Scalacheck extensions = 2.11 only SBT settings libraryDependencies += "org.cvogt" %% "scalacheck-extensions" % "0.2" Fully automatic tree / class hierarchy generators Usage see GenTreeTest.scala Also see: typelevel/scalacheck#152 Arbitrary instance for arbitrary tuple and function arities (Will be part of official scalacheck >= 1.12.3) See Arities.scala