Trying to figure out how I can zip both 1-arg functions, and no-arg functions for use in ScalaTest test-fixture "loan" functions.

FunctionZipping.scala

type FixtureFunction[T] = T => Any

implicit class FixtureFunctionZipper[A](f1: FixtureFunction[A] => Any) {
  def zip[B](f2: FixtureFunction[B] => Any): ((A, B) => Any) => Any = { test =>
    f1(a => f2(b => test(a, b)))
  }

  def zip(f2: (Unit => Any) => Any): (A => Any) => Any = { test =>
    f1(a => f2(_ => test(a)))
  }
}

implicit class CBNFixtureFunctionZipper(f1: (Unit => Any) => Any) {
  def zip[A](f2: FixtureFunction[A] => Any): (A => Any) => Any = { test =>
    f1(_ => f2(test))
  }

  def zip(f2: => (Unit => Any) => Any): (=> Any) => Any = { test =>
    f1(_ => f2(_ => test))
  }
}