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Vectorizedahbanavi
Vectorized
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ahbanavi
authored
Added burn functionality (chiru-labs#61)
* Added burn functionality. * Changed _initOneIndexed * Moved burn function into ERC721ABurnable * Moved burn function into ERC721ABurnable * Remove redundant burn check in ownershipOf * Optimized ownershipOf * Removed aux from AddressData for future PR * Packed currentIndex and totalBurned for gas savings * Added gas optimizations * Added gas optimizations * Added requested changes * Edited comments. * Renamed totalBurned to burnedCounter * Renamed to burnCounter * Updated comments. * Mark transferFrom/safeTransferFrom virtual * Mark transferFrom/safeTransferFrom virtual * Updated comments. * Tidy up tests * Inlined _exists for _burn and _transfer. * Merged custom errors * Merged custom errors * Fixed missing change from chiru-labs#59 * Gas optimization * update specs for _beforeTokenTransfers and _afterTokenTransfers hooks * Added chiru-labs#84 * Added chiru-labs#87 * Added chiru-labs#85 * Added chiru-labs#89 * Added comments on packing _currentIndex and _burnCounter * Removed overflow check for updatedIndex * Added requested test changes * Removed unused variable in burn test * Removed unused variable in burn test Co-authored-by: Amirhossein Banavi <ahbanavi@gmail.com>
1 parent d886d4d commit fb22621

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-36
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‎README.md

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@@ -54,7 +54,6 @@ contract Azuki is ERC721A {
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## Roadmap
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- [] Add burn function
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- [] Add flexibility for the first token id to not start at 0
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- [] Support ERC721 Upgradeable
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- [] Add more documentation on benefits of using ERC721A

‎contracts/ERC721A.sol

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‎contracts/extensions/ERC721ABurnable.sol

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// SPDX-License-Identifier: MIT
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// Creator: Chiru Labs
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pragma solidity ^0.8.4;
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import '../ERC721A.sol';
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import '@openzeppelin/contracts/utils/Context.sol';
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/**
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* @title ERC721A Burnable Token
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* @dev ERC721A Token that can be irreversibly burned (destroyed).
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*/
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abstract contract ERC721ABurnable is Context, ERC721A {
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/**
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* @dev Burns `tokenId`. See {ERC721A-_burn}.
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*
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* Requirements:
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*
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* - The caller must own `tokenId` or be an approved operator.
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*/
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function burn(uint256 tokenId) public virtual {
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TokenOwnership memory prevOwnership = ownershipOf(tokenId);
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bool isApprovedOrOwner = (_msgSender() == prevOwnership.addr ||
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isApprovedForAll(prevOwnership.addr, _msgSender()) ||
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getApproved(tokenId) == _msgSender());
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if (!isApprovedOrOwner) revert TransferCallerNotOwnerNorApproved();
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_burn(tokenId);
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}
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}

‎contracts/extensions/ERC721AOwnersExplicit.sol

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@@ -32,7 +32,7 @@ abstract contract ERC721AOwnersExplicit is ERC721A {
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}
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for (uint256 i = _nextOwnerToExplicitlySet; i <= endIndex; i++) {
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if (_ownerships[i].addr == address(0)) {
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if (_ownerships[i].addr == address(0) && !_ownerships[i].burned) {
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TokenOwnership memory ownership = ownershipOf(i);
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_ownerships[i].addr = ownership.addr;
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_ownerships[i].startTimestamp = ownership.startTimestamp;

‎contracts/mocks/ERC721ABurnableMock.sol

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// SPDX-License-Identifier: MIT
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// Creators: Chiru Labs
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pragma solidity ^0.8.4;
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import '../extensions/ERC721ABurnable.sol';
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contract ERC721ABurnableMock is ERC721A, ERC721ABurnable {
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constructor(string memory name_, string memory symbol_) ERC721A(name_, symbol_) {}
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function exists(uint256 tokenId) public view returns (bool) {
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return _exists(tokenId);
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}
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function safeMint(address to, uint256 quantity) public {
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_safeMint(to, quantity);
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}
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function getOwnershipAt(uint256 index) public view returns (TokenOwnership memory) {
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return _ownerships[index];
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}
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}

‎contracts/mocks/ERC721ABurnableOwnersExplicitMock.sol

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// SPDX-License-Identifier: MIT
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// Creators: Chiru Labs
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pragma solidity ^0.8.4;
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import '../extensions/ERC721ABurnable.sol';
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import '../extensions/ERC721AOwnersExplicit.sol';
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contract ERC721ABurnableOwnersExplicitMock is ERC721A, ERC721ABurnable, ERC721AOwnersExplicit {
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constructor(string memory name_, string memory symbol_) ERC721A(name_, symbol_) {}
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function exists(uint256 tokenId) public view returns (bool) {
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return _exists(tokenId);
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}
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function safeMint(address to, uint256 quantity) public {
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_safeMint(to, quantity);
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}
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function setOwnersExplicit(uint256 quantity) public {
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_setOwnersExplicit(quantity);
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}
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function getOwnershipAt(uint256 index) public view returns (TokenOwnership memory) {
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return _ownerships[index];
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}
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}

‎package-lock.json

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‎test/extensions/ERC721ABurnable.test.js

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const { expect } = require('chai');
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describe('ERC721ABurnable', function () {
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beforeEach(async function () {
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this.ERC721ABurnable = await ethers.getContractFactory('ERC721ABurnableMock');
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this.token = await this.ERC721ABurnable.deploy('Azuki', 'AZUKI');
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await this.token.deployed();
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});
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beforeEach(async function () {
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const [owner, addr1, addr2] = await ethers.getSigners();
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this.owner = owner;
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this.addr1 = addr1;
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this.addr2 = addr2;
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this.numTestTokens = 10;
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this.burnedTokenId = 5;
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await this.token['safeMint(address,uint256)'](this.addr1.address, this.numTestTokens);
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await this.token.connect(this.addr1).burn(this.burnedTokenId);
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});
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it('changes exists', async function () {
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expect(await this.token.exists(this.burnedTokenId)).to.be.false;
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});
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it('cannot burn a non-existing token', async function () {
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const query = this.token.connect(this.addr1).burn(this.numTestTokens);
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await expect(query).to.be.revertedWith(
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'OwnerQueryForNonexistentToken'
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);
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});
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it('cannot burn a burned token', async function () {
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const query = this.token.connect(this.addr1).burn(this.burnedTokenId);
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await expect(query).to.be.revertedWith(
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'OwnerQueryForNonexistentToken'
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);
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})
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it('cannot transfer a burned token', async function () {
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const query = this.token.connect(this.addr1)
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.transferFrom(this.addr1.address, this.addr2.address, this.burnedTokenId);
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await expect(query).to.be.revertedWith(
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'OwnerQueryForNonexistentToken'
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);
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})
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it('reduces totalSupply', async function () {
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const supplyBefore = await this.token.totalSupply();
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for (let i = 0; i < 2; ++i) {
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await this.token.connect(this.addr1).burn(i);
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expect(supplyBefore - (await this.token.totalSupply())).to.equal(i + 1);
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}
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})
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it('adjusts owners tokens by index', async function () {
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const n = await this.token.totalSupply();
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for (let i = 0; i < this.burnedTokenId; ++i) {
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expect(await this.token.tokenByIndex(i)).to.be.equal(i);
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}
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for (let i = this.burnedTokenId; i < n; ++i) {
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expect(await this.token.tokenByIndex(i)).to.be.equal(i + 1);
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}
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// tokenIds of addr1: [0,1,2,3,4,6,7,8,9]
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expect(await this.token.tokenOfOwnerByIndex(this.addr1.address, 2))
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.to.be.equal(2);
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await this.token.connect(this.addr1).burn(2);
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// tokenIds of addr1: [0,1,3,4,6,7,8,9]
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expect(await this.token.tokenOfOwnerByIndex(this.addr1.address, 2))
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.to.be.equal(3);
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await this.token.connect(this.addr1).burn(0);
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// tokenIds of addr1: [1,3,4,6,7,8,9]
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expect(await this.token.tokenOfOwnerByIndex(this.addr1.address, 2))
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.to.be.equal(4);
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await this.token.connect(this.addr1).burn(3);
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// tokenIds of addr1: [1,4,6,7,8,9]
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expect(await this.token.tokenOfOwnerByIndex(this.addr1.address, 2))
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.to.be.equal(6);
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})
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it('adjusts owners balances', async function () {
82+
expect(await this.token.balanceOf(this.addr1.address))
83+
.to.be.equal(this.numTestTokens - 1);
84+
});
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it('adjusts token by index', async function () {
87+
const n = await this.token.totalSupply();
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for (let i = 0; i < this.burnedTokenId; ++i) {
89+
expect(await this.token.tokenByIndex(i)).to.be.equal(i);
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}
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for (let i = this.burnedTokenId; i < n; ++i) {
92+
expect(await this.token.tokenByIndex(i)).to.be.equal(i + 1);
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}
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await expect(this.token.tokenByIndex(n)).to.be.revertedWith(
95+
'TokenIndexOutOfBounds'
96+
);
97+
});
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99+
describe('ownerships correctly set', async function () {
100+
it('with token before previously burnt token transfered and burned', async function () {
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const tokenIdToBurn = this.burnedTokenId - 1;
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await this.token.connect(this.addr1)
103+
.transferFrom(this.addr1.address, this.addr2.address, tokenIdToBurn);
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expect(await this.token.ownerOf(tokenIdToBurn)).to.be.equal(this.addr2.address);
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await this.token.connect(this.addr2).burn(tokenIdToBurn);
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for (let i = 0; i < this.numTestTokens; ++i) {
107+
if (i == tokenIdToBurn || i == this.burnedTokenId) {
108+
await expect(this.token.ownerOf(i)).to.be.revertedWith(
109+
'OwnerQueryForNonexistentToken'
110+
);
111+
} else {
112+
expect(await this.token.ownerOf(i)).to.be.equal(this.addr1.address);
113+
}
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}
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});
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117+
it('with token after previously burnt token transfered and burned', async function () {
118+
const tokenIdToBurn = this.burnedTokenId + 1;
119+
await this.token.connect(this.addr1)
120+
.transferFrom(this.addr1.address, this.addr2.address, tokenIdToBurn);
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expect(await this.token.ownerOf(tokenIdToBurn)).to.be.equal(this.addr2.address);
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await this.token.connect(this.addr2).burn(tokenIdToBurn);
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for (let i = 0; i < this.numTestTokens; ++i) {
124+
if (i == tokenIdToBurn || i == this.burnedTokenId) {
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await expect(this.token.ownerOf(i)).to.be.revertedWith(
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'OwnerQueryForNonexistentToken'
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)
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} else {
129+
expect(await this.token.ownerOf(i)).to.be.equal(this.addr1.address);
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}
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}
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});
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it('with first token burned', async function () {
135+
await this.token.connect(this.addr1).burn(0);
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for (let i = 0; i < this.numTestTokens; ++i) {
137+
if (i == 0 || i == this.burnedTokenId) {
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await expect(this.token.ownerOf(i)).to.be.revertedWith(
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'OwnerQueryForNonexistentToken'
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)
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} else {
142+
expect(await this.token.ownerOf(i)).to.be.equal(this.addr1.address);
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}
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}
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});
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it('with last token burned', async function () {
148+
await expect(this.token.ownerOf(this.numTestTokens)).to.be.revertedWith(
149+
'OwnerQueryForNonexistentToken'
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)
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await this.token.connect(this.addr1).burn(this.numTestTokens - 1);
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await expect(this.token.ownerOf(this.numTestTokens - 1)).to.be.revertedWith(
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'OwnerQueryForNonexistentToken'
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)
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});
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});
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});

‎test/extensions/ERC721ABurnableOwnersExplicit.test.js

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const { expect } = require('chai');
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const { constants } = require('@openzeppelin/test-helpers');
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const { ZERO_ADDRESS } = constants;
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describe('ERC721ABurnableOwnersExplicit', function () {
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beforeEach(async function () {
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this.ERC721ABurnableOwnersExplicit = await ethers.getContractFactory('ERC721ABurnableOwnersExplicitMock');
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this.token = await this.ERC721ABurnableOwnersExplicit.deploy('Azuki', 'AZUKI');
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await this.token.deployed();
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});
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beforeEach(async function () {
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const [owner, addr1, addr2, addr3] = await ethers.getSigners();
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this.owner = owner;
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this.addr1 = addr1;
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this.addr2 = addr2;
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this.addr3 = addr3;
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await this.token['safeMint(address,uint256)'](addr1.address, 1);
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await this.token['safeMint(address,uint256)'](addr2.address, 2);
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await this.token['safeMint(address,uint256)'](addr3.address, 3);
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await this.token.connect(this.addr1).burn(0);
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await this.token.connect(this.addr3).burn(4);
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await this.token.setOwnersExplicit(6);
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});
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it('ownerships correctly set', async function () {
27+
for (let tokenId = 0; tokenId < 6; tokenId++) {
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let owner = await this.token.getOwnershipAt(tokenId);
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expect(owner[0]).to.not.equal(ZERO_ADDRESS);
30+
if (tokenId == 0 || tokenId == 4) {
31+
expect(owner[2]).to.equal(true);
32+
await expect(this.token.ownerOf(tokenId)).to.be.revertedWith(
33+
'OwnerQueryForNonexistentToken'
34+
)
35+
} else {
36+
expect(owner[2]).to.equal(false);
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if (tokenId < 1+2) {
38+
expect(await this.token.ownerOf(tokenId)).to.be.equal(this.addr2.address);
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} else {
40+
expect(await this.token.ownerOf(tokenId)).to.be.equal(this.addr3.address);
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}
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}
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}
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});
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});

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