Sorting generic collections when sortable. It can be hard to get stable test results for generic components that use hashing or parallelism. Use sortable elements and applying sortedIfPossible strategically can help

SortedIfPossible.swift

func compare<T: Comparable, U>(_ x: T, _ y: U) -> Bool {
  return x < (y as! T)
}

extension Collection {

  func sortedIfPossible() -> [Element] {
    if isEmpty { return []}

    if Element.self as Any.Type is any Comparable.Type {
      return self.sorted {
        let l = $0 as! any Comparable
        return compare(l, $1)
      }
    }

    if self.first! as Any is (any Comparable, any Comparable) {
      return self.sorted {
        let l = $0 as! (any Comparable, any Comparable)
        let r = $1 as! (any Comparable, any Comparable)
        return compare(l.0, r.0) || !compare(r.0, l.0) && compare(l.1, r.1)
      }
    }

    if self.first! as Any is (any Comparable, Any) {
      return self.sorted {
        let l = $0 as! (any Comparable, Any)
        let r = $1 as! (Any, Any)
        return compare(l.0, r.0)
      }
    }

    return Array(self)
  }

}