Found in stress test: https://gist.github.com/alesapin/5cd6b8901488a1f170d5ef389900a534
Report: https://s3.amazonaws.com/clickhouse-test-reports/31158/7fb9a42b119b6c3eba1784caaabde51c1ded3384/stress_tests__debug__actions_.html
{
    auto & output = outputs.front();
    auto & input = inputs.back();
    
    if (output.isFinished())
    {
        input.close();
        return Status::Finished;
    }
    if (!output.canPush())
    {
        input.setNotNeeded();
        return Status::PortFull;
    }
    if (block_end_reached)
    {
        if (need_generate)
        {
            return Status::Ready;
        }
        else
        {
            output.push(std::move(to_push_chunk));