git.delta.rocks / unique-network / refs/commits / b08cb26894de

difftreelog

Merge pull request #355 from UniqueNetwork/feature/nft-children

Yaroslav Bolyukin2022-05-30parents: #764dfd5 #8cbbfc6.patch.diff
in: master
Structure children map

12 files changed

modifiedpallets/common/src/lib.rsdiffbeforeafterboth
--- a/pallets/common/src/lib.rs
+++ b/pallets/common/src/lib.rs
@@ -353,6 +353,8 @@
 		MustBeTokenOwner,
 		/// No permission to perform action
 		NoPermission,
+		/// Destroying only empty collections is allowed
+		CantDestroyNotEmptyCollection,
 		/// Collection is not in mint mode.
 		PublicMintingNotAllowed,
 		/// Address is not in allow list.
@@ -1268,6 +1270,18 @@
 		budget: &dyn Budget,
 	) -> DispatchResult;
 
+	fn nest(
+		&self,
+		under: TokenId,
+		to_nest: (CollectionId, TokenId)
+	);
+
+	fn unnest(
+		&self,
+		under: TokenId,
+		to_nest: (CollectionId, TokenId)
+	);
+
 	fn account_tokens(&self, account: T::CrossAccountId) -> Vec<TokenId>;
 	fn collection_tokens(&self) -> Vec<TokenId>;
 	fn token_exists(&self, token: TokenId) -> bool;
modifiedpallets/fungible/src/common.rsdiffbeforeafterboth
--- a/pallets/fungible/src/common.rs
+++ b/pallets/fungible/src/common.rs
@@ -298,6 +298,18 @@
 		fail!(<Error<T>>::FungibleDisallowsNesting)
 	}
 
+	fn nest(
+		&self,
+		_under: TokenId,
+		_to_nest: (CollectionId, TokenId)
+	) {}
+
+	fn unnest(
+		&self,
+		_under: TokenId,
+		_to_nest: (CollectionId, TokenId)
+	) {}
+
 	fn collection_tokens(&self) -> Vec<TokenId> {
 		vec![TokenId::default()]
 	}
modifiedpallets/fungible/src/lib.rsdiffbeforeafterboth
before · pallets/fungible/src/lib.rs
1// Copyright 2019-2022 Unique Network (Gibraltar) Ltd.2// This file is part of Unique Network.34// Unique Network is free software: you can redistribute it and/or modify5// it under the terms of the GNU General Public License as published by6// the Free Software Foundation, either version 3 of the License, or7// (at your option) any later version.89// Unique Network is distributed in the hope that it will be useful,10// but WITHOUT ANY WARRANTY; without even the implied warranty of11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the12// GNU General Public License for more details.1314// You should have received a copy of the GNU General Public License15// along with Unique Network. If not, see <http://www.gnu.org/licenses/>.1617#![cfg_attr(not(feature = "std"), no_std)]1819use core::ops::Deref;20use evm_coder::ToLog;21use frame_support::{ensure};22use pallet_evm::account::CrossAccountId;23use up_data_structs::{24	AccessMode, CollectionId, TokenId, CreateCollectionData, mapping::TokenAddressMapping,25	budget::Budget,26};27use pallet_common::{28	Error as CommonError, Event as CommonEvent, Pallet as PalletCommon, CollectionHandle,29	dispatch::CollectionDispatch, eth::collection_id_to_address,30};31use pallet_evm::Pallet as PalletEvm;32use pallet_structure::Pallet as PalletStructure;33use pallet_evm_coder_substrate::WithRecorder;34use sp_core::H160;35use sp_runtime::{ArithmeticError, DispatchError, DispatchResult};36use sp_std::{collections::btree_map::BTreeMap};3738pub use pallet::*;3940use crate::erc::ERC20Events;41#[cfg(feature = "runtime-benchmarks")]42pub mod benchmarking;43pub mod common;44pub mod erc;45pub mod weights;4647pub type CreateItemData<T> = (<T as pallet_evm::account::Config>::CrossAccountId, u128);48pub(crate) type SelfWeightOf<T> = <T as Config>::WeightInfo;4950#[frame_support::pallet]51pub mod pallet {52	use frame_support::{Blake2_128, Blake2_128Concat, Twox64Concat, pallet_prelude::*, storage::Key};53	use up_data_structs::CollectionId;54	use super::weights::WeightInfo;5556	#[pallet::error]57	pub enum Error<T> {58		/// Not Fungible item data used to mint in Fungible collection.59		NotFungibleDataUsedToMintFungibleCollectionToken,60		/// Not default id passed as TokenId argument61		FungibleItemsHaveNoId,62		/// Tried to set data for fungible item63		FungibleItemsDontHaveData,64		/// Fungible token does not support nested65		FungibleDisallowsNesting,66		/// Setting item properties is not allowed67		SettingPropertiesNotAllowed,68	}6970	#[pallet::config]71	pub trait Config:72		frame_system::Config + pallet_common::Config + pallet_structure::Config + pallet_evm::Config73	{74		type WeightInfo: WeightInfo;75	}7677	#[pallet::pallet]78	#[pallet::generate_store(pub(super) trait Store)]79	pub struct Pallet<T>(_);8081	#[pallet::storage]82	pub type TotalSupply<T: Config> =83		StorageMap<Hasher = Twox64Concat, Key = CollectionId, Value = u128, QueryKind = ValueQuery>;8485	#[pallet::storage]86	pub type Balance<T: Config> = StorageNMap<87		Key = (88			Key<Twox64Concat, CollectionId>,89			Key<Blake2_128Concat, T::CrossAccountId>,90		),91		Value = u128,92		QueryKind = ValueQuery,93	>;9495	#[pallet::storage]96	pub type Allowance<T: Config> = StorageNMap<97		Key = (98			Key<Twox64Concat, CollectionId>,99			Key<Blake2_128, T::CrossAccountId>,100			Key<Blake2_128Concat, T::CrossAccountId>,101		),102		Value = u128,103		QueryKind = ValueQuery,104	>;105}106107pub struct FungibleHandle<T: Config>(pallet_common::CollectionHandle<T>);108impl<T: Config> FungibleHandle<T> {109	pub fn cast(inner: pallet_common::CollectionHandle<T>) -> Self {110		Self(inner)111	}112	pub fn into_inner(self) -> pallet_common::CollectionHandle<T> {113		self.0114	}115	pub fn common_mut(&mut self) -> &mut pallet_common::CollectionHandle<T> {116		&mut self.0117	}118}119impl<T: Config> WithRecorder<T> for FungibleHandle<T> {120	fn recorder(&self) -> &pallet_evm_coder_substrate::SubstrateRecorder<T> {121		self.0.recorder()122	}123	fn into_recorder(self) -> pallet_evm_coder_substrate::SubstrateRecorder<T> {124		self.0.into_recorder()125	}126}127impl<T: Config> Deref for FungibleHandle<T> {128	type Target = pallet_common::CollectionHandle<T>;129130	fn deref(&self) -> &Self::Target {131		&self.0132	}133}134135impl<T: Config> Pallet<T> {136	pub fn init_collection(137		owner: T::AccountId,138		data: CreateCollectionData<T::AccountId>,139	) -> Result<CollectionId, DispatchError> {140		<PalletCommon<T>>::init_collection(owner, data)141	}142	pub fn destroy_collection(143		collection: FungibleHandle<T>,144		sender: &T::CrossAccountId,145	) -> DispatchResult {146		let id = collection.id;147148		// =========149150		PalletCommon::destroy_collection(collection.0, sender)?;151152		<TotalSupply<T>>::remove(id);153		<Balance<T>>::remove_prefix((id,), None);154		<Allowance<T>>::remove_prefix((id,), None);155		Ok(())156	}157158	pub fn burn(159		collection: &FungibleHandle<T>,160		owner: &T::CrossAccountId,161		amount: u128,162	) -> DispatchResult {163		let total_supply = <TotalSupply<T>>::get(collection.id)164			.checked_sub(amount)165			.ok_or(<CommonError<T>>::TokenValueTooLow)?;166167		let balance = <Balance<T>>::get((collection.id, owner))168			.checked_sub(amount)169			.ok_or(<CommonError<T>>::TokenValueTooLow)?;170171		if collection.permissions.access() == AccessMode::AllowList {172			collection.check_allowlist(owner)?;173		}174175		// =========176177		if balance == 0 {178			<Balance<T>>::remove((collection.id, owner));179		} else {180			<Balance<T>>::insert((collection.id, owner), balance);181		}182		<TotalSupply<T>>::insert(collection.id, total_supply);183184		<PalletEvm<T>>::deposit_log(185			ERC20Events::Transfer {186				from: *owner.as_eth(),187				to: H160::default(),188				value: amount.into(),189			}190			.to_log(collection_id_to_address(collection.id)),191		);192		<PalletCommon<T>>::deposit_event(CommonEvent::ItemDestroyed(193			collection.id,194			TokenId::default(),195			owner.clone(),196			amount,197		));198		Ok(())199	}200201	pub fn transfer(202		collection: &FungibleHandle<T>,203		from: &T::CrossAccountId,204		to: &T::CrossAccountId,205		amount: u128,206		nesting_budget: &dyn Budget,207	) -> DispatchResult {208		ensure!(209			collection.limits.transfers_enabled(),210			<CommonError<T>>::TransferNotAllowed,211		);212213		if collection.permissions.access() == AccessMode::AllowList {214			collection.check_allowlist(from)?;215			collection.check_allowlist(to)?;216		}217		<PalletCommon<T>>::ensure_correct_receiver(to)?;218219		let balance_from = <Balance<T>>::get((collection.id, from))220			.checked_sub(amount)221			.ok_or(<CommonError<T>>::TokenValueTooLow)?;222		let balance_to = if from != to {223			Some(224				<Balance<T>>::get((collection.id, to))225					.checked_add(amount)226					.ok_or(ArithmeticError::Overflow)?,227			)228		} else {229			None230		};231232		if let Some(target) = T::CrossTokenAddressMapping::address_to_token(to) {233			let handle = <CollectionHandle<T>>::try_get(target.0)?;234			let dispatch = T::CollectionDispatch::dispatch(handle);235			let dispatch = dispatch.as_dyn();236237			dispatch.check_nesting(238				from.clone(),239				(collection.id, TokenId::default()),240				target.1,241				nesting_budget,242			)?;243		}244245		// =========246247		if let Some(balance_to) = balance_to {248			// from != to249			if balance_from == 0 {250				<Balance<T>>::remove((collection.id, from));251			} else {252				<Balance<T>>::insert((collection.id, from), balance_from);253			}254			<Balance<T>>::insert((collection.id, to), balance_to);255		}256257		<PalletEvm<T>>::deposit_log(258			ERC20Events::Transfer {259				from: *from.as_eth(),260				to: *to.as_eth(),261				value: amount.into(),262			}263			.to_log(collection_id_to_address(collection.id)),264		);265		<PalletCommon<T>>::deposit_event(CommonEvent::Transfer(266			collection.id,267			TokenId::default(),268			from.clone(),269			to.clone(),270			amount,271		));272		Ok(())273	}274275	pub fn create_multiple_items(276		collection: &FungibleHandle<T>,277		sender: &T::CrossAccountId,278		data: BTreeMap<T::CrossAccountId, u128>,279		nesting_budget: &dyn Budget,280	) -> DispatchResult {281		if !collection.is_owner_or_admin(sender) {282			ensure!(283				collection.permissions.mint_mode(),284				<CommonError<T>>::PublicMintingNotAllowed285			);286			collection.check_allowlist(sender)?;287288			for (owner, _) in data.iter() {289				collection.check_allowlist(owner)?;290			}291		}292293		let total_supply = data294			.iter()295			.map(|(_, v)| *v)296			.try_fold(<TotalSupply<T>>::get(collection.id), |acc, v| {297				acc.checked_add(v)298			})299			.ok_or(ArithmeticError::Overflow)?;300301		let mut balances = data;302		for (k, v) in balances.iter_mut() {303			*v = <Balance<T>>::get((collection.id, &k))304				.checked_add(*v)305				.ok_or(ArithmeticError::Overflow)?;306		}307308		for (to, _) in balances.iter() {309			if let Some(target) = T::CrossTokenAddressMapping::address_to_token(to) {310				let handle = <CollectionHandle<T>>::try_get(target.0)?;311				let dispatch = T::CollectionDispatch::dispatch(handle);312				let dispatch = dispatch.as_dyn();313314				dispatch.check_nesting(315					sender.clone(),316					(collection.id, TokenId::default()),317					target.1,318					nesting_budget,319				)?;320			}321		}322323		// =========324325		<TotalSupply<T>>::insert(collection.id, total_supply);326		for (user, amount) in balances {327			<Balance<T>>::insert((collection.id, &user), amount);328329			<PalletEvm<T>>::deposit_log(330				ERC20Events::Transfer {331					from: H160::default(),332					to: *user.as_eth(),333					value: amount.into(),334				}335				.to_log(collection_id_to_address(collection.id)),336			);337			<PalletCommon<T>>::deposit_event(CommonEvent::ItemCreated(338				collection.id,339				TokenId::default(),340				user.clone(),341				amount,342			));343		}344345		Ok(())346	}347348	fn set_allowance_unchecked(349		collection: &FungibleHandle<T>,350		owner: &T::CrossAccountId,351		spender: &T::CrossAccountId,352		amount: u128,353	) {354		if amount == 0 {355			<Allowance<T>>::remove((collection.id, owner, spender));356		} else {357			<Allowance<T>>::insert((collection.id, owner, spender), amount);358		}359360		<PalletEvm<T>>::deposit_log(361			ERC20Events::Approval {362				owner: *owner.as_eth(),363				spender: *spender.as_eth(),364				value: amount.into(),365			}366			.to_log(collection_id_to_address(collection.id)),367		);368		<PalletCommon<T>>::deposit_event(CommonEvent::Approved(369			collection.id,370			TokenId(0),371			owner.clone(),372			spender.clone(),373			amount,374		));375	}376377	pub fn set_allowance(378		collection: &FungibleHandle<T>,379		owner: &T::CrossAccountId,380		spender: &T::CrossAccountId,381		amount: u128,382	) -> DispatchResult {383		if collection.permissions.access() == AccessMode::AllowList {384			collection.check_allowlist(owner)?;385			collection.check_allowlist(spender)?;386		}387388		if <Balance<T>>::get((collection.id, owner)) < amount {389			ensure!(390				collection.ignores_owned_amount(owner),391				<CommonError<T>>::CantApproveMoreThanOwned392			);393		}394395		// =========396397		Self::set_allowance_unchecked(collection, owner, spender, amount);398		Ok(())399	}400401	fn check_allowed(402		collection: &FungibleHandle<T>,403		spender: &T::CrossAccountId,404		from: &T::CrossAccountId,405		amount: u128,406		nesting_budget: &dyn Budget,407	) -> Result<Option<u128>, DispatchError> {408		if spender.conv_eq(from) {409			return Ok(None);410		}411		if collection.permissions.access() == AccessMode::AllowList {412			// `from`, `to` checked in [`transfer`]413			collection.check_allowlist(spender)?;414		}415		if let Some(source) = T::CrossTokenAddressMapping::address_to_token(from) {416			// TODO: should collection owner be allowed to perform this transfer?417			ensure!(418				<PalletStructure<T>>::check_indirectly_owned(419					spender.clone(),420					source.0,421					source.1,422					None,423					nesting_budget424				)?,425				<CommonError<T>>::ApprovedValueTooLow,426			);427			return Ok(None);428		}429		let allowance = <Allowance<T>>::get((collection.id, from, spender)).checked_sub(amount);430		if allowance.is_none() {431			ensure!(432				collection.ignores_allowance(spender),433				<CommonError<T>>::ApprovedValueTooLow434			);435		}436437		Ok(allowance)438	}439440	pub fn transfer_from(441		collection: &FungibleHandle<T>,442		spender: &T::CrossAccountId,443		from: &T::CrossAccountId,444		to: &T::CrossAccountId,445		amount: u128,446		nesting_budget: &dyn Budget,447	) -> DispatchResult {448		let allowance = Self::check_allowed(collection, spender, from, amount, nesting_budget)?;449450		// =========451452		Self::transfer(collection, from, to, amount, nesting_budget)?;453		if let Some(allowance) = allowance {454			Self::set_allowance_unchecked(collection, from, spender, allowance);455		}456		Ok(())457	}458459	pub fn burn_from(460		collection: &FungibleHandle<T>,461		spender: &T::CrossAccountId,462		from: &T::CrossAccountId,463		amount: u128,464		nesting_budget: &dyn Budget,465	) -> DispatchResult {466		let allowance = Self::check_allowed(collection, spender, from, amount, nesting_budget)?;467468		// =========469470		Self::burn(collection, from, amount)?;471		if let Some(allowance) = allowance {472			Self::set_allowance_unchecked(collection, from, spender, allowance);473		}474		Ok(())475	}476477	/// Delegated to `create_multiple_items`478	pub fn create_item(479		collection: &FungibleHandle<T>,480		sender: &T::CrossAccountId,481		data: CreateItemData<T>,482		nesting_budget: &dyn Budget,483	) -> DispatchResult {484		Self::create_multiple_items(485			collection,486			sender,487			[(data.0, data.1)].into_iter().collect(),488			nesting_budget,489		)490	}491}
after · pallets/fungible/src/lib.rs
1// Copyright 2019-2022 Unique Network (Gibraltar) Ltd.2// This file is part of Unique Network.34// Unique Network is free software: you can redistribute it and/or modify5// it under the terms of the GNU General Public License as published by6// the Free Software Foundation, either version 3 of the License, or7// (at your option) any later version.89// Unique Network is distributed in the hope that it will be useful,10// but WITHOUT ANY WARRANTY; without even the implied warranty of11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the12// GNU General Public License for more details.1314// You should have received a copy of the GNU General Public License15// along with Unique Network. If not, see <http://www.gnu.org/licenses/>.1617#![cfg_attr(not(feature = "std"), no_std)]1819use core::ops::Deref;20use evm_coder::ToLog;21use frame_support::{ensure};22use pallet_evm::account::CrossAccountId;23use up_data_structs::{24	AccessMode, CollectionId, TokenId, CreateCollectionData, mapping::TokenAddressMapping,25	budget::Budget,26};27use pallet_common::{28	Error as CommonError, Event as CommonEvent, Pallet as PalletCommon,29	eth::collection_id_to_address,30};31use pallet_evm::Pallet as PalletEvm;32use pallet_structure::Pallet as PalletStructure;33use pallet_evm_coder_substrate::WithRecorder;34use sp_core::H160;35use sp_runtime::{ArithmeticError, DispatchError, DispatchResult};36use sp_std::{collections::btree_map::BTreeMap};3738pub use pallet::*;3940use crate::erc::ERC20Events;41#[cfg(feature = "runtime-benchmarks")]42pub mod benchmarking;43pub mod common;44pub mod erc;45pub mod weights;4647pub type CreateItemData<T> = (<T as pallet_evm::account::Config>::CrossAccountId, u128);48pub(crate) type SelfWeightOf<T> = <T as Config>::WeightInfo;4950#[frame_support::pallet]51pub mod pallet {52	use frame_support::{Blake2_128, Blake2_128Concat, Twox64Concat, pallet_prelude::*, storage::Key};53	use up_data_structs::CollectionId;54	use super::weights::WeightInfo;5556	#[pallet::error]57	pub enum Error<T> {58		/// Not Fungible item data used to mint in Fungible collection.59		NotFungibleDataUsedToMintFungibleCollectionToken,60		/// Not default id passed as TokenId argument61		FungibleItemsHaveNoId,62		/// Tried to set data for fungible item63		FungibleItemsDontHaveData,64		/// Fungible token does not support nested65		FungibleDisallowsNesting,66		/// Setting item properties is not allowed67		SettingPropertiesNotAllowed,68	}6970	#[pallet::config]71	pub trait Config:72		frame_system::Config + pallet_common::Config + pallet_structure::Config + pallet_evm::Config73	{74		type WeightInfo: WeightInfo;75	}7677	#[pallet::pallet]78	#[pallet::generate_store(pub(super) trait Store)]79	pub struct Pallet<T>(_);8081	#[pallet::storage]82	pub type TotalSupply<T: Config> =83		StorageMap<Hasher = Twox64Concat, Key = CollectionId, Value = u128, QueryKind = ValueQuery>;8485	#[pallet::storage]86	pub type Balance<T: Config> = StorageNMap<87		Key = (88			Key<Twox64Concat, CollectionId>,89			Key<Blake2_128Concat, T::CrossAccountId>,90		),91		Value = u128,92		QueryKind = ValueQuery,93	>;9495	#[pallet::storage]96	pub type Allowance<T: Config> = StorageNMap<97		Key = (98			Key<Twox64Concat, CollectionId>,99			Key<Blake2_128, T::CrossAccountId>,100			Key<Blake2_128Concat, T::CrossAccountId>,101		),102		Value = u128,103		QueryKind = ValueQuery,104	>;105}106107pub struct FungibleHandle<T: Config>(pallet_common::CollectionHandle<T>);108impl<T: Config> FungibleHandle<T> {109	pub fn cast(inner: pallet_common::CollectionHandle<T>) -> Self {110		Self(inner)111	}112	pub fn into_inner(self) -> pallet_common::CollectionHandle<T> {113		self.0114	}115	pub fn common_mut(&mut self) -> &mut pallet_common::CollectionHandle<T> {116		&mut self.0117	}118}119impl<T: Config> WithRecorder<T> for FungibleHandle<T> {120	fn recorder(&self) -> &pallet_evm_coder_substrate::SubstrateRecorder<T> {121		self.0.recorder()122	}123	fn into_recorder(self) -> pallet_evm_coder_substrate::SubstrateRecorder<T> {124		self.0.into_recorder()125	}126}127impl<T: Config> Deref for FungibleHandle<T> {128	type Target = pallet_common::CollectionHandle<T>;129130	fn deref(&self) -> &Self::Target {131		&self.0132	}133}134135impl<T: Config> Pallet<T> {136	pub fn init_collection(137		owner: T::AccountId,138		data: CreateCollectionData<T::AccountId>,139	) -> Result<CollectionId, DispatchError> {140		<PalletCommon<T>>::init_collection(owner, data)141	}142	pub fn destroy_collection(143		collection: FungibleHandle<T>,144		sender: &T::CrossAccountId,145	) -> DispatchResult {146		let id = collection.id;147148		if Self::collection_has_tokens(id) {149			return Err(<CommonError<T>>::CantDestroyNotEmptyCollection.into());150		}151152		// =========153154		PalletCommon::destroy_collection(collection.0, sender)?;155156		<TotalSupply<T>>::remove(id);157		<Balance<T>>::remove_prefix((id,), None);158		<Allowance<T>>::remove_prefix((id,), None);159		Ok(())160	}161162	fn collection_has_tokens(collection_id: CollectionId) -> bool {163		<TotalSupply<T>>::get(collection_id) != 0164	}165166	pub fn burn(167		collection: &FungibleHandle<T>,168		owner: &T::CrossAccountId,169		amount: u128,170	) -> DispatchResult {171		let total_supply = <TotalSupply<T>>::get(collection.id)172			.checked_sub(amount)173			.ok_or(<CommonError<T>>::TokenValueTooLow)?;174175		let balance = <Balance<T>>::get((collection.id, owner))176			.checked_sub(amount)177			.ok_or(<CommonError<T>>::TokenValueTooLow)?;178179		if collection.permissions.access() == AccessMode::AllowList {180			collection.check_allowlist(owner)?;181		}182183		// =========184185		if balance == 0 {186			<Balance<T>>::remove((collection.id, owner));187			<PalletStructure<T>>::unnest_if_nested(188				owner,189				collection.id,190				TokenId::default()191			);192		} else {193			<Balance<T>>::insert((collection.id, owner), balance);194		}195		<TotalSupply<T>>::insert(collection.id, total_supply);196197		<PalletEvm<T>>::deposit_log(198			ERC20Events::Transfer {199				from: *owner.as_eth(),200				to: H160::default(),201				value: amount.into(),202			}203			.to_log(collection_id_to_address(collection.id)),204		);205		<PalletCommon<T>>::deposit_event(CommonEvent::ItemDestroyed(206			collection.id,207			TokenId::default(),208			owner.clone(),209			amount,210		));211		Ok(())212	}213214	pub fn transfer(215		collection: &FungibleHandle<T>,216		from: &T::CrossAccountId,217		to: &T::CrossAccountId,218		amount: u128,219		nesting_budget: &dyn Budget,220	) -> DispatchResult {221		ensure!(222			collection.limits.transfers_enabled(),223			<CommonError<T>>::TransferNotAllowed,224		);225226		if collection.permissions.access() == AccessMode::AllowList {227			collection.check_allowlist(from)?;228			collection.check_allowlist(to)?;229		}230		<PalletCommon<T>>::ensure_correct_receiver(to)?;231232		let balance_from = <Balance<T>>::get((collection.id, from))233			.checked_sub(amount)234			.ok_or(<CommonError<T>>::TokenValueTooLow)?;235		let balance_to = if from != to {236			Some(237				<Balance<T>>::get((collection.id, to))238					.checked_add(amount)239					.ok_or(ArithmeticError::Overflow)?,240			)241		} else {242			None243		};244245		// =========246247		<PalletStructure<T>>::nest_if_sent_to_token(248			from.clone(),249			to,250			collection.id,251			TokenId::default(),252			nesting_budget253		)?;254255		if let Some(balance_to) = balance_to {256			// from != to257			if balance_from == 0 {258				<Balance<T>>::remove((collection.id, from));259				<PalletStructure<T>>::unnest_if_nested(260					from,261					collection.id,262					TokenId::default()263				);264			} else {265				<Balance<T>>::insert((collection.id, from), balance_from);266			}267			<Balance<T>>::insert((collection.id, to), balance_to);268		}269270		<PalletEvm<T>>::deposit_log(271			ERC20Events::Transfer {272				from: *from.as_eth(),273				to: *to.as_eth(),274				value: amount.into(),275			}276			.to_log(collection_id_to_address(collection.id)),277		);278		<PalletCommon<T>>::deposit_event(CommonEvent::Transfer(279			collection.id,280			TokenId::default(),281			from.clone(),282			to.clone(),283			amount,284		));285		Ok(())286	}287288	pub fn create_multiple_items(289		collection: &FungibleHandle<T>,290		sender: &T::CrossAccountId,291		data: BTreeMap<T::CrossAccountId, u128>,292		nesting_budget: &dyn Budget,293	) -> DispatchResult {294		if !collection.is_owner_or_admin(sender) {295			ensure!(296				collection.permissions.mint_mode(),297				<CommonError<T>>::PublicMintingNotAllowed298			);299			collection.check_allowlist(sender)?;300301			for (owner, _) in data.iter() {302				collection.check_allowlist(owner)?;303			}304		}305306		let total_supply = data307			.iter()308			.map(|(_, v)| *v)309			.try_fold(<TotalSupply<T>>::get(collection.id), |acc, v| {310				acc.checked_add(v)311			})312			.ok_or(ArithmeticError::Overflow)?;313314		let mut balances = data;315		for (k, v) in balances.iter_mut() {316			*v = <Balance<T>>::get((collection.id, &k))317				.checked_add(*v)318				.ok_or(ArithmeticError::Overflow)?;319		}320321		for (to, _) in balances.iter() {322			<PalletStructure<T>>::check_nesting(323				sender.clone(),324				to,325				collection.id,326				TokenId::default(),327				nesting_budget,328			)?;329		}330331		// =========332333		<TotalSupply<T>>::insert(collection.id, total_supply);334		for (user, amount) in balances {335			<Balance<T>>::insert((collection.id, &user), amount);336			<PalletStructure<T>>::nest_if_sent_to_token_unchecked(&user, collection.id, TokenId::default());337			<PalletEvm<T>>::deposit_log(338				ERC20Events::Transfer {339					from: H160::default(),340					to: *user.as_eth(),341					value: amount.into(),342				}343				.to_log(collection_id_to_address(collection.id)),344			);345			<PalletCommon<T>>::deposit_event(CommonEvent::ItemCreated(346				collection.id,347				TokenId::default(),348				user.clone(),349				amount,350			));351		}352353		Ok(())354	}355356	fn set_allowance_unchecked(357		collection: &FungibleHandle<T>,358		owner: &T::CrossAccountId,359		spender: &T::CrossAccountId,360		amount: u128,361	) {362		if amount == 0 {363			<Allowance<T>>::remove((collection.id, owner, spender));364		} else {365			<Allowance<T>>::insert((collection.id, owner, spender), amount);366		}367368		<PalletEvm<T>>::deposit_log(369			ERC20Events::Approval {370				owner: *owner.as_eth(),371				spender: *spender.as_eth(),372				value: amount.into(),373			}374			.to_log(collection_id_to_address(collection.id)),375		);376		<PalletCommon<T>>::deposit_event(CommonEvent::Approved(377			collection.id,378			TokenId(0),379			owner.clone(),380			spender.clone(),381			amount,382		));383	}384385	pub fn set_allowance(386		collection: &FungibleHandle<T>,387		owner: &T::CrossAccountId,388		spender: &T::CrossAccountId,389		amount: u128,390	) -> DispatchResult {391		if collection.permissions.access() == AccessMode::AllowList {392			collection.check_allowlist(owner)?;393			collection.check_allowlist(spender)?;394		}395396		if <Balance<T>>::get((collection.id, owner)) < amount {397			ensure!(398				collection.ignores_owned_amount(owner),399				<CommonError<T>>::CantApproveMoreThanOwned400			);401		}402403		// =========404405		Self::set_allowance_unchecked(collection, owner, spender, amount);406		Ok(())407	}408409	fn check_allowed(410		collection: &FungibleHandle<T>,411		spender: &T::CrossAccountId,412		from: &T::CrossAccountId,413		amount: u128,414		nesting_budget: &dyn Budget,415	) -> Result<Option<u128>, DispatchError> {416		if spender.conv_eq(from) {417			return Ok(None);418		}419		if collection.permissions.access() == AccessMode::AllowList {420			// `from`, `to` checked in [`transfer`]421			collection.check_allowlist(spender)?;422		}423		if let Some(source) = T::CrossTokenAddressMapping::address_to_token(from) {424			// TODO: should collection owner be allowed to perform this transfer?425			ensure!(426				<PalletStructure<T>>::check_indirectly_owned(427					spender.clone(),428					source.0,429					source.1,430					None,431					nesting_budget432				)?,433				<CommonError<T>>::ApprovedValueTooLow,434			);435			return Ok(None);436		}437		let allowance = <Allowance<T>>::get((collection.id, from, spender)).checked_sub(amount);438		if allowance.is_none() {439			ensure!(440				collection.ignores_allowance(spender),441				<CommonError<T>>::ApprovedValueTooLow442			);443		}444445		Ok(allowance)446	}447448	pub fn transfer_from(449		collection: &FungibleHandle<T>,450		spender: &T::CrossAccountId,451		from: &T::CrossAccountId,452		to: &T::CrossAccountId,453		amount: u128,454		nesting_budget: &dyn Budget,455	) -> DispatchResult {456		let allowance = Self::check_allowed(collection, spender, from, amount, nesting_budget)?;457458		// =========459460		Self::transfer(collection, from, to, amount, nesting_budget)?;461		if let Some(allowance) = allowance {462			Self::set_allowance_unchecked(collection, from, spender, allowance);463		}464		Ok(())465	}466467	pub fn burn_from(468		collection: &FungibleHandle<T>,469		spender: &T::CrossAccountId,470		from: &T::CrossAccountId,471		amount: u128,472		nesting_budget: &dyn Budget,473	) -> DispatchResult {474		let allowance = Self::check_allowed(collection, spender, from, amount, nesting_budget)?;475476		// =========477478		Self::burn(collection, from, amount)?;479		if let Some(allowance) = allowance {480			Self::set_allowance_unchecked(collection, from, spender, allowance);481		}482		Ok(())483	}484485	/// Delegated to `create_multiple_items`486	pub fn create_item(487		collection: &FungibleHandle<T>,488		sender: &T::CrossAccountId,489		data: CreateItemData<T>,490		nesting_budget: &dyn Budget,491	) -> DispatchResult {492		Self::create_multiple_items(493			collection,494			sender,495			[(data.0, data.1)].into_iter().collect(),496			nesting_budget,497		)498	}499}
modifiedpallets/nonfungible/src/common.rsdiffbeforeafterboth
--- a/pallets/nonfungible/src/common.rs
+++ b/pallets/nonfungible/src/common.rs
@@ -353,6 +353,22 @@
 		<Pallet<T>>::check_nesting(self, sender, from, under, budget)
 	}
 
+	fn nest(
+		&self,
+		under: TokenId,
+		to_nest: (CollectionId, TokenId)
+	) {
+		<Pallet<T>>::nest((self.id, under), to_nest);
+	}
+
+	fn unnest(
+		&self,
+		under: TokenId,
+		to_unnest: (CollectionId, TokenId)
+	) {
+		<Pallet<T>>::unnest((self.id, under), to_unnest);
+	}
+
 	fn account_tokens(&self, account: T::CrossAccountId) -> Vec<TokenId> {
 		<Owned<T>>::iter_prefix((self.id, account))
 			.map(|(id, _)| id)
modifiedpallets/nonfungible/src/lib.rsdiffbeforeafterboth
--- a/pallets/nonfungible/src/lib.rs
+++ b/pallets/nonfungible/src/lib.rs
@@ -27,7 +27,7 @@
 use pallet_evm::{account::CrossAccountId, Pallet as PalletEvm};
 use pallet_common::{
 	Error as CommonError, Pallet as PalletCommon, Event as CommonEvent, CollectionHandle,
-	dispatch::CollectionDispatch, eth::collection_id_to_address,
+	eth::collection_id_to_address,
 };
 use pallet_structure::Pallet as PalletStructure;
 use pallet_evm_coder_substrate::{SubstrateRecorder, WithRecorder};
@@ -76,6 +76,8 @@
 		NotNonfungibleDataUsedToMintFungibleCollectionToken,
 		/// Used amount > 1 with NFT
 		NonfungibleItemsHaveNoAmount,
+		/// Unable to burn NFT with children
+		CantBurnNftWithChildren,
 	}
 
 	#[pallet::config]
@@ -127,7 +129,20 @@
 		QueryKind = ValueQuery,
 	>;
 
+	/// Used to enumerate token's children
 	#[pallet::storage]
+	#[pallet::getter(fn token_children)]
+	pub type TokenChildren<T: Config> = StorageNMap<
+		Key = (
+			Key<Twox64Concat, CollectionId>,
+			Key<Twox64Concat, TokenId>,
+			Key<Twox64Concat, (CollectionId, TokenId)>,
+		),
+		Value = bool,
+		QueryKind = ValueQuery,
+	>;
+
+	#[pallet::storage]
 	pub type AccountBalance<T: Config> = StorageNMap<
 		Key = (
 			Key<Twox64Concat, CollectionId>,
@@ -277,11 +292,16 @@
 	) -> DispatchResult {
 		let id = collection.id;
 
+		if Self::collection_has_tokens(id) {
+			return Err(<CommonError<T>>::CantDestroyNotEmptyCollection.into());
+		}
+
 		// =========
 
 		PalletCommon::destroy_collection(collection.0, sender)?;
 
 		<TokenData<T>>::remove_prefix((id,), None);
+		<TokenChildren<T>>::remove_prefix((id,), None);
 		<Owned<T>>::remove_prefix((id,), None);
 		<TokensMinted<T>>::remove(id);
 		<TokensBurnt<T>>::remove(id);
@@ -307,6 +327,10 @@
 			collection.check_allowlist(sender)?;
 		}
 
+		if Self::token_has_children(collection.id, token) {
+			return Err(<Error<T>>::CantBurnNftWithChildren.into());
+		}
+
 		let burnt = <TokensBurnt<T>>::get(collection.id)
 			.checked_add(1)
 			.ok_or(ArithmeticError::Overflow)?;
@@ -315,13 +339,20 @@
 			.checked_sub(1)
 			.ok_or(ArithmeticError::Overflow)?;
 
+		// =========
+
 		if balance == 0 {
 			<AccountBalance<T>>::remove((collection.id, token_data.owner.clone()));
 		} else {
 			<AccountBalance<T>>::insert((collection.id, token_data.owner.clone()), balance);
 		}
-		// =========
 
+		<PalletStructure<T>>::unnest_if_nested(
+			&token_data.owner,
+			collection.id,
+			token
+		);
+
 		<Owned<T>>::remove((collection.id, &token_data.owner, token));
 		<TokensBurnt<T>>::insert(collection.id, burnt);
 		<TokenData<T>>::remove((collection.id, token));
@@ -553,20 +584,21 @@
 			None
 		};
 
-		if let Some(target) = T::CrossTokenAddressMapping::address_to_token(to) {
-			let handle = <CollectionHandle<T>>::try_get(target.0)?;
-			let dispatch = T::CollectionDispatch::dispatch(handle);
-			let dispatch = dispatch.as_dyn();
+		<PalletStructure<T>>::nest_if_sent_to_token(
+			from.clone(),
+			to,
+			collection.id,
+			token,
+			nesting_budget
+		)?;
 
-			dispatch.check_nesting(
-				from.clone(),
-				(collection.id, token),
-				target.1,
-				nesting_budget,
-			)?;
-		}
+		// =========
 
-		// =========
+		<PalletStructure<T>>::unnest_if_nested(
+			from,
+			collection.id,
+			token
+		);
 
 		<TokenData<T>>::insert(
 			(collection.id, token),
@@ -653,17 +685,14 @@
 
 		for (i, data) in data.iter().enumerate() {
 			let token = TokenId(first_token + i as u32 + 1);
-			if let Some(target) = T::CrossTokenAddressMapping::address_to_token(&data.owner) {
-				let handle = <CollectionHandle<T>>::try_get(target.0)?;
-				let dispatch = T::CollectionDispatch::dispatch(handle);
-				let dispatch = dispatch.as_dyn();
-				dispatch.check_nesting(
-					sender.clone(),
-					(collection.id, token),
-					target.1,
-					nesting_budget,
-				)?;
-			}
+
+			<PalletStructure<T>>::check_nesting(
+				sender.clone(),
+				&data.owner,
+				collection.id,
+				token,
+				nesting_budget,
+			)?;
 		}
 
 		// =========
@@ -680,6 +709,8 @@
 					},
 				);
 
+				<PalletStructure<T>>::nest_if_sent_to_token_unchecked(&data.owner, collection.id, TokenId(token));
+
 				if let Err(e) = Self::set_token_properties(
 					collection,
 					sender,
@@ -927,6 +958,33 @@
 		Ok(())
 	}
 
+	fn nest(
+		under: (CollectionId, TokenId),
+		to_nest: (CollectionId, TokenId),
+	) {
+		<TokenChildren<T>>::insert(
+			(under.0, under.1, (to_nest.0, to_nest.1)),
+			true
+		);
+	}
+
+	fn unnest(
+		under: (CollectionId, TokenId),
+		to_unnest: (CollectionId, TokenId),
+	) {
+		<TokenChildren<T>>::remove(
+			(under.0, under.1, to_unnest)
+		);
+	}
+
+	fn collection_has_tokens(collection_id: CollectionId) -> bool {
+		<TokenData<T>>::iter_prefix((collection_id,)).next().is_some()
+	}
+
+	fn token_has_children(collection_id: CollectionId, token_id: TokenId) -> bool {
+		<TokenChildren<T>>::iter_prefix((collection_id, token_id)).next().is_some()
+	}
+
 	/// Delegated to `create_multiple_items`
 	pub fn create_item(
 		collection: &NonfungibleHandle<T>,
modifiedpallets/proxy-rmrk-core/src/misc.rsdiffbeforeafterboth
--- a/pallets/proxy-rmrk-core/src/misc.rs
+++ b/pallets/proxy-rmrk-core/src/misc.rs
@@ -26,6 +26,18 @@
     }
 }
 
+pub trait RmrkRebind<T, S> {
+    fn rebind(&self) -> BoundedVec<u8, S>;
+}
+
+impl<T, S> RmrkRebind<T, S> for BoundedVec<u8, T> where BoundedVec<u8, S>: TryFrom<Vec<u8>> {
+    fn rebind(&self) -> BoundedVec<u8, S> {
+        BoundedVec::<u8, S>::try_from(
+            self.clone().into_inner()
+        ).unwrap_or_default()
+    }
+}
+
 #[derive(Encode, Decode, PartialEq, Eq)]
 pub enum CollectionType {
     Regular,
modifiedpallets/refungible/src/common.rsdiffbeforeafterboth
--- a/pallets/refungible/src/common.rs
+++ b/pallets/refungible/src/common.rs
@@ -313,6 +313,18 @@
 		fail!(<Error<T>>::RefungibleDisallowsNesting)
 	}
 
+	fn nest(
+		&self,
+		_under: TokenId,
+		_to_nest: (CollectionId, TokenId)
+	) {}
+
+	fn unnest(
+		&self,
+		_under: TokenId,
+		_to_nest: (CollectionId, TokenId)
+	) {}
+
 	fn account_tokens(&self, account: T::CrossAccountId) -> Vec<TokenId> {
 		<Owned<T>>::iter_prefix((self.id, account))
 			.map(|(id, _)| id)
modifiedpallets/refungible/src/lib.rsdiffbeforeafterboth
--- a/pallets/refungible/src/lib.rs
+++ b/pallets/refungible/src/lib.rs
@@ -23,8 +23,7 @@
 };
 use pallet_evm::account::CrossAccountId;
 use pallet_common::{
-	Error as CommonError, Event as CommonEvent, Pallet as PalletCommon, CollectionHandle,
-	dispatch::CollectionDispatch,
+	Error as CommonError, Event as CommonEvent, Pallet as PalletCommon,
 };
 use pallet_structure::Pallet as PalletStructure;
 use sp_runtime::{ArithmeticError, DispatchError, DispatchResult};
@@ -211,6 +210,10 @@
 	) -> DispatchResult {
 		let id = collection.id;
 
+		if Self::collection_has_tokens(id) {
+			return Err(<CommonError<T>>::CantDestroyNotEmptyCollection.into());
+		}
+
 		// =========
 
 		PalletCommon::destroy_collection(collection.0, sender)?;
@@ -226,6 +229,10 @@
 		Ok(())
 	}
 
+	fn collection_has_tokens(collection_id: CollectionId) -> bool {
+		<TokenData<T>>::iter_prefix((collection_id,)).next().is_some()
+	}
+
 	pub fn burn_token(collection: &RefungibleHandle<T>, token_id: TokenId) -> DispatchResult {
 		let burnt = <TokensBurnt<T>>::get(collection.id)
 			.checked_add(1)
@@ -265,6 +272,7 @@
 			// =========
 
 			<Owned<T>>::remove((collection.id, owner, token));
+			<PalletStructure<T>>::unnest_if_nested(owner, collection.id, token);
 			<AccountBalance<T>>::insert((collection.id, owner), account_balance);
 			Self::burn_token(collection, token)?;
 			<PalletCommon<T>>::deposit_event(CommonEvent::ItemDestroyed(
@@ -292,6 +300,7 @@
 
 		if balance == 0 {
 			<Owned<T>>::remove((collection.id, owner, token));
+			<PalletStructure<T>>::unnest_if_nested(owner, collection.id, token);
 			<Balance<T>>::remove((collection.id, token, owner));
 			<AccountBalance<T>>::insert((collection.id, owner), account_balance);
 		} else {
@@ -372,25 +381,25 @@
 			None
 		};
 
-		if let Some(target) = T::CrossTokenAddressMapping::address_to_token(to) {
-			let handle = <CollectionHandle<T>>::try_get(target.0)?;
-			let dispatch = T::CollectionDispatch::dispatch(handle);
-			let dispatch = dispatch.as_dyn();
+		// =========
 
-			dispatch.check_nesting(
-				from.clone(),
-				(collection.id, token),
-				target.1,
-				nesting_budget,
-			)?;
-		}
-
-		// =========
+		<PalletStructure<T>>::nest_if_sent_to_token(
+			from.clone(),
+			to,
+			collection.id,
+			token,
+			nesting_budget
+		)?;
 
 		if let Some(balance_to) = balance_to {
 			// from != to
 			if balance_from == 0 {
 				<Balance<T>>::remove((collection.id, token, from));
+				<PalletStructure<T>>::unnest_if_nested(
+					from,
+					collection.id,
+					token
+				);
 			} else {
 				<Balance<T>>::insert((collection.id, token, from), balance_from);
 			}
@@ -488,18 +497,14 @@
 		for (i, token) in data.iter().enumerate() {
 			let token_id = TokenId(first_token_id + i as u32 + 1);
 			for (to, _) in token.users.iter() {
-				if let Some(target) = T::CrossTokenAddressMapping::address_to_token(to) {
-					let handle = <CollectionHandle<T>>::try_get(target.0)?;
-					let dispatch = T::CollectionDispatch::dispatch(handle);
-					let dispatch = dispatch.as_dyn();
 
-					dispatch.check_nesting(
-						sender.clone(),
-						(collection.id, token_id),
-						target.1,
-						nesting_budget,
-					)?;
-				}
+				<PalletStructure<T>>::check_nesting(
+					sender.clone(),
+					to,
+					collection.id,
+					token_id,
+					nesting_budget,
+				)?;
 			}
 		}
 
@@ -519,12 +524,15 @@
 					const_data: token.const_data,
 				},
 			);
+
 			for (user, amount) in token.users.into_iter() {
 				if amount == 0 {
 					continue;
 				}
 				<Balance<T>>::insert((collection.id, token_id, &user), amount);
 				<Owned<T>>::insert((collection.id, &user, TokenId(token_id)), true);
+				<PalletStructure<T>>::nest_if_sent_to_token_unchecked(&user, collection.id, TokenId(token_id));
+
 				// TODO: ERC20 transfer event
 				<PalletCommon<T>>::deposit_event(CommonEvent::ItemCreated(
 					collection.id,
modifiedpallets/structure/src/lib.rsdiffbeforeafterboth
--- a/pallets/structure/src/lib.rs
+++ b/pallets/structure/src/lib.rs
@@ -1,8 +1,9 @@
 #![cfg_attr(not(feature = "std"), no_std)]
 
+use pallet_common::CommonCollectionOperations;
 use sp_std::collections::btree_set::BTreeSet;
 
-use frame_support::dispatch::DispatchError;
+use frame_support::dispatch::{DispatchError, DispatchResult};
 use frame_support::fail;
 pub use pallet::*;
 use pallet_common::{dispatch::CollectionDispatch, CollectionHandle};
@@ -155,8 +156,8 @@
 		budget: &dyn Budget,
 	) -> Result<bool, DispatchError> {
 		let target_parent = match T::CrossTokenAddressMapping::address_to_token(&user) {
-			Some((collection, token)) => Parent::Token(collection, token),
-			None => Parent::User(user),
+			Some((collection, token)) => Self::find_topmost_owner(collection, token, budget)?,
+			None => user,
 		};
 
 		// Tried to nest token in itself
@@ -171,10 +172,10 @@
 					return Err(<Error<T>>::OuroborosDetected.into())
 				}
 				// Found needed parent, token is indirecty owned
-				v if v == target_parent => return Ok(true),
+				Parent::User(user) if user == target_parent => return Ok(true),
 				// Token is owned by other user
 				Parent::User(_) => return Ok(false),
-				Parent::TokenNotFound => return Ok(false),
+				Parent::TokenNotFound => return Err(<Error<T>>::TokenNotFound.into()),
 				// Continue parent chain
 				Parent::Token(_, _) => {}
 			}
@@ -182,4 +183,113 @@
 
 		Err(<Error<T>>::DepthLimit.into())
 	}
+
+	pub fn check_nesting(
+		from: T::CrossAccountId,
+		under: &T::CrossAccountId,
+		collection_id: CollectionId,
+		token_id: TokenId,
+		nesting_budget: &dyn Budget
+	) -> DispatchResult {
+		Self::try_exec_if_owner_is_valid_nft(
+			under,
+			|d, parent_id| d.check_nesting(
+				from,
+				(collection_id, token_id),
+				parent_id,
+				nesting_budget
+			)
+		)
+	}
+
+	pub fn nest_if_sent_to_token(
+		from: T::CrossAccountId,
+		under: &T::CrossAccountId,
+		collection_id: CollectionId,
+		token_id: TokenId,
+		nesting_budget: &dyn Budget
+	) -> DispatchResult {
+		Self::try_exec_if_owner_is_valid_nft(
+			under,
+			|d, parent_id| {
+				d.check_nesting(
+					from,
+					(collection_id, token_id),
+					parent_id,
+					nesting_budget
+				)?;
+
+				d.nest(parent_id, (collection_id, token_id));
+
+				Ok(())
+			}
+		)
+	}
+
+	pub fn nest_if_sent_to_token_unchecked(
+		owner: &T::CrossAccountId,
+		collection_id: CollectionId,
+		token_id: TokenId
+	) {
+		Self::exec_if_owner_is_valid_nft(
+			owner,
+			|d, parent_id| d.nest(
+				parent_id,
+				(collection_id, token_id)
+			)
+		);
+	}
+
+	pub fn unnest_if_nested(
+		owner: &T::CrossAccountId,
+		collection_id: CollectionId,
+		token_id: TokenId
+	) {
+		Self::exec_if_owner_is_valid_nft(
+			owner,
+			|d, parent_id| d.unnest(
+			parent_id,
+			(collection_id, token_id)
+			)
+		);
+	}
+
+	fn exec_if_owner_is_valid_nft(
+		account: &T::CrossAccountId,
+		action: impl FnOnce(&dyn CommonCollectionOperations<T>, TokenId)
+	) {
+		Self::try_exec_if_owner_is_valid_nft(
+			account,
+			|d, id| {
+				action(d, id);
+				Ok(())
+			}
+		).unwrap();
+	}
+
+	fn try_exec_if_owner_is_valid_nft(
+		account: &T::CrossAccountId,
+		action: impl FnOnce(&dyn CommonCollectionOperations<T>, TokenId) -> DispatchResult
+	) -> DispatchResult {
+		let account = T::CrossTokenAddressMapping::address_to_token(account);
+
+		if account.is_none() {
+			return Ok(());
+		}
+
+		let account = account.unwrap();
+
+		let handle = <CollectionHandle<T>>::try_get(account.0);
+
+		if handle.is_err() {
+			return Ok(());
+		}
+
+		let handle = handle.unwrap();
+
+		let dispatch = T::CollectionDispatch::dispatch(handle);
+		let dispatch = dispatch.as_dyn();
+
+		action(dispatch, account.1)
+	}
 }
modifiedpallets/unique/src/lib.rsdiffbeforeafterboth
--- a/pallets/unique/src/lib.rs
+++ b/pallets/unique/src/lib.rs
@@ -55,6 +55,8 @@
 pub mod weights;
 use weights::WeightInfo;
 
+const NESTING_BUDGET: u32 = 5;
+
 decl_error! {
 	/// Error for non-fungible-token module.
 	pub enum Error for Module<T: Config> {
@@ -569,7 +571,7 @@
 		#[transactional]
 		pub fn create_item(origin, collection_id: CollectionId, owner: T::CrossAccountId, data: CreateItemData) -> DispatchResultWithPostInfo {
 			let sender = T::CrossAccountId::from_sub(ensure_signed(origin)?);
-			let budget = budget::Value::new(2);
+			let budget = budget::Value::new(NESTING_BUDGET);
 
 			dispatch_call::<T, _>(collection_id, |d| d.create_item(sender, owner, data, &budget))
 		}
@@ -597,7 +599,7 @@
 		pub fn create_multiple_items(origin, collection_id: CollectionId, owner: T::CrossAccountId, items_data: Vec<CreateItemData>) -> DispatchResultWithPostInfo {
 			ensure!(!items_data.is_empty(), Error::<T>::EmptyArgument);
 			let sender = T::CrossAccountId::from_sub(ensure_signed(origin)?);
-			let budget = budget::Value::new(2);
+			let budget = budget::Value::new(NESTING_BUDGET);
 
 			dispatch_call::<T, _>(collection_id, |d| d.create_multiple_items(sender, owner, items_data, &budget))
 		}
@@ -678,7 +680,7 @@
 		#[transactional]
 		pub fn create_multiple_items_ex(origin, collection_id: CollectionId, data: CreateItemExData<T::CrossAccountId>) -> DispatchResultWithPostInfo {
 			let sender = T::CrossAccountId::from_sub(ensure_signed(origin)?);
-			let budget = budget::Value::new(2);
+			let budget = budget::Value::new(NESTING_BUDGET);
 
 			dispatch_call::<T, _>(collection_id, |d| d.create_multiple_items_ex(sender, data, &budget))
 		}
@@ -758,7 +760,7 @@
 		#[transactional]
 		pub fn burn_from(origin, collection_id: CollectionId, from: T::CrossAccountId, item_id: TokenId, value: u128) -> DispatchResultWithPostInfo {
 			let sender = T::CrossAccountId::from_sub(ensure_signed(origin)?);
-			let budget = budget::Value::new(2);
+			let budget = budget::Value::new(NESTING_BUDGET);
 
 			dispatch_call::<T, _>(collection_id, |d| d.burn_from(sender, from, item_id, value, &budget))
 		}
@@ -790,7 +792,7 @@
 		#[transactional]
 		pub fn transfer(origin, recipient: T::CrossAccountId, collection_id: CollectionId, item_id: TokenId, value: u128) -> DispatchResultWithPostInfo {
 			let sender = T::CrossAccountId::from_sub(ensure_signed(origin)?);
-			let budget = budget::Value::new(2);
+			let budget = budget::Value::new(NESTING_BUDGET);
 
 			dispatch_call::<T, _>(collection_id, |d| d.transfer(sender, recipient, item_id, value, &budget))
 		}
@@ -841,7 +843,7 @@
 		#[transactional]
 		pub fn transfer_from(origin, from: T::CrossAccountId, recipient: T::CrossAccountId, collection_id: CollectionId, item_id: TokenId, value: u128 ) -> DispatchResultWithPostInfo {
 			let sender = T::CrossAccountId::from_sub(ensure_signed(origin)?);
-			let budget = budget::Value::new(2);
+			let budget = budget::Value::new(NESTING_BUDGET);
 
 			dispatch_call::<T, _>(collection_id, |d| d.transfer_from(sender, from, recipient, item_id, value, &budget))
 		}
modifiedruntime/common/src/runtime_apis.rsdiffbeforeafterboth
--- a/runtime/common/src/runtime_apis.rs
+++ b/runtime/common/src/runtime_apis.rs
@@ -25,7 +25,7 @@
                     dispatch_unique_runtime!(collection.token_owner(token))
                 }
                 fn topmost_token_owner(collection: CollectionId, token: TokenId) -> Result<Option<CrossAccountId>, DispatchError> {
-                    let budget = up_data_structs::budget::Value::new(5);
+                    let budget = up_data_structs::budget::Value::new(10);
 
                     Ok(Some(<pallet_structure::Pallet<Runtime>>::find_topmost_owner(collection, token, &budget)?))
                 }
@@ -142,7 +142,7 @@
                 }
 
                 fn collection_by_id(collection_id: RmrkCollectionId) -> Result<Option<RmrkCollectionInfo<AccountId>>, DispatchError> {
-                    use pallet_proxy_rmrk_core::{RmrkProperty, misc::{CollectionType, RmrkDecode}};
+                    use pallet_proxy_rmrk_core::{RmrkProperty, misc::{CollectionType, RmrkDecode, RmrkRebind}};
 
                     let collection_id = CollectionId(collection_id);
                     let collection = match RmrkCore::get_typed_nft_collection(collection_id, CollectionType::Regular) {
@@ -156,7 +156,7 @@
                         issuer: collection.owner.clone(),
                         metadata: RmrkCore::get_collection_property(collection_id, RmrkProperty::Metadata)?.decode_or_default(),
                         max: collection.limits.token_limit,
-                        symbol: collection.token_prefix.decode_or_default(),
+                        symbol: collection.token_prefix.rebind(),
                         nfts_count
                     }))
                 }
@@ -204,22 +204,21 @@
                 }
 
                 fn nft_children(collection_id: RmrkCollectionId, nft_id: RmrkNftId) -> Result<Vec<RmrkNftChild>, DispatchError> {
-                    use up_data_structs::mapping::TokenAddressMapping;
-
                     let collection_id = CollectionId(collection_id);
                     let nft_id = TokenId(nft_id);
                     if !RmrkCore::nft_exists(collection_id, nft_id) { return Ok(Vec::new()); }
 
-                    let cross_account_id = CrossAccountId::from_eth(
-                        EvmTokenAddressMapping::token_to_address(collection_id, nft_id)
-                    );
-
                     Ok(
-                        pallet_nonfungible::Owned::<Runtime>::iter_prefix((collection_id, cross_account_id))
-                            .map(|(child_id, _)| RmrkNftChild {
-                                collection_id: collection_id.0, // todo make sure they're always from this collection // spoiler: they're not
-                                nft_id: child_id.0,
-                            }).collect()
+                        pallet_nonfungible::TokenChildren::<Runtime>::iter_prefix((collection_id, nft_id))
+                            .filter_map(|(child_id, is_child)|
+                                match is_child {
+                                    true => Some(RmrkNftChild {
+                                        collection_id: child_id.0.0,
+                                        nft_id: child_id.1.0,
+                                    }),
+                                    false => None,
+                                }
+                            ).collect()
                     )
                 }
 
@@ -332,7 +331,7 @@
 
                 fn base(base_id: RmrkBaseId) -> Result<Option<RmrkBaseInfo<AccountId>>, DispatchError> {
                     use pallet_proxy_rmrk_core::{
-                        RmrkProperty, misc::{CollectionType, RmrkDecode},
+                        RmrkProperty, misc::{CollectionType, RmrkDecode, RmrkRebind},
                     };
 
                     let collection_id = CollectionId(base_id);
@@ -344,7 +343,7 @@
                     Ok(Some(RmrkBaseInfo {
                         issuer: collection.owner.clone(),
                         base_type: RmrkCore::get_collection_property(collection_id, RmrkProperty::BaseType)?.decode_or_default(),
-                        symbol: collection.token_prefix.decode_or_default(),
+                        symbol: collection.token_prefix.rebind(),
                     }))
                 }
 
modifiedtests/src/nesting/nest.test.tsdiffbeforeafterboth
--- a/tests/src/nesting/nest.test.ts
+++ b/tests/src/nesting/nest.test.ts
@@ -41,7 +41,7 @@
 
       // Create a token to be nested
       const newToken = await createItemExpectSuccess(alice, collection, 'NFT');
-      
+
       // Nest
       await transferExpectSuccess(collection, newToken, alice, {Ethereum: tokenIdToAddress(collection, targetToken)});
       expect(await getTopmostTokenOwner(api, collection, newToken)).to.be.deep.equal({Substrate: alice.address});
@@ -111,8 +111,8 @@
 
       // Create a nested token
       await expect(executeTransaction(api, alice, api.tx.unique.createItem(
-        collectionFT, 
-        targetAddress, 
+        collectionFT,
+        targetAddress,
         {Fungible: {Value: 10}},
       ))).to.not.be.rejected;
 
@@ -134,8 +134,8 @@
 
       // Create a nested token
       await expect(executeTransaction(api, alice, api.tx.unique.createItem(
-        collectionFT, 
-        targetAddress, 
+        collectionFT,
+        targetAddress,
         {Fungible: {Value: 10}},
       ))).to.not.be.rejected;
 
@@ -158,8 +158,8 @@
 
       // Create a nested token
       await expect(executeTransaction(api, alice, api.tx.unique.createItem(
-        collectionRFT, 
-        targetAddress, 
+        collectionRFT,
+        targetAddress,
         {ReFungible: {const_data: [], pieces: 100}},
       ))).to.not.be.rejected;
 
@@ -181,7 +181,7 @@
 
       // Create a nested token
       await expect(executeTransaction(api, alice, api.tx.unique.createItem(
-        collectionRFT, 
+        collectionRFT,
         targetAddress,
         {ReFungible: {const_data: [], pieces: 100}},
       ))).to.not.be.rejected;
@@ -207,17 +207,29 @@
       await setCollectionPermissionsExceptSuccess(alice, collection, {nesting: 'Owner'});
       const targetToken = await createItemExpectSuccess(alice, collection, 'NFT');
 
+      const maxNestingLevel = 5;
+      let prevToken = targetToken;
+
       // Create a nested-token matryoshka
-      const nestedToken1 = await createItemExpectSuccess(alice, collection, 'NFT', {Ethereum: tokenIdToAddress(collection, targetToken)});
-      const nestedToken2 = await createItemExpectSuccess(alice, collection, 'NFT', {Ethereum: tokenIdToAddress(collection, nestedToken1)});
-      // The nesting depth is limited by 2
+      for (let i = 0; i < maxNestingLevel; i++) {
+        const nestedToken = await createItemExpectSuccess(
+          alice,
+          collection,
+          'NFT',
+          {Ethereum: tokenIdToAddress(collection, prevToken)},
+        );
+
+        prevToken = nestedToken;
+      }
+
+      // The nesting depth is limited by `maxNestingLevel`
       await expect(executeTransaction(api, alice, api.tx.unique.createItem(
-        collection, 
-        {Ethereum: tokenIdToAddress(collection, nestedToken2)}, 
+        collection,
+        {Ethereum: tokenIdToAddress(collection, prevToken)},
           {nft: {const_data: [], variable_data: []}} as any,
       )), 'while creating nested token').to.be.rejectedWith(/^structure\.DepthLimit$/);
 
-      expect(await getTopmostTokenOwner(api, collection, nestedToken2)).to.be.deep.equal({Substrate: alice.address});
+      expect(await getTopmostTokenOwner(api, collection, prevToken)).to.be.deep.equal({Substrate: alice.address});
     });
   });
 
@@ -231,8 +243,8 @@
 
       // Try to create a nested token
       await expect(executeTransaction(api, alice, api.tx.unique.createItem(
-        collection, 
-        {Ethereum: tokenIdToAddress(collection, targetToken)}, 
+        collection,
+        {Ethereum: tokenIdToAddress(collection, targetToken)},
           {nft: {const_data: [], variable_data: []}} as any,
       )), 'while creating nested token').to.be.rejectedWith(/^common\.NestingIsDisabled$/);
 
@@ -259,8 +271,8 @@
 
       // Try to create a nested token in the wrong collection
       await expect(executeTransaction(api, alice, api.tx.unique.createItem(
-        collection, 
-        {Ethereum: tokenIdToAddress(collection, targetToken)}, 
+        collection,
+        {Ethereum: tokenIdToAddress(collection, targetToken)},
           {nft: {const_data: [], variable_data: []}} as any,
       )), 'while creating nested token').to.be.rejectedWith(/common\.OnlyOwnerAllowedToNest/);
 
@@ -285,8 +297,8 @@
 
       // Try to create a nested token in the wrong collection
       await expect(executeTransaction(api, alice, api.tx.unique.createItem(
-        collection, 
-        {Ethereum: tokenIdToAddress(collection, targetToken)}, 
+        collection,
+        {Ethereum: tokenIdToAddress(collection, targetToken)},
           {nft: {const_data: [], variable_data: []}} as any,
       )), 'while creating nested token').to.be.rejectedWith(/common\.OnlyOwnerAllowedToNest/);
 
@@ -307,8 +319,8 @@
 
       // Try to create a nested token in the wrong collection
       await expect(executeTransaction(api, alice, api.tx.unique.createItem(
-        collection, 
-        {Ethereum: tokenIdToAddress(collection, targetToken)}, 
+        collection,
+        {Ethereum: tokenIdToAddress(collection, targetToken)},
           {nft: {const_data: [], variable_data: []}} as any,
       )), 'while creating nested token').to.be.rejectedWith(/common\.SourceCollectionIsNotAllowedToNest/);
 
@@ -332,11 +344,11 @@
 
       // Try to create a nested token
       await expect(executeTransaction(api, alice, api.tx.unique.createItem(
-        collectionFT, 
-        targetAddress, 
+        collectionFT,
+        targetAddress,
         {Fungible: {Value: 10}},
       )), 'while creating nested token').to.be.rejectedWith(/^common\.NestingIsDisabled$/);
-      
+
       // Create a token to be nested
       const newToken = await createItemExpectSuccess(alice, collectionFT, 'Fungible');
       // Try to nest
@@ -366,8 +378,8 @@
 
       // Try to create a nested token in the wrong collection
       await expect(executeTransaction(api, alice, api.tx.unique.createItem(
-        collectionFT, 
-        targetAddress, 
+        collectionFT,
+        targetAddress,
         {Fungible: {Value: 10}},
       )), 'while creating nested token').to.be.rejectedWith(/common\.OnlyOwnerAllowedToNest/);
 
@@ -393,8 +405,8 @@
 
       // Try to create a nested token in the wrong collection
       await expect(executeTransaction(api, alice, api.tx.unique.createItem(
-        collectionFT, 
-        targetAddress, 
+        collectionFT,
+        targetAddress,
         {Fungible: {Value: 10}},
       )), 'while creating nested token').to.be.rejectedWith(/common\.OnlyOwnerAllowedToNest/);
 
@@ -417,8 +429,8 @@
 
       // Try to create a nested token in the wrong collection
       await expect(executeTransaction(api, alice, api.tx.unique.createItem(
-        collectionFT, 
-        targetAddress, 
+        collectionFT,
+        targetAddress,
         {Fungible: {Value: 10}},
       )), 'while creating a nested token').to.be.rejectedWith(/common\.SourceCollectionIsNotAllowedToNest/);
 
@@ -441,8 +453,8 @@
 
       // Create a nested token
       await expect(executeTransaction(api, alice, api.tx.unique.createItem(
-        collectionRFT, 
-        targetAddress, 
+        collectionRFT,
+        targetAddress,
         {ReFungible: {const_data: [], pieces: 100}},
       )), 'while creating a nested token').to.be.rejectedWith(/^common\.NestingIsDisabled$/);
 
@@ -477,8 +489,8 @@
 
       // Try to create a nested token in the wrong collection
       await expect(executeTransaction(api, alice, api.tx.unique.createItem(
-        collectionRFT, 
-        targetAddress, 
+        collectionRFT,
+        targetAddress,
         {ReFungible: {const_data: [], pieces: 100}},
       )), 'while creating a nested token').to.be.rejectedWith(/common\.OnlyOwnerAllowedToNest/);
 
@@ -504,8 +516,8 @@
 
       // Try to create a nested token in the wrong collection
       await expect(executeTransaction(api, alice, api.tx.unique.createItem(
-        collectionRFT, 
-        targetAddress, 
+        collectionRFT,
+        targetAddress,
         {ReFungible: {const_data: [], pieces: 100}},
       )), 'while creating a nested token').to.be.rejectedWith(/common\.OnlyOwnerAllowedToNest/);
 
@@ -528,8 +540,8 @@
 
       // Try to create a nested token in the wrong collection
       await expect(executeTransaction(api, alice, api.tx.unique.createItem(
-        collectionRFT, 
-        targetAddress, 
+        collectionRFT,
+        targetAddress,
         {ReFungible: {const_data: [], pieces: 100}},
       )), 'while creating a nested token').to.be.rejectedWith(/common\.SourceCollectionIsNotAllowedToNest/);