def m
    t = Thread.new { while true; // =~ "" end }
    sleep 0.01
    10.times {
      if /((ab)*(ab)*)*(b)/ =~ "ab"*7
        return :ng if !$4
        return :ng if $~.size != 5
      end
    }
    :ok
  ensure
    Thread.kill t
  end
  m
}, '[ruby-dev:34492]'

assert_normal_exit %q{
  g = enum_for(:local_variables)
  loop { g.next }
}, '[ruby-dev:34128]'

assert_normal_exit %q{
  g = enum_for(:block_given?)
  loop { g.next }
}, '[ruby-dev:34128]'

assert_normal_exit %q{
  g = enum_for(:binding)
  loop { g.next }
}, '[ruby-dev:34128]'

assert_normal_exit %q{
  g = "abc".enum_for(:scan, /./)
  loop { g.next }
}, '[ruby-dev:34128]'

assert_normal_exit %q{
  g = Module.enum_for(:new)
  loop { g.next }
}, '[ruby-dev:34128]'

assert_normal_exit %q{
  Thread.new("foo", &Object.method(:class_eval)).join
}, '[ruby-dev:34128]'

assert_equal 'ok', %q{
  begin
    Thread.new { Thread.stop }
    Thread.stop
    :ng
  rescue Exception
    :ok
  end
}

assert_equal 'ok', %q{
  begin
    m1, m2 = Thread::Mutex.new, Thread::Mutex.new
    f1 = f2 = false
    Thread.new { m1.lock; f2 = true; sleep 0.001 until f1; m2.lock }
    m2.lock; f1 = true; sleep 0.001 until f2; m1.lock
    :ng
  rescue Exception
    :ok
  end
}

assert_equal 'ok', %q{
  m = Thread::Mutex.new
  Thread.new { m.lock }; sleep 0.1; m.lock
  :ok
}

assert_equal 'ok', %q{
  m = Thread::Mutex.new
  Thread.new { m.lock }; m.lock
  :ok
}

assert_equal 'ok', %q{
  m = Thread::Mutex.new
  Thread.new { m.lock }.join; m.lock
  :ok
}

assert_equal 'ok', %q{
  m = Thread::Mutex.new
  Thread.new { m.lock; sleep 0.2 }
  sleep 0.1; m.lock
  :ok
}

assert_equal 'ok', %q{
  m = Thread::Mutex.new
  Thread.new { m.lock; sleep 0.2; m.unlock }
  sleep 0.1; m.lock
  :ok
}

assert_equal 'ok', %q{
  t = Thread.new {`echo`}
  t.join
  $? ? :ng : :ok
}, '[ruby-dev:35414]'

assert_equal 'ok', %q{
  begin
    100.times{
      (1..100).map{ Thread.new(true) {|x| x == false } }.each{|th| th.join}
    }
  rescue NoMemoryError, StandardError
  end
  :ok
}

assert_equal 'ok', %{
  open("zzz_t2.rb", "w") do |f|
    f.puts <<-'end;' # do
      begin
        m = Thread::Mutex.new
        parent = Thread.current
        th1 = Thread.new { m.lock; sleep }
        sleep 0.01 until th1.stop?
        Thread.new do
          sleep 0.01 until parent.stop?
          begin
            fork { GC.start }
          rescue Exception
            parent.raise $!
          end
          th1.run
        end
        m.lock
        pid, status = Process.wait2
        $result = status.success? ? :ok : :ng
      rescue NotImplementedError
        $result = :ok
      end
    end;
  end
  require "./zzz_t2.rb"
  $result
}

assert_finish 3, %q{
  require 'thread'

  lock = Thread::Mutex.new
  cond = Thread::ConditionVariable.new
  t = Thread.new do
    lock.synchronize do
      cond.wait(lock)
    end
  end

  begin
    pid = fork do
      # Child
      STDOUT.write "This is the child process.\n"
      STDOUT.write "Child process exiting.\n"
    end
    Process.waitpid(pid)
  rescue NotImplementedError
  end
}, '[ruby-core:23572]'

assert_equal 'ok', %q{
  begin
    Process.waitpid2(fork {})[1].success? ? 'ok' : 'ng'
  rescue NotImplementedError
    'ok'
  end
}

assert_equal 'foo', %q{
  i = 0
  Thread.start {sleep 1; exit!}
  f = proc {|s, c| /#{c.call; s}/o }
  th2 = Thread.new {
    sleep 0.01 until i == 1
    i = 2
    f.call("bar", proc {sleep 2});
    nil
  }
  th1 = Thread.new {
    f.call("foo", proc {i = 1; sleep 0.01 until i == 2; sleep 0.01})
    nil
  }
  [th1, th2].each {|t| t.join }
  GC.start
  f.call.source
} unless rjit_enabled? # flaky
assert_normal_exit %q{
  class C
    def inspect
      sleep 0.5
      'C!!'
    end
  end
  Thread.new{
    loop{
      p C.new
    }
  }
  sleep 0.1
}, timeout: 5