patchInPlace throws a class cast exception

[Ichoran]

java.lang.ClassCastException: strawman.collection.immutable.Nil$ cannot be cast to strawman.collection.immutable.$colon$colon
strawman.collection.mutable.ListBuffer.locate(ListBuffer.scala:153)
strawman.collection.mutable.ListBuffer.patchInPlace(ListBuffer.scala:272)

The call was to ArrayBuffer.empty[Int].patch(-1, ArrayBuffer.empty[Int], -1), but this shouldn't happen regardless.

[marcelocenerine]

The call must have been ListBuffer.empty[Int].patchInPlace(-1, ListBuffer.empty[Int], -1). This is probably caused by the fact that the from parameter is not normalized.