Fix crash when empty blood fluid container ticks in inventory

src/main/java/org/cyclops/evilcraft/EvilCraft.java

@@ -472,6 +472,7 @@ public Class<?>[] getGameTestClasses() {
                 GameTestsEntangledChalice.class,
                 GameTestsItemEternalWater.class,
                 GameTestsItemStacking.class,
+                GameTestsPendant.class,
                 GameTestsRecipes.class,
                 GameTestsSpiritFurnace.class,
                 GameTestsSpiritReanimator.class,

src/main/java/org/cyclops/evilcraft/RegistryEntries.java

@@ -78,6 +78,8 @@ public class RegistryEntries {
     public static final DeferredHolder<Item, Item> ITEM_BOWL_OF_PROMISES_TIER3 = DeferredHolder.create(Registries.ITEM, Identifier.parse("evilcraft:bowl_of_promises_tier3"));
     public static final DeferredHolder<Item, Item> ITEM_BOX_OF_ETERNAL_CLOSURE = DeferredHolder.create(Registries.ITEM, Identifier.parse("evilcraft:box_of_eternal_closure"));
     public static final DeferredHolder<Item, Item> ITEM_BLOOD_EXTRACTOR = DeferredHolder.create(Registries.ITEM, Identifier.parse("evilcraft:blood_extractor"));
+    public static final DeferredHolder<Item, ItemInvigoratingPendant> ITEM_INVIGORATING_PENDANT = DeferredHolder.create(Registries.ITEM, Identifier.parse("evilcraft:invigorating_pendant"));
+    public static final DeferredHolder<Item, ItemPrimedPendant> ITEM_PRIMED_PENDANT = DeferredHolder.create(Registries.ITEM, Identifier.parse("evilcraft:primed_pendant"));
     public static final DeferredHolder<Item, Item> ITEM_BURNING_GEM_STONE = DeferredHolder.create(Registries.ITEM, Identifier.parse("evilcraft:burning_gem_stone"));
     public static final DeferredHolder<Item, Item> ITEM_ENTANGLED_CHALICE = DeferredHolder.create(Registries.ITEM, Identifier.parse("evilcraft:entangled_chalice"));
     public static final DeferredHolder<Item, Item> ITEM_EXALTED_CRAFTER = DeferredHolder.create(Registries.ITEM, Identifier.parse("evilcraft:exalted_crafter"));

src/main/java/org/cyclops/evilcraft/core/item/ItemBloodContainer.java

@@ -164,6 +164,14 @@ public boolean doesSneakBypassUse(ItemStack stack, LevelReader world, BlockPos p
         return true;
     }
 
+    @Override
+    public boolean canDrain(int amount, ItemStack itemStack) {
+        // Avoid IllegalArgumentException when the fluid handler has no fluid (empty resource is not allowed in NeoForge extract calls)
+        FluidStack fluidStack = FluidUtil.getFirstStackContained(itemStack);
+        if (fluidStack.isEmpty()) return false;
+        return super.canDrain(amount, itemStack);
+    }
+
     protected FluidStack drainFromOthers(int amount, ItemStack itemStack, Fluid fluid, Player player, TransactionContext transaction) {
         PlayerExtendedInventoryIterator it = new PlayerExtendedInventoryIterator(player);
         int drained = 0;
@@ -210,7 +218,8 @@ public FluidStack consume(int amount, ItemStack itemStack, @Nullable Player play
         try (var tx = Transaction.openRoot()) {
             ResourceHandler<FluidResource> fluidHandler = itemStack.getCapability(Capabilities.Fluid.ITEM, ItemAccess.forStack(itemStack));
             FluidResource resource = fluidHandler.getResource(0);
-            int drained = fluidHandler.extract(resource, amount, tx);
+            // Avoid IllegalArgumentException when the fluid handler has no fluid (empty resource is not allowed in NeoForge extract calls)
+            int drained = resource.isEmpty() ? 0 : fluidHandler.extract(resource, amount, tx);
             if (drained == amount) return resource.toStack(drained);
             int toDrain = amount - drained;
             FluidStack otherDrained = player == null ? FluidStack.EMPTY : drainFromOthers(toDrain, itemStack, getFluid(), player, tx);

src/main/java/org/cyclops/evilcraft/gametest/GameTestsPendant.java

@@ -0,0 +1,47 @@
+package org.cyclops.evilcraft.gametest;
+
+import net.minecraft.gametest.framework.GameTestHelper;
+import net.minecraft.network.chat.Component;
+import net.minecraft.world.entity.player.Player;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.level.GameType;
+import org.cyclops.cyclopscore.gametest.GameTest;
+import org.cyclops.evilcraft.Reference;
+import org.cyclops.evilcraft.RegistryEntries;
+
+public class GameTestsPendant {
+
+    public static final String TEMPLATE_EMPTY = Reference.MOD_ID + ":empty10";
+
+    /**
+     * Verifies that having an empty invigorating pendant in a player's inventory does not crash.
+     * The crash was caused by DamageIndicatedItemFluidContainer.canDrain calling extract on an empty
+     * fluid resource (minecraft:empty), which throws IllegalArgumentException in NeoForge 21.11.38-beta+.
+     */
+    @GameTest(template = TEMPLATE_EMPTY)
+    public void testInvigoratingPendantInventoryTickEmptyNoCrash(GameTestHelper helper) {
+        Player player = helper.makeMockPlayer(GameType.SURVIVAL);
+        ItemStack pendantStack = new ItemStack(RegistryEntries.ITEM_INVIGORATING_PENDANT);
+
+        // Directly invoke clearBadEffects on an empty pendant - should not throw
+        RegistryEntries.ITEM_INVIGORATING_PENDANT.get().clearBadEffects(pendantStack, player);
+
+        helper.succeed();
+    }
+
+    /**
+     * Verifies that having an empty primed pendant in a player's inventory does not crash.
+     */
+    @GameTest(template = TEMPLATE_EMPTY)
+    public void testPrimedPendantInventoryTickEmptyNoCrash(GameTestHelper helper) {
+        Player player = helper.makeMockPlayer(GameType.SURVIVAL);
+        ItemStack pendantStack = new ItemStack(RegistryEntries.ITEM_PRIMED_PENDANT);
+
+        // canConsume on empty pendant should return false without throwing
+        boolean canConsume = RegistryEntries.ITEM_PRIMED_PENDANT.get().canConsume(1, pendantStack, player);
+        helper.assertFalse(canConsume, Component.literal("Empty pendant should not be consumable"));
+
+        helper.succeed();
+    }
+
+}