ItemUtils#changeItemMeta, #setItem

[TheAbsolutionism]

Description

This PR is to help with shorthand ItemStack changes.
Example: (Before)

for (Object object : getExpr().getArray(event)) {
    ItemStack item = ItemUtils.asItemStack(object);
    if (item == null)
        continue;
    ItemMeta meta = item.getItemMeta();
    consumer.accept(meta);
    item.setItemMeta(meta);
    if (object instanceof Slot slot) {
        slot.setItem(item);
    } else if (object instaceof ItemType itemType) {
        itemType.setItemMeta(meta);
    } else if (object instanceof ItemStack itemStack) {
        itemStack.setItemMeta(meta);
    }
}

(After)

for (Object object : getExpr().getArray(event)) {
    ItemStack item = ItemUtils.asItemStack(object);
    if (item == null)
        continue;
    ItemUtils.setItem(object, ItemUtils.changeItemMeta(item, consumer));
}

Obviously this will more than likely be up for debate but here's hoping.

---

Target Minecraft Versions: any
Requirements: none
Related Issues: none

[APickledWalrus]

Paper has these editMeta methods which might be useful call here if available: https://jd.papermc.io/paper/1.21.4/org/bukkit/inventory/ItemStack.html#editMeta(java.util.function.Consumer)

Though, I'm not sure they are doing anything different internally from what is being done here, so it might be worth looking into that first.

[Fusezion]

As far as I remember they did the exact same thing as he does here, when he was working on it I mentioned in a discord call about it.

[APickledWalrus]

Ah yep, if it's the same then no need to worry about it.