Columns of same type mixed up during grouping, select and as

I took a TypedDataset of case class A, grouped it, mixing the order of two columns of the same type, resulting in a tupled dataset. I had to do this way, don't ask. To get stuff right again, I selected the columns in the right order again, and finally used .as[A] again to get me back a nice TypedDataset of my type A.

Expected Behaviour: Everything just as it has been, right columns ending up in the right place.

Actual behaviour: The mixed up columns weren't put in the right order by the select I issued at the end.

I suspect the quirk is somewhere within .as[A] but i cannot pinpoint it tbh.

Here a small reproducer:

  import frameless._
  import frameless.syntax._
  import frameless.functions.aggregate.{first, min}

  // create spark session ...

  implicit val sparkSession: SparkSession = session
  case class ConfusingColumns(name: String, company: String, created: Long)
  val data = ConfusingColumns("Joe", "snakeoil Inc.", 123L) ::
    ConfusingColumns("Barb", "ACME", 42L) ::
    ConfusingColumns("Joe", "snakeoil Inc.", 0L) :: Nil
  val ds: TypedDataset[ConfusingColumns] = TypedDataset.create(data)
  val grouped = ds
    .groupBy(
      ds('company)
    )
    .agg(
      first(ds('name)),
      min(ds('created))
    )
  val confused = grouped
    .select(
      grouped('_2),
      grouped('_1),
      grouped('_3)
    )
    .as[ConfusingColumns]
  confused.dataset.show()

Output (compare the case classes in data above):

+-------------+-------+-------+
|         name|company|created|
+-------------+-------+-------+
|snakeoil Inc.|    Joe|      0|
|         ACME|   Barb|     42|
+-------------+-------+-------+

Start with the supplied Scala reproducer and run the grouped, reordered select, and .as[ConfusingColumns] sequence to confirm the column mix-up. Trace the .as[A] conversion and the grouped select entry points to determine where same-typed columns lose their intended order. Done means the resulting ConfusingColumns fields match the original column selections and the reproducer output is corrected.