Breaking change in v1.4

[dlidstrom]

It seems version 1.4 introduced a breaking change. This can be reproduced with the script below. With v1.3.13 it is able to deserialise the file, but with v1.4.34 it fails.

Is there a fix to make this work with v1.4?

Game.json

{
  "lane": 1,
  "playedGame": {
    "holes": 0,
    "frames": [
      [
        "Strike",
        19
      ],
      [
        {
          "Case": "Miss",
          "Fields": [
            "Seven",
            "Two"
          ]
        },
        28
      ],
      [
        {
          "Case": "Spare",
          "Fields": [
            "Nine"
          ]
        },
        48
      ],
      [
        "Strike",
        68
      ],
      [
        {
          "Case": "Spare",
          "Fields": [
            "Nine"
          ]
        },
        87
      ],
      [
        {
          "Case": "Spare",
          "Fields": [
            "Nine"
          ]
        },
        106
      ],
      [
        {
          "Case": "Spare",
          "Fields": [
            "Nine"
          ]
        },
        122
      ],
      [
        {
          "Case": "Spare",
          "Fields": [
            "Six"
          ]
        },
        139
      ],
      [
        {
          "Case": "Miss",
          "Fields": [
            "Seven",
            "One"
          ]
        },
        147
      ],
      [
        {
          "Case": "Miss",
          "Fields": [
            "Seven",
            "One"
          ]
        },
        155
      ]
    ],
    "spares": 5,
    "strikes": 2,
    "totalScore": 155,
    "finishedDate": "2025-03-26T06:00:25",
    "singleSpares": 4,
    "spareAttempts": 8,
    "strikesOnStrike": 0,
    "singleSpareAttempts": 4,
    "strikesOnStrikeAttempts": 2
  },
  "playerName": "Stoffe",
  "imagePartName": "/01/2025-03-26_060025.jpg"
}

Game.fsx

#r "nuget: FSharp.SystemTextJson, 1.3.13" // works
//#r "nuget: FSharp.SystemTextJson, 1.4.34" // fails

open System
open System.IO

type FrameRollType =
  | Empty
  | Strike
  | Spare
  | Nine
  | Eight
  | EightHole
  | Seven
  | SevenHole
  | Six
  | SixHole
  | Five
  | FiveHole
  | Four
  | FourHole
  | Three
  | Two
  | One
  | Miss
  | Skip
  | Restart
  | Unknown

type LastFrameType =
    | DoubleStrike of FrameRollType
    | StrikeSpare of FrameRollType
    | StrikeMiss of FrameRollType * FrameRollType
    | SpareExtra of FrameRollType * FrameRollType
    | Miss of FrameRollType * FrameRollType
type FrameRoll =
    | Strike
    | Spare of FrameRollType
    | Miss of FrameRollType * FrameRollType
    | LastFrame of LastFrameType
type Frame = FrameRoll * int

type PlayedGame = {
  Frames: Frame list
  TotalScore: int
  Strikes: int
  StrikesOnStrike: int
  StrikesOnStrikeAttempts: int
  Spares: int
  SpareAttempts: int
  Holes: int
  SingleSpares: int
  SingleSpareAttempts: int
  FinishedDate: DateTime
}

type PlayerGame =
  { PlayerName: string
    Lane: int
    PlayedGame: PlayedGame }

module Json =
  open System.Text.Json
  open System.Text.Json.Serialization
  let opts = JsonSerializerOptions(
    WriteIndented = true,
    PropertyNameCaseInsensitive = true,
    PropertyNamingPolicy = JsonNamingPolicy.CamelCase)
  JsonFSharpOptions()
    .WithUnionUnwrapFieldlessTags()
    .AddToJsonSerializerOptions(opts)

  let fromJson<'a> (s: string) = JsonSerializer.Deserialize<'a>(s, opts)

Json.fromJson<PlayerGame>(File.ReadAllText "Game.json")

[Tarmil]

Ah, I see the issue. With the addition of support for enum-like unions (such as your FrameRollType) as dictionary keys, they now take into consideration the PropertyNamingPolicy. But this should only be the case when reading them as dictionary keys, not as values. And there might also be a discrepancy in taking into consideration PropertyNameCaseInsensitive. I'll investigate further.

[Tarmil]

This is fixed in v1.4.36.

[dlidstrom]

Thank you!

[dlidstrom]

I can confirm it works fine. Feel free to close.