EpicCookie.java

package hephaestus.dev.automotion.mixin.item;

import net.minecraft.item.Item;
import net.minecraft.item.Items;
import net.minecraft.util.Rarity;
import org.spongepowered.asm.mixin.Mixin;
import org.spongepowered.asm.mixin.injection.At;
import org.spongepowered.asm.mixin.injection.ModifyArg;
import org.spongepowered.asm.mixin.injection.Slice;

@Mixin(Items.class)
public class EpicCookie {
  @ModifyArg(method = "<clinit>",
      slice = @Slice(
          from = @At(
              // We're going to be looking at everything after the constant with the value 'cookie'
              value = "CONSTANT",
              args = "stringValue=cookie"
          )
      ),
      at = @At(
          // We want to modify the args when the constructor for Item is invoked
          value = "INVOKE",
          // The descriptor for the constructor
          target = "Lnet/minecraft/item/Item;<init>(Lnet/minecraft/item/Item$Settings;)V",
          // We only want to modify the args for the first constructor
          ordinal = 0
      )
  )
  private static Item.Settings adjustItemSettings(Item.Settings settings) {
    return settings.rarity(Rarity.EPIC);
  }
}