From fd22aea378aa9f044c142af1d93edd6f04d33cfd Mon Sep 17 00:00:00 2001 From: owen05 Date: Wed, 14 Apr 2021 23:06:10 +0800 Subject: [PATCH] update erc721 --- .../external/ERC721/ERC721Enumerable.sol | 160 ++++++++++++++++++ .../external/ERC721/ERC721URIStorage.sol | 4 +- contracts/intf/IERC721Enumerable.sol | 32 ++++ 3 files changed, 194 insertions(+), 2 deletions(-) create mode 100644 contracts/external/ERC721/ERC721Enumerable.sol create mode 100644 contracts/intf/IERC721Enumerable.sol diff --git a/contracts/external/ERC721/ERC721Enumerable.sol b/contracts/external/ERC721/ERC721Enumerable.sol new file mode 100644 index 0000000..6ffc270 --- /dev/null +++ b/contracts/external/ERC721/ERC721Enumerable.sol @@ -0,0 +1,160 @@ +// This is a file copied from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC721/extensions/ERC721Enumerable.sol +// SPDX-License-Identifier: MIT + +pragma solidity 0.6.9; + +import "./ERC721.sol"; +import "../../intf/IERC721Enumerable.sol"; + +/** + * @dev This implements an optional extension of {ERC721} defined in the EIP that adds + * enumerability of all the token ids in the contract as well as all token ids owned by each + * account. + */ +abstract contract ERC721Enumerable is ERC721, IERC721Enumerable { + // Mapping from owner to list of owned token IDs + mapping(address => mapping(uint256 => uint256)) private _ownedTokens; + + // Mapping from token ID to index of the owner tokens list + mapping(uint256 => uint256) private _ownedTokensIndex; + + // Array with all token ids, used for enumeration + uint256[] private _allTokens; + + // Mapping from token id to position in the allTokens array + mapping(uint256 => uint256) private _allTokensIndex; + + /** + * @dev See {IERC165-supportsInterface}. + */ + function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165, ERC721) returns (bool) { + return interfaceId == type(IERC721Enumerable).interfaceId + || super.supportsInterface(interfaceId); + } + + /** + * @dev See {IERC721Enumerable-tokenOfOwnerByIndex}. + */ + function tokenOfOwnerByIndex(address owner, uint256 index) public view virtual override returns (uint256) { + require(index < ERC721.balanceOf(owner), "ERC721Enumerable: owner index out of bounds"); + return _ownedTokens[owner][index]; + } + + /** + * @dev See {IERC721Enumerable-totalSupply}. + */ + function totalSupply() public view virtual override returns (uint256) { + return _allTokens.length; + } + + /** + * @dev See {IERC721Enumerable-tokenByIndex}. + */ + function tokenByIndex(uint256 index) public view virtual override returns (uint256) { + require(index < ERC721Enumerable.totalSupply(), "ERC721Enumerable: global index out of bounds"); + return _allTokens[index]; + } + + /** + * @dev Hook that is called before any token transfer. This includes minting + * and burning. + * + * Calling conditions: + * + * - When `from` and `to` are both non-zero, ``from``'s `tokenId` will be + * transferred to `to`. + * - When `from` is zero, `tokenId` will be minted for `to`. + * - When `to` is zero, ``from``'s `tokenId` will be burned. + * - `from` cannot be the zero address. + * - `to` cannot be the zero address. + * + * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks]. + */ + function _beforeTokenTransfer(address from, address to, uint256 tokenId) internal virtual override { + super._beforeTokenTransfer(from, to, tokenId); + + if (from == address(0)) { + _addTokenToAllTokensEnumeration(tokenId); + } else if (from != to) { + _removeTokenFromOwnerEnumeration(from, tokenId); + } + if (to == address(0)) { + _removeTokenFromAllTokensEnumeration(tokenId); + } else if (to != from) { + _addTokenToOwnerEnumeration(to, tokenId); + } + } + + /** + * @dev Private function to add a token to this extension's ownership-tracking data structures. + * @param to address representing the new owner of the given token ID + * @param tokenId uint256 ID of the token to be added to the tokens list of the given address + */ + function _addTokenToOwnerEnumeration(address to, uint256 tokenId) private { + uint256 length = ERC721.balanceOf(to); + _ownedTokens[to][length] = tokenId; + _ownedTokensIndex[tokenId] = length; + } + + /** + * @dev Private function to add a token to this extension's token tracking data structures. + * @param tokenId uint256 ID of the token to be added to the tokens list + */ + function _addTokenToAllTokensEnumeration(uint256 tokenId) private { + _allTokensIndex[tokenId] = _allTokens.length; + _allTokens.push(tokenId); + } + + /** + * @dev Private function to remove a token from this extension's ownership-tracking data structures. Note that + * while the token is not assigned a new owner, the `_ownedTokensIndex` mapping is _not_ updated: this allows for + * gas optimizations e.g. when performing a transfer operation (avoiding double writes). + * This has O(1) time complexity, but alters the order of the _ownedTokens array. + * @param from address representing the previous owner of the given token ID + * @param tokenId uint256 ID of the token to be removed from the tokens list of the given address + */ + function _removeTokenFromOwnerEnumeration(address from, uint256 tokenId) private { + // To prevent a gap in from's tokens array, we store the last token in the index of the token to delete, and + // then delete the last slot (swap and pop). + + uint256 lastTokenIndex = ERC721.balanceOf(from) - 1; + uint256 tokenIndex = _ownedTokensIndex[tokenId]; + + // When the token to delete is the last token, the swap operation is unnecessary + if (tokenIndex != lastTokenIndex) { + uint256 lastTokenId = _ownedTokens[from][lastTokenIndex]; + + _ownedTokens[from][tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token + _ownedTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index + } + + // This also deletes the contents at the last position of the array + delete _ownedTokensIndex[tokenId]; + delete _ownedTokens[from][lastTokenIndex]; + } + + /** + * @dev Private function to remove a token from this extension's token tracking data structures. + * This has O(1) time complexity, but alters the order of the _allTokens array. + * @param tokenId uint256 ID of the token to be removed from the tokens list + */ + function _removeTokenFromAllTokensEnumeration(uint256 tokenId) private { + // To prevent a gap in the tokens array, we store the last token in the index of the token to delete, and + // then delete the last slot (swap and pop). + + uint256 lastTokenIndex = _allTokens.length - 1; + uint256 tokenIndex = _allTokensIndex[tokenId]; + + // When the token to delete is the last token, the swap operation is unnecessary. However, since this occurs so + // rarely (when the last minted token is burnt) that we still do the swap here to avoid the gas cost of adding + // an 'if' statement (like in _removeTokenFromOwnerEnumeration) + uint256 lastTokenId = _allTokens[lastTokenIndex]; + + _allTokens[tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token + _allTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index + + // This also deletes the contents at the last position of the array + delete _allTokensIndex[tokenId]; + _allTokens.pop(); + } +} \ No newline at end of file diff --git a/contracts/external/ERC721/ERC721URIStorage.sol b/contracts/external/ERC721/ERC721URIStorage.sol index 893b895..e6a26fc 100644 --- a/contracts/external/ERC721/ERC721URIStorage.sol +++ b/contracts/external/ERC721/ERC721URIStorage.sol @@ -3,12 +3,12 @@ pragma solidity 0.6.9; -import "./ERC721.sol"; +import "./ERC721Enumerable.sol"; /** * @dev ERC721 token with storage based token URI management. */ -abstract contract ERC721URIStorage is ERC721 { +abstract contract ERC721URIStorage is ERC721Enumerable { using Strings for uint256; // Optional mapping for token URIs diff --git a/contracts/intf/IERC721Enumerable.sol b/contracts/intf/IERC721Enumerable.sol new file mode 100644 index 0000000..f845557 --- /dev/null +++ b/contracts/intf/IERC721Enumerable.sol @@ -0,0 +1,32 @@ +// This is a file copied from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC721/extensions/IERC721Enumerable.sol +// SPDX-License-Identifier: MIT + +pragma solidity 0.6.9; + +import "./IERC165.sol"; +import "./IERC721.sol"; + + +/** + * @title ERC-721 Non-Fungible Token Standard, optional enumeration extension + * @dev See https://eips.ethereum.org/EIPS/eip-721 + */ +interface IERC721Enumerable is IERC721 { + + /** + * @dev Returns the total amount of tokens stored by the contract. + */ + function totalSupply() external view returns (uint256); + + /** + * @dev Returns a token ID owned by `owner` at a given `index` of its token list. + * Use along with {balanceOf} to enumerate all of ``owner``'s tokens. + */ + function tokenOfOwnerByIndex(address owner, uint256 index) external view returns (uint256 tokenId); + + /** + * @dev Returns a token ID at a given `index` of all the tokens stored by the contract. + * Use along with {totalSupply} to enumerate all tokens. + */ + function tokenByIndex(uint256 index) external view returns (uint256); +} \ No newline at end of file