"ref" keyword not allowed for "__runOriginal"

[garrettluskey]

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If you think you found a bug in Harmony please use the following to format:

---

Describe the bug A clear and concise description of what the bug is.

To Reproduce Steps to reproduce the behavior:

internal class ThisIsATest
{
    public void SomeMethod()
    {
        // DO SOMETHING IDK
    }
}

[HarmonyPatch(typeof(ThisIsATest), nameof(ThisIsATest.SomeMethod))]
internal class ThisIsATestPatch
{
    public static bool Prefix()
    {
        // This can be anything
        return true;
    }

    public static void Postfix(ref bool __runOriginal)
    {
        // This crashes
    }
}

Stack Trace

Message: 
HarmonyLib.HarmonyException : Patching exception in method System.Void GameInterface.Services.MobileParties.Patches.ThisIsATest::SomeMethod()
---- System.InvalidProgramException : Common Language Runtime detected an invalid program.

  Stack Trace: 
PatchClassProcessor.ReportException(Exception exception, MethodBase original)
PatchClassProcessor.Patch()
<>c.<PatchAllUncategorized>b__12_1(PatchClassProcessor patchClass)
CollectionExtensions.Do[T](IEnumerable`1 sequence, Action`1 action)
CollectionExtensions.DoIf[T](IEnumerable`1 sequence, Func`2 condition, Action`1 action)
Harmony.PatchAllUncategorized(Assembly assembly)
----- Inner Stack Trace -----
PatchFunctions.UpdateWrapper(MethodBase original, PatchInfo patchInfo)
PatchClassProcessor.ProcessPatchJob(Job job)

Expected behavior Expected no crash or better error to describe what the issue was.

Screenshots / Code If applicable, add material to help explain your problem.

Runtime environment (please complete the following information):

• OS: Wandows
• .NET framework 4.7.2
• Harmony version 2.3.3
  • Name of game or host application: XUnit Test

Additional context Add any other context about the problem here.

Error message isn't that helpful, this issue isn't very serious but could lead some people down an unnecessary rabbit hole.

I'll try to be active on this issue :)

[pardeike]

Have you tried with “ref”? It is of no use since you cannot and should not change the value of the injected value in this case.

[garrettluskey]

This issue is passing ref to the postfix causes the error described above. It appears that adding the "ref" keyword breaks harmony on patching.

[pardeike]

Then don’t add ref. As I said it makes no sense in this case anyway.

[garrettluskey]

Ok, I understand now. What I am suggesting is that the error could be more verbose when passing __runOriginal by reference. If you feel it doesn't add enough value feel free to close this issue

[pardeike]

Seems too esoteric an error to fix. To me it seems obvious that a Boolean you only suppose to read should not use ref at all. Since it’s actually non-trivial to add the error I rather not.