How to keep partitions created before, for group by

I have a DataFrame, which I repartitioned with repartitionByRange or custom-partitioner.
Now, I'm operating Group By on this DataFrame, but the GroupBy causes a new repartition - hash partitioning on the columns selected to group by.

I was wondering how can you keep your original created partitions for GroupBy. Of course the partitions should be partitioned by the selected columns to group by, but how can I determinate a different hashing strategy for group by?