anchor.diff:                  let result = DisjointSet.inSameSubset disjointSet e e
                   match result with 
                   | Ok (same, _) -> same 
  -                | Bad _ -> true
  +                | Bad _ -> true // out of range 
   
           testPropertyWithConfig {Config.Quick with MaxTest=250}
               "A sequence of union and find operations starting with valid entryIds always returns valid EntryIds." <|
  
positive.code:                 isEmpty disjointSet || checkInSameSubsetAfterUnion()
  
          testPropertyWithConfig {Config.Quick with MaxTest=250}
              "After a union of a b then at most one of a b change their subset EntryId." <|
              fun (disjointSet: DisjointSet) ->
  
                  let checkUnioningBetweenCorrectSubsets = fun _ ->
  
negative.code:                     let size = DisjointSet.size disjointSet
                      let maxIndex = size - 1
                      let makeValidEntry = fun _ -> randomEntry maxIndex
                      let setsCount = subSetsCount disjointSet
  
                      let a = makeValidEntry()
                      let b = makeValidEntry()
  