Item and Ingredient

When making recipes you can specify items in many ways, the most common is just to use 'namspace:id', like 'minecraft:diamond', however you can also use Item#of and Ingredient#of for advanced additions, such as NBT or count.

Note that Item and Ingredient are not the same! They may work similarly but there are differences. Item can only ever represent a single item type whereas Ingredient can represent multiple item types (and multiple instances of the same item type with different properties such as NBT data). For most cases Ingredient should be preferred over Item.

Item/ItemWrapper

Its Java class name is ItemWrapper but it is bound to Item in JS.

Name	Return Type	Info
of(ItemStackJS in)	ItemStackJS	Returns an ItemStackJS based on what was input. Note that this relies mostly on Rhinos type wrapping to function, see paragraph below about ItemStackJS#of for more info
of(ItemStackJS in, int count)	ItemStackJS	See above. count will override any other count set from the first parameter.
of(ItemStackJS in, CompoundTag tag)	ItemStackJS	See above. ~~nbt~~NBT is merged, with the input ~~nbt~~NBT taking priority over existing ~~nbt.~~NBT.
of(ItemStackJS in, int count, CompoundTag nbt)	ItemStackJS	Combines the functionality of the above two.
withNBT(ItemStackJS in, CompoundTag nbt)	ItemStackJS	Same as the corresponding #of.
withChance(ItemStackJS in, double chance)	ItemStackJS	Same as #of, chance will override currently set chance.
getList()	ListJS	Returns a list of ItemStackJS, one per registered item.
getTypeList()	ListJS	Returns a list of String, one per registered item.
getEmpty()	ItemStackJS	Returns ItemSTackJS.EMPTY
clearListCache()	void	Clears the caches used for #getList and #getTypeList
fireworks(Map<String, Object> properties)	FireworkJS	Returns a FireworkJS based on the input map of propeties. See FireworkJS#of on the FireworkJS page for more information <TODO: Make and link FireworkJS page>
getItem(ResourceLocation id)	Item	Returns the instance of the Item class associated with the item id passed in.
@Nullable findGroup(String id)	CreativeModTab	Returns the Creative tab associated with the id passed in, returns null if none found.
exists(ResourceLocation id)	boolean	Returns if the item id passed in exists or not.
isItem(@Nullable Object o)	boolean	Just does an instanceof ItemStackJS check on the object passed in.

Item#of relies on Rhinos type wrapping to function, which calls ItemStackJS#of. This tries its best to turn the input into an ItemStackJS. If no match is found ItemStackJS.EMPTY is returned. Valid inputs:

null/ItemStack.EMPTY/Items.EMPTY/ItemStackJS.EMPTY - will return ItemStackJS.EMPTY
ItemStackJS - will return the same object passed in.
FluidStackJS - will return a new DummyFluidItemStackJS
IngredientJS - will return the first item in the Ingredient
ItemStack - will return a new ItemStackJS wrapping the ItemStack passed in
ResourceLocation - will lookup this ResourceLocation in the item registry and return it if found. If not found will return ItemStackJS.EMPTY, and throw an error if RecipeJS.itemErrors is true
ItemLike - will return a new ItemStackJS of the input
JsonObject - will return an item based on properties in the Json. item will be used as the item id, or tag if item does not exist. count, chance and nbt all set their respective properties
RegEx - will return a new ItemStackJS of the first item id that matches this regex.
String (CharSequence) - will parse it and return a new ItemStackJS based on the input item id. Prefix with nx to change the count (where n is any number between 1 and 64). Put # before the item id to parse it as a tag instead. Put @ before the item id to parse it as a modid instead. Prefix with % to parse it as a creative menu tab group. Surround in / to parse as a RegEx. NOTE: will only be the first item in any of the groups mentioned above!
Map/JS Object - uses the same rules as a JsonObject.

Ingredient/IngredientWrapper

Its Java class name is IngredientWrapper but it is bound to Ingredient in JS. All static methods.

Name	Return Type	Info
getNone()	IngredientJS	Returns ItemStack.EMPTY
getAll()	IngredientJS	Returns an IngredientJS of every single item in game. All of them.
of(Object object)	IngredientJS	Works exactly the same as Item#of except it recognises Ingredient and forge json ingredient syntax.
of(Object object, int count)	IngredientJS	Same as above. The count passed in will override any from the first parameter.
custom(Predicate<ItemStackJS> predicate)	IngredientJS	Takes the arrow function or anonymous function passed in and makes an IngredientJS with that as ~~#test.~~IngredientJS#test. Return true from the function if the ItemStackJS passed should match as an ingredient.
custom(IngredientJS in, Predicate<ItemStackJS> predicate)	IngredientJS	Same as above except it must match the IngredientJS passed in as the first parameter before the custom function is called.
customNBT(IngredientJS in, Predicate<CompoundTag> predicate)	IngredientJS	Same as above except the Predicate is passed the items ~~nbt~~NBT instead of the full ItemStackJS. Useful for advanced NBT matching.
matchAny(Object objects)	IngredientJS	Adds the passed in object to an ingredient. If it is a list then it adds all items in the list. All objects are passed through #of before adding.
registerCustomIngredientAction(String id, CustomIngredientActionCallback callback)	void	Registers a custom ingredient action. See the recipe page for more information.
isIngredient(@Nullable Object o)	boolean	Just does an instanceof IngredientJS check on the object passed in.

Remember that Item and Ingredient are not equivalent!

Examples

<TODO: examples>

ItemStackJS

A wrapper class for vanilla's ItemStack. All methods listed here are instance methods, all useful static methods are wrapped in ItemWrapper. Implements IngredientJS and overrides most of its default methods.

Name	Return Type	Info
~~EMPTY~~getItem()	Item	Returns the instance of the Item class associated with this ItemStackJS.
getItemStack()	ItemStack	Returns the vanilla ItemStack that this wraps.
getId()	String	Returns the item id associated with this ItemStackJS in the form mod_name:item_name
getTags()	Colletion<ResourceLocation>	Returns all item tags the item has. (NOT NBT tags).
hasTag(ResourceLocation tag)	boolean	Returns if the item has the input tag or not.
copy()	ItemStackJS	~~The~~Returns a copy of this ItemStackJS.
setCount(int count)	void	Sets the count on this ItemStackJS.
getCount()	int	Gets the count.
withCount()	ItemStackJS	Returns a copy of this ItemStackJS with a different count.
isEmpty()	boolean	Returns if this is an empty ~~instance~~item or not.
isInvalidRecipeIngredient()	boolean	Returns if this is a valid recipe ingredient.
isBlock()	boolean	Returns if this item is a BlockItem, that is it can be placed and form a block.
@Nullable getNbt()	CompoundTag	Gets this items NBT data.
setNbt(@Nullable CompoundTag tag)	void	Sets this items NBT data
hasNBT()	boolean	Returns if this item has NBT data.
getNbtString()	String	Returns this items NBT data as a string. If you want to display it to the player see Text#prettyPrintNbt.
removeNBT()	ItemStackJS	Returns a copy with no NBT data.
withNBT(CompoundTag nbt)	ItemStackJS	Returns a copy with the specified NBT data. Any tags from the original NBT are kept if not overwritten by the NBT passed in.
hasChance()	boolean	Returns if the ItemStackJS has a chance.
removeChance()	void	Removes the chance from this ItemStackJS.
setChance(double c)	void	Sets the chance for this ItemStackJS.
getChance()	double	Returns the chance.
withChance(double c)	ItemStackJS	Returns a copy with the chance passed in, unless the chance passed in is the same as the current chance, in which case it returns this.
getName()	Components	Returns this items name. Probably a Translateable Component unless its been overridden by something else (ie method below).
withName(@Nullable Component displayName)	ItemStackJS	Returns a copy with a different display name set.
toString()	String	Returns a string representing this ItemStackJS. The same method used for the `/kubejs hand` command.
test(ItemStackJS other)	boolean	Returns if this ItemStackJS equals another one. Tests for item type and NBT data.
testVanilla(ItemStack other)	boolean	Returns if this ItemStackJS equals the passed in ItemStack. Tests for item type and NBT data.
testVanillaItem(Item item)	boolean	Returns if the Item passed in is the same as this ItemStackJS's Item. Basically checks they are the same item type.
getStacks()	Set<ItemStackJS>	Returns this ItemStackJS as the only entry in a Set.
getVanillaItems()	Set<Item>	Returns this ItemStackJS associated Item as the only entry in a Set.
getFirst()	ItemStackJS	Retuns a copy of ~~ItemStack.EMPTY~~this ItemStackJS
hashCode()	int	Returns a hash code of the Item and NBT data.
equals(Object o)	boolean	Returns if this is equal to the input object.
strongEquals(Object o)	boolean	Returns if this is equal to the input object. Checks count as well.
getEnchantments()	MapJS	Returns a MapJS of this itemStackJS enchament id's to their level.
hasEnchantment(Enchantment enchantment, int level)	boolean	Returns if this ItemStackJS is enchanted with a minimum of the passed in enchantment level.
enchant(MapJS enchantments)	ItemStackJS	Enchants a copy of this ItemStackJS with the MapJS passed in (it should be a map of enchantment ids to levels), then returns the copy.
enchant(Enchantment enchantment, int level)	ItemStackJS	Enchants a copy of this item with the passed in Enchantment at the specified level, then returns the copy.
getMod()	String	Returns the mod id of the mod this item is from.
ignoreNBT()	IngredientJS	Returns a new IgnoreNBTIngredientJS of this item.
weakNBT()	IngredientJS	Returns a new WeakNBTIngredientJS of this item.
areItemsEqual(ItemStackJS other)	boolean	Returns if this item type is equal to the item type of the passed in ItemStackJS
areItemsEqual(ItemStack other)	boolean	Returns if this item type is equal to the item type of the passed in ItemStack
isNBTEqual(ItemStackJS other)	boolean	Returns if the NBT of this ItemStackJS is equal to the NBT of the ItemStackJS passed in.
isNBTEqual(ItemStack other)	boolean	Returns if the NBT of this ItemStackJS is equal to the NBT of the ItemStack passed in.
getHarvestSpeed(@Nullable BlockContainerJS block)	float	Returns the mining speed of this ItemStackJS if used to mine the passed in BlockContainerJS
getHarvestSpeed()	float	Returns this items default mining speed
toJson() toResultJson() toRawResultJson()	JsonElement	Returns a Json representation of this ItemStackJS. They all appear to work almost identically.
toNBT()	CompoundTag	Returns an NBT representation of this ItemStackJS, the same sort that vanilla uses to store items in blocks.
onChanged(@Nullable Tag o)	void	Sets the items NBT data to the tag passed in, only if it is a CompoundTag or null.
getItemGroup()	String	Returns the name of the creative tab this item belongs in. An empty string if it does not exist in the creative tabs (like a jigsaw block).
getItemIds()	Set<String>	Returns a set with this items id as the only entry.
getFluidStack()	FluidStackJS	Returns null, by default. Overriden by some superclasses to return the FluidStackJS that this item represents.
getTypeData()	CompoundTag	Unknown purpose.

<TODO: Examples>

IngredientJS

~~IngredientJS is just a functional interface with a bunch of extra static methods. 'nuff said.~~