TypeLoadException when patching a method in a class, which inherits a class that has a generic argument of type enum

[btastic]

Describe the bug I want to patch a method which is residing in a class, that inherits from a class which has a generic argument of 'T' where 'T' is enum.

To Reproduce I compiled a little package with a simple repro.

You can download the zip file here: https://we.tl/t-yfbtmiVmA5

The packaged game is prepatched with MelonLoader 0.6.1

Steps to reproduce the behavior:

1. The original method and its signature and class

using System;
using UnityEngine;

public enum GameScreen
{
    Title = 0,
    Game = 1,
}

public class MyGameScreen : GameScreen<GameScreen>
{
    private int _something = 0;

    public void SetSomething(int i)
    {
        _something = i;
    }

    void Start()
    {
    }

    void Update()
    {
    }
}

public class GameScreen<T> : MonoBehaviour where T : Enum
{

}

3. The patch code

   
   [HarmonyPatch(typeof(MyGameScreen), "SetSomething", new Type[] { typeof(int) })]
   public static class Patch
   {
   private static void Prefix()
   {
       // The code inside this method will run before 'PrivateMethod' is executed
   }
   
   private static void Postfix()
   {
       // The code inside this method will run after 'PrivateMethod' has executed
   }
   }

public class Mod : MelonMod {

}

Errors:

[14:48:45.178] [PWS_Tool_Mod] System.TypeLoadException: GenericArguments[0], 'Il2Cpp.GameScreen', on 'Il2Cpp.GameScreen1[T]' violates the constraint of type parameter 'T'. at System.Reflection.CustomAttribute._CreateCaObject(RuntimeModule pModule, RuntimeType type, IRuntimeMethodInfo pCtor, Byte** ppBlob, Byte* pEndBlob, Int32* pcNamedArgs) at System.Reflection.CustomAttribute.CreateCaObject(RuntimeModule module, RuntimeType type, IRuntimeMethodInfo ctor, IntPtr& blob, IntPtr blobEnd, Int32& namedArgs) at System.Reflection.CustomAttribute.AddCustomAttributes(ListBuilder1& attributes, RuntimeModule decoratedModule, Int32 decoratedMetadataToken, RuntimeType attributeFilterType, Boolean mustBeInheritable, ListBuilder1 derivedAttributes) at System.Reflection.CustomAttribute.GetCustomAttributes(RuntimeType type, RuntimeType caType, Boolean inherit) at System.RuntimeType.GetCustomAttributes(Boolean inherit) at HarmonyLib.HarmonyMethodExtensions.GetFromType(Type type) at HarmonyLib.PatchClassProcessor..ctor(Harmony instance, Type type, Boolean allowUnannotatedType) at HarmonyLib.PatchClassProcessor..ctor(Harmony instance, Type type) at HarmonyLib.Harmony.CreateClassProcessor(Type type) at HarmonyLib.Harmony.<PatchAll>b__11_0(Type type) at HarmonyLib.CollectionExtensions.Do[T](IEnumerable1 sequence, Action1 action) at HarmonyLib.Harmony.PatchAll(Assembly assembly) at MelonLoader.MelonMod.HarmonyInit() in D:\a\MelonLoader\MelonLoader\MelonLoader\Melons\MelonMod.cs:line 40 at MelonLoader.MelonEvent.<>c.<Invoke>b__1_0(LemonAction x) in D:\a\MelonLoader\MelonLoader\MelonLoader\Melons\Events\MelonEvent.cs:line 174 at MelonLoader.MelonEventBase1.Invoke(Action`1 delegateInvoker) in D:\a\MelonLoader\MelonLoader\MelonLoader\Melons\Events\MelonEvent.cs:line 143

**Expected behavior**
It should not error..?

**Screenshots / Code**
Not much to say here. I originally intend to patch a game which uses the same unity version, the same code structure etc.

**Runtime environment (please complete the following information):**
 - OS: **Windows 11**
 - .NET version: **.NET Standard**
 - Harmony version: **2.10.1.0**
- Name of game or host application: **doesn't matter, I included a custom made sample which reproduces the same error as in the game**

**Additional context**
Add any other context about the problem here.

[pardeike]

Not my project. You want to direct your question to the author of HarmonyX

[btastic]

I raised the issue there, in case someone stumbles up on this: https://github.com/BepInEx/HarmonyX/issues/73