Deadlock occurs when the pool parent context is canceled with queued tasks in the worker.

[CorentinClabaut]

The following test will block forever:

func TestSubmitWithContextCancelWithIdleTasks(t *testing.T) {

	ctx, cancel := context.WithCancel(context.Background())

	pool := pond.New(1, 5, pond.Context(ctx))

	var doneCount, taskCount int32

	// Submit a long-running, cancellable task
	pool.Submit(func() {
		atomic.AddInt32(&taskCount, 1)
		select {
		case <-ctx.Done():
			return
		case <-time.After(1 * time.Minute):
			atomic.AddInt32(&doneCount, 1)
			return
		}
	})

	// Submit a long-running, cancellable task
	pool.Submit(func() {
		atomic.AddInt32(&taskCount, 1)
		select {
		case <-ctx.Done():
			return
		case <-time.After(1 * time.Minute):
			atomic.AddInt32(&doneCount, 1)
			return
		}
	})

	// Cancel the context
	cancel()

	pool.StopAndWait()

	assertEqual(t, int32(1), atomic.LoadInt32(&taskCount))
	assertEqual(t, int32(0), atomic.LoadInt32(&doneCount))
}