anchor.diff:  
   [<EntryPoint>]
   let main argv = 
  -    [| CodecsShouldLoadProperly; IndexingTests; BooleanQueryCreationTests; RangeQueryCreationTests; SimpleSpatialTests |] 
  +    [| CodecsShouldLoadProperly; PostingsFormatShouldLoadProperly; IndexingTests; BooleanQueryCreationTests; RangeQueryCreationTests; SimpleSpatialTests |] 
       |> Array.iter (fun meth -> exceptionWrapper meth)
       printfn "Done"
       if hasErrors then 1
  
positive.code:         printfn "%A" e
          printfn "------------------------------------------------"
  
  let ShouldHaveFlexCodec50() = Assert.True(Codec.AvailableCodecs().contains("FlexCodec50"), "FlexCodec50 not found.")
  let ShouldHaveFlexCodec410() = Assert.True(Codec.AvailableCodecs().contains("FlexCodec410"), "FlexCodec410 not found.")
  let ShouldHaveFlexPerFieldPostingsFormat() = 
      Assert.True
          (PostingsFormat.AvailablePostingsFormats().contains("PerField40"), "PerField40 Postings format not found.")
  
  let IndexingTest(directory : FlexLucene.Store.Directory) = 
      let analyzer = new StandardAnalyzer()
  
negative.code: 
  [<Fact>]
  let CodecsShouldLoadProperly() = 
      let codecs = Codec.AvailableCodecs()
      printfn "Available Codecs: %A" (codecs)
      ShouldHaveCodec410 |> exceptionWrapper
      ShouldHaveCodec50 |> exceptionWrapper
  
  [<Fact>]
  let PostingsFormatShouldLoadProperly() = 
      printfn "Postings Format : %A" (PostingsFormat.AvailablePostingsFormats())
      Assert.True
          (PostingsFormat.AvailablePostingsFormats().contains("Lucene50"), "Lucene50 Postings format not found.")
  
  [<Fact>]
  let IndexingTests() = 
  