Super calls to default interface methods can be mismapped

[Chocohead]

When a mixin uses one of the target's interface's default methods, any parent class which also implements a method with a matching signature will take the call instead.

In the following situation:

public interface IA {
	String method(int value);
}

public static abstract class A implements IA {
}

public interface IB extends IA {
	default String method(int value) {
		return "I've got " + value;
	}
}

public static class B extends A implements IB {
	public String testCall() {
		return "no mixin";
	}
}

with the following mixin:

@Mixin(B.class)
abstract class BMixin implements IB {
	@Inject(method = "testCall", at = @At("HEAD"))
	private void useInterfaceCall(CallbackInfoReturnable<String> call) {
		call.setReturnValue(IB.super.method(5));
	}
}

You would expect new B().testCall() to return I've got 5, but it instead throws an AbstractMethodError:

java.lang.AbstractMethodError: com.chocohead.example.A.method(I)Ljava/lang/String;
	at com.chocohead.example.B.handler$zzc000$test-mod$addInterfaceCall(B.java:521)
	at com.chocohead.example.B.test(B.java)
	at com.chocohead.example.Test.onInitialize(Test.java)

This is caused by the re-parenting Mixin does to correct super calls in mixins preferring the target's parent interfaces over the target's own...

• MixinTargetContext#transformMethodRef will attempt to re-parent any INVOKESPECIAL call (that isn't to the mixin's parent class) if the mixin's parent class doesn't match the target's, or if any of the target's parent classes have mixins targeting them
• MixinTargetContext#updateStaticBinding sets the Traversal to SUPER
• MixinTargetContext#updateBinding goes looking for a matching method in the hierarchy
• ClassInfo#findInHierarchy looks depth first at the parents and their interfaces before checking its own
• MixinTargetContext#updateBinding sets the call to use the implementer of the found method. For our situation, that's the implementer of IA#method, i.e. A

---

This crash can be caused in a Minecraft context by having an empty mixin targeting FixedColourVertexConsumer whilst Iris is installed before 1.21. This crash is from opening ModMenu on 1.20.4 for example:

java.lang.AbstractMethodError: Method net/minecraft/class_4585.method_22921(II)Lnet/minecraft/class_4588; is abstract
	at net.minecraft.class_4585.method_22921(class_4585.java)
	at net.minecraft.class_287.method_22921(class_287.java:2095)
	at net.minecraft.class_4588.method_22916(class_4588.java:56)
	at net.minecraft.class_382.method_22944(class_382.java:55)
	at net.minecraft.class_327$class_5232.method_27531(class_327.java:282)
	at net.minecraft.class_327.method_27530(class_327.java:299)
	at net.minecraft.class_327.method_1723(class_327.java:147)
	at net.minecraft.class_327.method_22942(class_327.java:84)
	at net.minecraft.class_332.method_51430(class_332.java:289)
	at net.minecraft.class_332.method_35720(class_332.java:285)
	at com.terraformersmc.modmenu.gui.widget.DescriptionListWidget$DescriptionEntry.method_25343(DescriptionListWidget.java:338)
	at net.minecraft.class_350.method_44397(class_350.java:411)
	at net.minecraft.class_350.method_25311(class_350.java:396)
	at com.terraformersmc.modmenu.gui.widget.DescriptionListWidget.method_25311(DescriptionListWidget.java:226)
	at net.minecraft.class_350.method_48579(class_350.java:184)
	at net.minecraft.class_339.method_25394(class_339.java:66)
	at com.terraformersmc.modmenu.gui.ModsScreen.method_25394(ModsScreen.java:301)
	at net.minecraft.class_437.method_47413(class_437.java:110)
	at net.minecraft.class_757.mixinextras$bridge$method_47413$241(class_757.java)
	at net.minecraft.class_757.wrapOperation$znj000$fabric-screen-api-v1$onRenderScreen(class_757.java:2611)
	at net.minecraft.class_757.method_3192(class_757.java:931)
	at net.minecraft.class_310.method_1523(class_310.java:1327)
	at net.minecraft.class_310.method_1514(class_310.java:888)
	at net.minecraft.client.main.Main.main(Main.java:265)
	at net.fabricmc.loader.impl.game.minecraft.MinecraftGameProvider.launch(MinecraftGameProvider.java:470)
	at net.fabricmc.loader.impl.launch.knot.Knot.launch(Knot.java:74)
	at net.fabricmc.loader.impl.launch.knot.KnotClient.main(KnotClient.java:23)

Iris's mixin using BufferVertexConsumer#light is here.

[LlamaLad7]

Will try to fix