Fix SidedInvWrapper not accounting for vanilla stacking special cases in brewing stands and furnaces (#9189)

src/main/java/net/minecraftforge/items/wrapper/SidedInvWrapper.java

@@ -8,18 +8,30 @@ package net.minecraftforge.items.wrapper;
 import net.minecraft.world.WorldlyContainer;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.core.Direction;
+import net.minecraft.world.item.Items;
+import net.minecraft.world.level.block.entity.AbstractFurnaceBlockEntity;
+import net.minecraft.world.level.block.entity.BrewingStandBlockEntity;
 import net.minecraftforge.common.util.LazyOptional;
 import net.minecraftforge.items.IItemHandlerModifiable;
 import net.minecraftforge.items.ItemHandlerHelper;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.util.function.IntUnaryOperator;
+
 public class SidedInvWrapper implements IItemHandlerModifiable
 {
     protected final WorldlyContainer inv;
     @Nullable
     protected final Direction side;
 
+    private final IntUnaryOperator slotLimit;
+    private final InsertLimit newStackInsertLimit;
+    private interface InsertLimit
+    {
+        int limitInsert(int wrapperSlot, int invSlot, ItemStack stack);
+    }
+
     @SuppressWarnings("unchecked")
     public static LazyOptional<IItemHandlerModifiable>[] create(WorldlyContainer inv, Direction... sides) {
         LazyOptional<IItemHandlerModifiable>[] ret = new LazyOptional[sides.length];
@@ -34,6 +46,20 @@ public class SidedInvWrapper implements IItemHandlerModifiable
     {
         this.inv = inv;
         this.side = side;
+
+        // A few special cases to account for canPlaceItem implementations attempting to limit specific inputs to 1,
+        // by returning false if there's already a contained item. This doesn't work with modded inserted sizes > 1.
+        // - Limit buckets to 1 in furnace fuel inputs.
+        // - Limit brewing stand "bottle" inputs to 1.
+        // Done using lambdas to avoid the overhead of instanceof checks in hot code.
+        if (inv instanceof BrewingStandBlockEntity)
+            this.slotLimit = wrapperSlot -> getSlot(inv, wrapperSlot, side) < 3 ? 1 : inv.getMaxStackSize();
+        else
+            this.slotLimit = wrapperSlot -> inv.getMaxStackSize();
+        if (inv instanceof AbstractFurnaceBlockEntity)
+            this.newStackInsertLimit = (wrapperSlot, invSlot, stack) -> invSlot == 1 && stack.is(Items.BUCKET) ? 1 : Math.min(stack.getMaxStackSize(), getSlotLimit(wrapperSlot));
+        else
+            this.newStackInsertLimit = (wrapperSlot, invSlot, stack) -> Math.min(stack.getMaxStackSize(), getSlotLimit(wrapperSlot));
     }
 
     public static int getSlot(WorldlyContainer inv, int slot, @Nullable Direction side)
@@ -141,7 +167,8 @@ public class SidedInvWrapper implements IItemHandlerModifiable
             if (!inv.canPlaceItemThroughFace(slot1, stack, side) || !inv.canPlaceItem(slot1, stack))
                 return stack;
 
-            m = Math.min(stack.getMaxStackSize(), getSlotLimit(slot));
+            m = newStackInsertLimit.limitInsert(slot, slot1, stack);
+
             if (m < stack.getCount())
             {
                 // copy the stack to not modify the original one
@@ -226,7 +253,7 @@ public class SidedInvWrapper implements IItemHandlerModifiable
     @Override
     public int getSlotLimit(int slot)
     {
-        return inv.getMaxStackSize();
+        return slotLimit.applyAsInt(slot);
     }
 
     @Override