anchor.diff:                  testPacketToString (Noop) "6" "noop"
           ]
   
  -        testList "payload to string" [
  -            testCase "empty" <| fun _ ->
  -                testPayloadToString [] "0:" "empty"
  -            testCase "single message" <| fun _ ->
  -                testPayloadToString [Message(String("Hello world"))] "12:4Hello world" "message"
  -            testCase "two messages" <| fun _ ->
  -                testPayloadToString [Message(String("Hello"));Message(String("world"))] "6:4Hello6:4world" "2 messages"
  -            testCase "single binary message" <| fun _ ->
  -                testPayloadToString [Message(Binary([|1uy;2uy;3uy|] |> Segment.ofArray))] "6:b4AQID" "message"
  -        ]
  -
           testList "packet to binary" [
               testCase "open" <| fun _ ->
                   let handshake = { Sid= "xxx";Upgrades=[|"foo";"bar"|];PingTimeout=42; PingInterval=43 }
  
positive.code: let private testPacketToString message expected format =
      Expect.equal (message |> PacketMessage.encodeToString) expected format
  
  let private testPayloadToString messages expected format =
      Expect.equal (Payload(messages) |> Payload.encodeToString) expected format
  
  
negative.code: let appendUtf8 s (arr: int seq) = Seq.concat [arr; utf8 s |> Seq.ofArray]
  
  [<Tests>]
  let encodeTests =
      testList "encode" [
          testList "packet to string" [
              testCase "open" <| fun _ ->
  