difftreelog
feat prevent ouroboros creation during nest
in: master
11 files changed
client/rpc/src/lib.rsdiffbeforeafterboth--- a/client/rpc/src/lib.rs
+++ b/client/rpc/src/lib.rs
@@ -77,11 +77,7 @@
) -> Result<Vec<u8>>;
#[rpc(name = "unique_totalSupply")]
- fn total_supply(
- &self,
- collection: CollectionId,
- at: Option<BlockHash>,
- ) -> Result<u32>;
+ fn total_supply(&self, collection: CollectionId, at: Option<BlockHash>) -> Result<u32>;
#[rpc(name = "unique_accountBalance")]
fn account_balance(
&self,
pallets/common/src/lib.rsdiffbeforeafterboth--- a/pallets/common/src/lib.rs
+++ b/pallets/common/src/lib.rs
@@ -918,7 +918,7 @@
fn check_nesting(
&self,
sender: T::CrossAccountId,
- from: CollectionId,
+ from: (CollectionId, TokenId),
under: TokenId,
budget: &dyn Budget,
) -> DispatchResult;
pallets/fungible/src/common.rsdiffbeforeafterboth--- a/pallets/fungible/src/common.rs
+++ b/pallets/fungible/src/common.rs
@@ -237,7 +237,7 @@
fn check_nesting(
&self,
_sender: <T>::CrossAccountId,
- _from: CollectionId,
+ _from: (CollectionId, TokenId),
_under: TokenId,
_budget: &dyn Budget,
) -> sp_runtime::DispatchResult {
pallets/fungible/src/lib.rsdiffbeforeafterboth--- a/pallets/fungible/src/lib.rs
+++ b/pallets/fungible/src/lib.rs
@@ -224,7 +224,12 @@
let dispatch = T::CollectionDispatch::dispatch(handle);
let dispatch = dispatch.as_dyn();
- dispatch.check_nesting(from.clone(), collection.id, target.1, nesting_budget)?;
+ dispatch.check_nesting(
+ from.clone(),
+ (collection.id, TokenId::default()),
+ target.1,
+ nesting_budget,
+ )?;
}
// =========
@@ -293,7 +298,12 @@
let dispatch = T::CollectionDispatch::dispatch(handle);
let dispatch = dispatch.as_dyn();
- dispatch.check_nesting(sender.clone(), collection.id, target.1, nesting_budget)?;
+ dispatch.check_nesting(
+ sender.clone(),
+ (collection.id, TokenId::default()),
+ target.1,
+ nesting_budget,
+ )?;
}
}
@@ -386,10 +396,11 @@
if let Some(source) = T::CrossTokenAddressMapping::address_to_token(from) {
// TODO: should collection owner be allowed to perform this transfer?
ensure!(
- <PalletStructure<T>>::indirectly_owned(
+ <PalletStructure<T>>::check_indirectly_owned(
spender.clone(),
source.0,
source.1,
+ None,
nesting_budget
)?,
<CommonError<T>>::ApprovedValueTooLow,
pallets/nonfungible/src/common.rsdiffbeforeafterboth--- a/pallets/nonfungible/src/common.rs
+++ b/pallets/nonfungible/src/common.rs
@@ -251,7 +251,7 @@
fn check_nesting(
&self,
sender: T::CrossAccountId,
- from: CollectionId,
+ from: (CollectionId, TokenId),
under: TokenId,
budget: &dyn Budget,
) -> sp_runtime::DispatchResult {
pallets/nonfungible/src/lib.rsdiffbeforeafterboth--- a/pallets/nonfungible/src/lib.rs
+++ b/pallets/nonfungible/src/lib.rs
@@ -296,7 +296,12 @@
let dispatch = T::CollectionDispatch::dispatch(handle);
let dispatch = dispatch.as_dyn();
- dispatch.check_nesting(from.clone(), collection.id, target.1, nesting_budget)?;
+ dispatch.check_nesting(
+ from.clone(),
+ (collection.id, token),
+ target.1,
+ nesting_budget,
+ )?;
}
// =========
@@ -381,13 +386,18 @@
);
}
- for (to, _) in balances.iter() {
- if let Some(target) = T::CrossTokenAddressMapping::address_to_token(to) {
+ 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, target.1, nesting_budget)?;
+ dispatch.check_nesting(
+ sender.clone(),
+ (collection.id, token),
+ target.1,
+ nesting_budget,
+ )?;
}
}
@@ -535,10 +545,11 @@
if let Some(source) = T::CrossTokenAddressMapping::address_to_token(from) {
// TODO: should collection owner be allowed to perform this transfer?
ensure!(
- <PalletStructure<T>>::indirectly_owned(
+ <PalletStructure<T>>::check_indirectly_owned(
spender.clone(),
source.0,
source.1,
+ None,
nesting_budget
)?,
<CommonError<T>>::ApprovedValueTooLow,
@@ -610,31 +621,40 @@
pub fn check_nesting(
handle: &NonfungibleHandle<T>,
sender: T::CrossAccountId,
- from: CollectionId,
+ from: (CollectionId, TokenId),
under: TokenId,
nesting_budget: &dyn Budget,
) -> DispatchResult {
fn ensure_sender_allowed<T: Config>(
collection: CollectionId,
token: TokenId,
+ for_nest: (CollectionId, TokenId),
sender: T::CrossAccountId,
budget: &dyn Budget,
) -> DispatchResult {
ensure!(
- <PalletStructure<T>>::indirectly_owned(sender, collection, token, budget)?,
+ <PalletStructure<T>>::check_indirectly_owned(
+ sender,
+ collection,
+ token,
+ Some(for_nest),
+ budget
+ )?,
<CommonError<T>>::OnlyOwnerAllowedToNest,
);
Ok(())
}
match handle.limits.nesting_rule() {
NestingRule::Disabled => fail!(<CommonError<T>>::NestingIsDisabled),
- NestingRule::Owner => ensure_sender_allowed::<T>(handle.id, under, sender, nesting_budget)?,
+ NestingRule::Owner => {
+ ensure_sender_allowed::<T>(handle.id, under, from, sender, nesting_budget)?
+ }
NestingRule::OwnerRestricted(whitelist) => {
ensure!(
- whitelist.contains(&from),
+ whitelist.contains(&from.0),
<CommonError<T>>::SourceCollectionIsNotAllowedToNest
);
- ensure_sender_allowed::<T>(handle.id, under, sender, nesting_budget)?
+ ensure_sender_allowed::<T>(handle.id, under, from, sender, nesting_budget)?
}
}
Ok(())
pallets/refungible/src/common.rsdiffbeforeafterboth1// 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/>.1617use core::marker::PhantomData;1819use sp_std::collections::btree_map::BTreeMap;20use frame_support::{dispatch::DispatchResultWithPostInfo, fail, weights::Weight, BoundedVec};21use up_data_structs::{22 CollectionId, TokenId, CustomDataLimit, CreateItemExData, CreateRefungibleExData,23 budget::Budget,24};25use pallet_common::{CommonCollectionOperations, CommonWeightInfo, with_weight};26use sp_runtime::DispatchError;27use sp_std::{vec::Vec, vec};2829use crate::{30 AccountBalance, Allowance, Balance, Config, Error, Owned, Pallet, RefungibleHandle,31 SelfWeightOf, TokenData, weights::WeightInfo, TokensMinted,32};3334macro_rules! max_weight_of {35 ($($method:ident ($($args:tt)*)),*) => {36 037 $(38 .max(<SelfWeightOf<T>>::$method($($args)*))39 )*40 };41}4243pub struct CommonWeights<T: Config>(PhantomData<T>);44impl<T: Config> CommonWeightInfo<T::CrossAccountId> for CommonWeights<T> {45 fn create_item() -> Weight {46 <SelfWeightOf<T>>::create_item()47 }4849 fn create_multiple_items(amount: u32) -> Weight {50 <SelfWeightOf<T>>::create_multiple_items(amount)51 }5253 fn create_multiple_items_ex(call: &CreateItemExData<T::CrossAccountId>) -> Weight {54 match call {55 CreateItemExData::RefungibleMultipleOwners(i) => {56 <SelfWeightOf<T>>::create_multiple_items_ex_multiple_owners(i.users.len() as u32)57 }58 CreateItemExData::RefungibleMultipleItems(i) => {59 <SelfWeightOf<T>>::create_multiple_items_ex_multiple_items(i.len() as u32)60 }61 _ => 0,62 }63 }6465 fn burn_item() -> Weight {66 max_weight_of!(burn_item_partial(), burn_item_fully())67 }6869 fn transfer() -> Weight {70 max_weight_of!(71 transfer_normal(),72 transfer_creating(),73 transfer_removing(),74 transfer_creating_removing()75 )76 }7778 fn approve() -> Weight {79 <SelfWeightOf<T>>::approve()80 }8182 fn transfer_from() -> Weight {83 max_weight_of!(84 transfer_from_normal(),85 transfer_from_creating(),86 transfer_from_removing(),87 transfer_from_creating_removing()88 )89 }9091 fn burn_from() -> Weight {92 <SelfWeightOf<T>>::burn_from()93 }9495 fn set_variable_metadata(bytes: u32) -> Weight {96 <SelfWeightOf<T>>::set_variable_metadata(bytes)97 }98}99100fn map_create_data<T: Config>(101 data: up_data_structs::CreateItemData,102 to: &T::CrossAccountId,103) -> Result<CreateRefungibleExData<T::CrossAccountId>, DispatchError> {104 match data {105 up_data_structs::CreateItemData::ReFungible(data) => Ok(CreateRefungibleExData {106 const_data: data.const_data,107 variable_data: data.variable_data,108 users: {109 let mut out = BTreeMap::new();110 out.insert(to.clone(), data.pieces);111 out.try_into().expect("limit > 0")112 },113 }),114 _ => fail!(<Error<T>>::NotRefungibleDataUsedToMintFungibleCollectionToken),115 }116}117118impl<T: Config> CommonCollectionOperations<T> for RefungibleHandle<T> {119 fn create_item(120 &self,121 sender: T::CrossAccountId,122 to: T::CrossAccountId,123 data: up_data_structs::CreateItemData,124 nesting_budget: &dyn Budget,125 ) -> DispatchResultWithPostInfo {126 with_weight(127 <Pallet<T>>::create_item(128 self,129 &sender,130 map_create_data::<T>(data, &to)?,131 nesting_budget,132 ),133 <CommonWeights<T>>::create_item(),134 )135 }136137 fn create_multiple_items(138 &self,139 sender: T::CrossAccountId,140 to: T::CrossAccountId,141 data: Vec<up_data_structs::CreateItemData>,142 nesting_budget: &dyn Budget,143 ) -> DispatchResultWithPostInfo {144 let data = data145 .into_iter()146 .map(|d| map_create_data::<T>(d, &to))147 .collect::<Result<Vec<_>, DispatchError>>()?;148149 let amount = data.len();150 with_weight(151 <Pallet<T>>::create_multiple_items(self, &sender, data, nesting_budget),152 <CommonWeights<T>>::create_multiple_items(amount as u32),153 )154 }155156 fn create_multiple_items_ex(157 &self,158 sender: <T>::CrossAccountId,159 data: CreateItemExData<T::CrossAccountId>,160 nesting_budget: &dyn Budget,161 ) -> DispatchResultWithPostInfo {162 let weight = <CommonWeights<T>>::create_multiple_items_ex(&data);163 let data = match data {164 CreateItemExData::RefungibleMultipleOwners(r) => vec![r],165 CreateItemExData::RefungibleMultipleItems(r)166 if r.iter().all(|i| i.users.len() == 1) =>167 {168 r.into_inner()169 }170 _ => fail!(<Error<T>>::NotRefungibleDataUsedToMintFungibleCollectionToken),171 };172173 with_weight(174 <Pallet<T>>::create_multiple_items(self, &sender, data, nesting_budget),175 weight,176 )177 }178179 fn burn_item(180 &self,181 sender: T::CrossAccountId,182 token: TokenId,183 amount: u128,184 ) -> DispatchResultWithPostInfo {185 with_weight(186 <Pallet<T>>::burn(self, &sender, token, amount),187 <CommonWeights<T>>::burn_item(),188 )189 }190191 fn transfer(192 &self,193 from: T::CrossAccountId,194 to: T::CrossAccountId,195 token: TokenId,196 amount: u128,197 nesting_budget: &dyn Budget,198 ) -> DispatchResultWithPostInfo {199 with_weight(200 <Pallet<T>>::transfer(self, &from, &to, token, amount, nesting_budget),201 <CommonWeights<T>>::transfer(),202 )203 }204205 fn approve(206 &self,207 sender: T::CrossAccountId,208 spender: T::CrossAccountId,209 token: TokenId,210 amount: u128,211 ) -> DispatchResultWithPostInfo {212 with_weight(213 <Pallet<T>>::set_allowance(self, &sender, &spender, token, amount),214 <CommonWeights<T>>::approve(),215 )216 }217218 fn transfer_from(219 &self,220 sender: T::CrossAccountId,221 from: T::CrossAccountId,222 to: T::CrossAccountId,223 token: TokenId,224 amount: u128,225 nesting_budget: &dyn Budget,226 ) -> DispatchResultWithPostInfo {227 with_weight(228 <Pallet<T>>::transfer_from(self, &sender, &from, &to, token, amount, nesting_budget),229 <CommonWeights<T>>::transfer_from(),230 )231 }232233 fn burn_from(234 &self,235 sender: T::CrossAccountId,236 from: T::CrossAccountId,237 token: TokenId,238 amount: u128,239 nesting_budget: &dyn Budget,240 ) -> DispatchResultWithPostInfo {241 with_weight(242 <Pallet<T>>::burn_from(self, &sender, &from, token, amount, nesting_budget),243 <CommonWeights<T>>::burn_from(),244 )245 }246247 fn set_variable_metadata(248 &self,249 sender: T::CrossAccountId,250 token: TokenId,251 data: BoundedVec<u8, CustomDataLimit>,252 ) -> DispatchResultWithPostInfo {253 let len = data.len();254 with_weight(255 <Pallet<T>>::set_variable_metadata(self, &sender, token, data),256 <CommonWeights<T>>::set_variable_metadata(len as u32),257 )258 }259260 fn check_nesting(261 &self,262 _sender: <T>::CrossAccountId,263 _from: CollectionId,264 _under: TokenId,265 _budget: &dyn Budget,266 ) -> sp_runtime::DispatchResult {267 fail!(<Error<T>>::RefungibleDisallowsNesting)268 }269270 fn account_tokens(&self, account: T::CrossAccountId) -> Vec<TokenId> {271 <Owned<T>>::iter_prefix((self.id, account))272 .map(|(id, _)| id)273 .collect()274 }275276 fn collection_tokens(&self) -> Vec<TokenId> {277 <TokenData<T>>::iter_prefix((self.id,))278 .map(|(id, _)| id)279 .collect()280 }281282 fn token_exists(&self, token: TokenId) -> bool {283 <Pallet<T>>::token_exists(self, token)284 }285286 fn last_token_id(&self) -> TokenId {287 TokenId(<TokensMinted<T>>::get(self.id))288 }289290 fn token_owner(&self, _token: TokenId) -> Option<T::CrossAccountId> {291 None292 }293 fn const_metadata(&self, token: TokenId) -> Vec<u8> {294 <TokenData<T>>::get((self.id, token))295 .const_data296 .into_inner()297 }298 fn variable_metadata(&self, token: TokenId) -> Vec<u8> {299 <TokenData<T>>::get((self.id, token))300 .variable_data301 .into_inner()302 }303304 fn total_supply(&self) -> u32 {305 <Pallet<T>>::total_supply(self)306 }307308 fn account_balance(&self, account: T::CrossAccountId) -> u32 {309 <AccountBalance<T>>::get((self.id, account))310 }311312 fn balance(&self, account: T::CrossAccountId, token: TokenId) -> u128 {313 <Balance<T>>::get((self.id, token, account))314 }315316 fn allowance(317 &self,318 sender: T::CrossAccountId,319 spender: T::CrossAccountId,320 token: TokenId,321 ) -> u128 {322 <Allowance<T>>::get((self.id, token, sender, spender))323 }324}pallets/refungible/src/lib.rsdiffbeforeafterboth--- a/pallets/refungible/src/lib.rs
+++ b/pallets/refungible/src/lib.rs
@@ -352,7 +352,12 @@
let dispatch = T::CollectionDispatch::dispatch(handle);
let dispatch = dispatch.as_dyn();
- dispatch.check_nesting(from.clone(), collection.id, target.1, nesting_budget)?;
+ dispatch.check_nesting(
+ from.clone(),
+ (collection.id, token),
+ target.1,
+ nesting_budget,
+ )?;
}
// =========
@@ -455,7 +460,8 @@
}
}
- for token in data.iter() {
+ 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)?;
@@ -464,7 +470,7 @@
dispatch.check_nesting(
sender.clone(),
- collection.id,
+ (collection.id, token_id),
target.1,
nesting_budget,
)?;
@@ -575,10 +581,11 @@
if let Some(source) = T::CrossTokenAddressMapping::address_to_token(from) {
// TODO: should collection owner be allowed to perform this transfer?
ensure!(
- <PalletStructure<T>>::indirectly_owned(
+ <PalletStructure<T>>::check_indirectly_owned(
spender.clone(),
source.0,
source.1,
+ None,
nesting_budget
)?,
<CommonError<T>>::ApprovedValueTooLow,
pallets/structure/src/lib.rsdiffbeforeafterboth--- a/pallets/structure/src/lib.rs
+++ b/pallets/structure/src/lib.rs
@@ -71,7 +71,7 @@
#[derive(PartialEq)]
pub enum Parent<CrossAccountId> {
/// Token owned by normal account
- Normal(CrossAccountId),
+ User(CrossAccountId),
/// Passed token not found
TokenNotFound,
/// Token owner is another token (target token still may not exist)
@@ -94,7 +94,7 @@
Ok(match handle.token_owner(token) {
Some(owner) => match T::CrossTokenAddressMapping::address_to_token(&owner) {
Some((collection, token)) => Parent::Token(collection, token),
- None => Parent::Normal(owner),
+ None => Parent::User(owner),
},
None => Parent::TokenNotFound,
})
@@ -137,29 +137,46 @@
) -> Result<T::CrossAccountId, DispatchError> {
let owner = Self::parent_chain(collection, token)
.take_while(|_| budget.consume())
- .find(|p| matches!(p, Ok(Parent::Normal(_) | Parent::TokenNotFound)))
+ .find(|p| matches!(p, Ok(Parent::User(_) | Parent::TokenNotFound)))
.ok_or(<Error<T>>::DepthLimit)??;
Ok(match owner {
- Parent::Normal(v) => v,
+ Parent::User(v) => v,
_ => fail!(<Error<T>>::TokenNotFound),
})
}
/// Check if token indirectly owned by specified user
- pub fn indirectly_owned(
+ pub fn check_indirectly_owned(
user: T::CrossAccountId,
collection: CollectionId,
token: TokenId,
+ for_nest: Option<(CollectionId, TokenId)>,
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::Normal(user),
+ None => Parent::User(user),
};
- Ok(Self::parent_chain(collection, token)
- .take_while(|_| budget.consume())
- .any(|parent| Ok(&target_parent) == parent.as_ref()))
+ // Tried to nest token in itself
+ if Some((collection, token)) == for_nest {
+ return Err(<Error<T>>::OuroborosDetected.into());
+ }
+
+ for parent in Self::parent_chain(collection, token).take_while(|_| budget.consume()) {
+ match parent? {
+ // Tried to nest token in chain, which has this token as one of parents
+ Parent::Token(collection, token) if Some((collection, token)) == for_nest => {
+ return Err(<Error<T>>::OuroborosDetected.into())
+ }
+ // Found needed parent, token is indirecty owned
+ v if v == target_parent => return Ok(true),
+ Parent::TokenNotFound => return Ok(false),
+ _ => {}
+ }
+ }
+
+ Err(<Error<T>>::DepthLimit.into())
}
}
tests/src/eth/util/helpers.tsdiffbeforeafterboth--- a/tests/src/eth/util/helpers.ts
+++ b/tests/src/eth/util/helpers.ts
@@ -23,7 +23,7 @@
import usingApi, {submitTransactionAsync} from '../../substrate/substrate-api';
import {IKeyringPair} from '@polkadot/types/types';
import {expect} from 'chai';
-import {getGenericResult, UNIQUE} from '../../util/helpers';
+import {CrossAccountId, getGenericResult, UNIQUE} from '../../util/helpers';
import * as solc from 'solc';
import config from '../../config';
import privateKey from '../../substrate/privateKey';
@@ -80,6 +80,11 @@
]);
return Web3.utils.toChecksumAddress('0x' + buf.toString('hex'));
}
+export function tokenIdToCross(collection: number, token: number): CrossAccountId {
+ return {
+ Ethereum: tokenIdToAddress(collection, token),
+ };
+}
export function createEthAccount(web3: Web3) {
const account = web3.eth.accounts.create();
tests/src/nesting/graphs.test.tsdiffbeforeafterboth--- /dev/null
+++ b/tests/src/nesting/graphs.test.ts
@@ -0,0 +1,51 @@
+import {ApiPromise} from '@polkadot/api';
+import {IKeyringPair} from '@polkadot/types/types';
+import {expect} from 'chai';
+import {tokenIdToCross} from '../eth/util/helpers';
+import privateKey from '../substrate/privateKey';
+import usingApi, {executeTransaction} from '../substrate/substrate-api';
+import {getCreateCollectionResult, transferExpectSuccess} from '../util/helpers';
+
+/**
+ * ```dot
+ * 4 -> 3 -> 2 -> 1
+ * 7 -> 6 -> 5 -> 2
+ * 8 -> 5
+ * ```
+ */
+async function buildComplexObjectGraph(api: ApiPromise, sender: IKeyringPair): Promise<number> {
+ const events = await executeTransaction(api, sender, api.tx.unique.createCollectionEx({mode: 'NFT'}));
+ const {collectionId} = getCreateCollectionResult(events);
+
+ await executeTransaction(api, sender, api.tx.unique.createMultipleItemsEx(collectionId, {NFT: Array(8).fill({owner: {Substrate: sender.address}})}));
+
+ await transferExpectSuccess(collectionId, 8, sender, tokenIdToCross(collectionId, 5));
+
+ await transferExpectSuccess(collectionId, 7, sender, tokenIdToCross(collectionId, 6));
+ await transferExpectSuccess(collectionId, 6, sender, tokenIdToCross(collectionId, 5));
+ await transferExpectSuccess(collectionId, 5, sender, tokenIdToCross(collectionId, 2));
+
+ await transferExpectSuccess(collectionId, 4, sender, tokenIdToCross(collectionId, 3));
+ await transferExpectSuccess(collectionId, 3, sender, tokenIdToCross(collectionId, 2));
+ await transferExpectSuccess(collectionId, 2, sender, tokenIdToCross(collectionId, 1));
+
+ return collectionId;
+}
+
+describe('graphs', () => {
+ it('ouroboros can\'t be created in graph', async () => {
+ await usingApi(async api => {
+ const alice = privateKey('//Alice');
+ const collection = await buildComplexObjectGraph(api, alice);
+
+ // to self
+ await expect(executeTransaction(api, alice, api.tx.unique.transfer(tokenIdToCross(collection, 1), collection, 1, 1)))
+ .to.be.rejectedWith(/structure\.OuroborosDetected/);
+ // to nested part of graph
+ await expect(executeTransaction(api, alice, api.tx.unique.transfer(tokenIdToCross(collection, 5), collection, 1, 1)))
+ .to.be.rejectedWith(/structure\.OuroborosDetected/);
+ await expect(executeTransaction(api, alice, api.tx.unique.transfer(tokenIdToCross(collection, 8), collection, 2, 1)))
+ .to.be.rejectedWith(/structure\.OuroborosDetected/);
+ });
+ });
+});