anchor.diff:          {
               Debug = false
               Parallel = true
  +            ParallelWorkers = 0
               Filter = ""
               FilterTestCase = ""
               FailOnFocusedTests = true
  
positive.code: 
      override this.ToString() =
          let append (s: string) (sb: StringBuilder) = sb.Append s
          let appendIfTrue p s sb =
              if p then append s sb else sb
          let appendIfNotNullOrWhiteSpace p s (sb: StringBuilder) =
              if String.IsNullOrWhiteSpace p |> not
              then sprintf "%s%s " s p |> sb.Append
              else sb
          let appendList list s (sb: StringBuilder) =
              let filtered = list |> List.filter (String.IsNullOrWhiteSpace >> not)
  
negative.code:         StringBuilder()
          |> appendIfTrue this.Debug "--debug "
          |> appendIfTrue this.Parallel "--parallel "
          |> appendIfNotEqual 0 this.ParallelWorkers "--parallel-workers "
          |> appendIfTrue this.FailOnFocusedTests "--fail-on-focused-tests "
          |> appendIfTrue this.Summary "--summary "
          |> appendIfTrue this.SummaryLocation "--summary-location "
          |> appendIfTrue (not this.Parallel) "--sequential "
          |> appendIfTrue this.PrintVersion "--version "
          |> appendIfTrue this.ListTests "--list-tests "
  