anchor.diff:  open Fantomas.CodeFormatter
   open Fantomas.FormatConfig
   open FsCheck
  -open FsCheck.NUnit
  +open FsUnit
   open Microsoft.FSharp.Compiler.Ast
   open Microsoft.FSharp.Compiler.Range
   
  +let formatConfig = { FormatConfig.Default with StrictMode = true }
  +
   let generateSynMeasure =
       Gen.constant SynMeasure.One
   
  +let generateRange =
  +    Gen.constant range.Zero
  +
   let zero = range.Zero
   
  -let rec generateSynConst size =
  +let generateBasicConst _ =
       Gen.oneof 
           [ 
               Gen.constant SynConst.Unit
  
positive.code: let generateInput = 
      Gen.map (fun ast -> Input (tryFormatAST ast None formatConfig)) generateParsedInput
  
  type Generators = 
      static member ParsedInput() = 
          { new Arbitrary<ParsedInput>() with
                member __.Generator = generateParsedInput
                member __.Shrinker _ = Seq.empty }
      static member Input() = 
          { new Arbitrary<Input>() with
                member __.Generator = generateInput
                member __.Shrinker (Input s) =  
                  let rec shrink = function
                      | [] -> Seq.empty
                      | x::xs ->
                          seq {
                              yield [x]
                              yield xs
                              for xs' in shrink xs -> x::xs'
                          }
                          |> Seq.distinct                    
                  let lines = s.Replace('\r', '\n').Split([|'\n'|], StringSplitOptions.RemoveEmptyEntries) |> Array.toList
                  lines
                  |> shrink
                  |> Seq.map (String.concat "" >> Input)
          }
  
  [<TestFixtureSetUp>]
  let registerFsCheckGenerators() =
  
negative.code: 
  type Input = Input of string
  
  let tryFormatAST ast sourceCode config =
      try
          formatAST ast sourceCode config
  