From 75c9a5e3d8bcac4da05f72fc30f171ea5180010d Mon Sep 17 00:00:00 2001
From: Andrii Chebukin <XperiAndri@Outlook.com>
Date: Mon, 30 Jun 2025 01:36:27 +0400
Subject: [PATCH] refactor(config): remove `Newtonsoft.Json` in favor of
 `System.Text.Json`

---
 CHANGELOG.md                                  |  1 +
 Directory.Packages.props                      |  2 +-
 .../FSharpLint.Console.fsproj                 |  1 -
 .../Application/Configuration.fs              | 47 +++++--------------
 src/FSharpLint.Core/FSharpLint.Core.fsproj    |  1 -
 5 files changed, 14 insertions(+), 38 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 92d83cac6..bcddf844a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Remove `NoPartialFunctions` compiler workaround (#698) [@webwarrior-ws]
 - Add `SLNX` and `SLNF` format support and migrate to SLNX solution #723 [@xperiandri]\
   Remove `Ionide.ProjInfo.Sln` NuGet package dependency
+- Remove `Newtonsoft.Json` NuGet dependency #725 [@xperiandri]
 
 ## [0.24.2] - 2024-02-29
 
diff --git a/Directory.Packages.props b/Directory.Packages.props
index 76426fc2c..9a5a76174 100644
--- a/Directory.Packages.props
+++ b/Directory.Packages.props
@@ -21,9 +21,9 @@
     <PackageVersion Include="Microsoft.Build.Tasks.Core" Version="17.14.8" />
     <PackageVersion Include="Microsoft.Build.Utilities.Core" Version="17.14.8" />
     <PackageVersion Include="Microsoft.SourceLink.GitHub" Version="8.0.0" />
-    <PackageVersion Include="Newtonsoft.Json" Version="13.0.3" />
     <PackageVersion Include="NUnit" Version="3.14.0" />
     <PackageVersion Include="NUnit3TestAdapter" Version="5.0.0" />
     <PackageVersion Include="System.Reactive" Version="6.0.1" />
+    <PackageVersion Include="System.Text.Json" Version="9.0.0" />
   </ItemGroup>
 </Project>
\ No newline at end of file
diff --git a/src/FSharpLint.Console/FSharpLint.Console.fsproj b/src/FSharpLint.Console/FSharpLint.Console.fsproj
index 5be5cdf16..a6f2c866d 100644
--- a/src/FSharpLint.Console/FSharpLint.Console.fsproj
+++ b/src/FSharpLint.Console/FSharpLint.Console.fsproj
@@ -29,7 +29,6 @@
   <ItemGroup>
     <PackageReference Include="Argu" />
     <PackageReference Include="FSharp.Core" />
-    <PackageReference Include="Newtonsoft.Json" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/src/FSharpLint.Core/Application/Configuration.fs b/src/FSharpLint.Core/Application/Configuration.fs
index 52d7098c3..e28b1b278 100644
--- a/src/FSharpLint.Core/Application/Configuration.fs
+++ b/src/FSharpLint.Core/Application/Configuration.fs
@@ -4,7 +4,8 @@ module FSharpLint.Framework.Configuration
 open System
 open System.IO
 open System.Reflection
-open Newtonsoft.Json
+open System.Text.Json
+open System.Text.Json.Serialization
 open FSharpLint.Framework
 open FSharpLint.Framework.Rules
 open FSharpLint.Framework.HintParser
@@ -15,40 +16,16 @@ let SettingsFileName = "fsharplint.json"
 
 exception ConfigurationException of string
 
-module FSharpJsonConverter =
-    open Microsoft.FSharp.Reflection
-
-    type OptionConverter() =
-        inherit JsonConverter()
-
-        override x.CanConvert(t) =
-            t.IsGenericType && t.GetGenericTypeDefinition() = typedefof<_ option>
-
-        override x.WriteJson(writer, value, serializer) =
-            let value =
-                if isNull value then null
-                else
-                    let _,fields = FSharpValue.GetUnionFields(value, value.GetType())
-                    fields.[0]
-            serializer.Serialize(writer, value)
-
-        override x.ReadJson(reader, t, _, serializer) =
-            let innerType = t.GetGenericArguments().[0]
-            let innerType =
-                if innerType.IsValueType then (typedefof<Nullable<_>>).MakeGenericType([|innerType|])
-                else innerType
-            let value = serializer.Deserialize(reader, innerType)
-            let cases = FSharpType.GetUnionCases(t)
-            if isNull value then FSharpValue.MakeUnion(cases.[0], [||])
-            else FSharpValue.MakeUnion(cases.[1], [|value|])
-
-    let private converters =
-        [|
-            OptionConverter() :> JsonConverter
-        |]
+module internal FSharpJsonConverter =
 
-    let serializerSettings =
-        JsonSerializerSettings(NullValueHandling = NullValueHandling.Ignore, Converters = converters)
+    let jsonOptions =
+        let options =
+            JsonSerializerOptions(
+                PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
+                DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull
+            )
+        options.Converters.Add(JsonStringEnumConverter())
+        options
 
 module IgnoreFiles =
 
@@ -582,7 +559,7 @@ with
 /// Tries to parse the provided config text.
 let parseConfig (configText:string) =
     try
-        JsonConvert.DeserializeObject<Configuration>(configText, FSharpJsonConverter.serializerSettings)
+        JsonSerializer.Deserialize<Configuration>(configText, FSharpJsonConverter.jsonOptions)
     with
     | ex -> raise <| ConfigurationException $"Couldn't parse config, error=%s{ex.Message}"
 
diff --git a/src/FSharpLint.Core/FSharpLint.Core.fsproj b/src/FSharpLint.Core/FSharpLint.Core.fsproj
index f6dac62ba..c73bdac00 100644
--- a/src/FSharpLint.Core/FSharpLint.Core.fsproj
+++ b/src/FSharpLint.Core/FSharpLint.Core.fsproj
@@ -151,7 +151,6 @@
     <PackageReference Include="Microsoft.Build.Tasks.Core" ExcludeAssets="runtime" />
     <PackageReference Include="Microsoft.Build.Utilities.Core" ExcludeAssets="runtime" />
     <PackageReference Include="Microsoft.SourceLink.GitHub" PrivateAssets="all" />
-    <PackageReference Include="Newtonsoft.Json" />
   </ItemGroup>
 
 </Project>