Ordering behavior of dataflow

OrderingTest.cs

        [Fact]
        public async Task TransformBlockPreserveOrder()
        {
            const int badItem = 89;
            var results = new List<int>();
            var input = Enumerable.Range(1, int.MaxValue);

            var mapBlock = new TransformBlock<int, int>(
                x => x == badItem? throw new Exception("bug") : x,
                new ExecutionDataflowBlockOptions {MaxDegreeOfParallelism = 10});
            var actionBlock = new ActionBlock<int>(x => results.Add(x));
            mapBlock.LinkTo(actionBlock, new DataflowLinkOptions {PropagateCompletion = true});

            var ex = await Assert.ThrowsAsync<AggregateException>(() => Run(mapBlock, actionBlock, input));

            Assert.Equal("bug", ex.InnerException?.Message); // this is ok
            Assert.True(results.Count < badItem); // this fails
            Assert.True(input.Take(results.Count).SequenceEqual(results)); // this fails
        }

        private static async Task Run<T>(ITargetBlock<T> firstBlock, IDataflowBlock lastBlock, IEnumerable<T> input)
        {
            foreach (var item in input)
            {
                var sent = await firstBlock.SendAsync(item);
                if (!sent) break;
            }
            firstBlock.Complete();
            await lastBlock.Completion;
        }