Description:
Multi-signature wallet contract requiring multiple confirmations for transaction execution.
Blockchain: Ethereum
Source Code: View Code On The Blockchain
Solidity Source Code:
{{
"language": "Solidity",
"sources": {
"@openzeppelin/contracts/access/Ownable.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (access/Ownable.sol)
pragma solidity ^0.8.20;
import {Context} from "../utils/Context.sol";
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* The initial owner is set to the address provided by the deployer. This can
* later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
abstract contract Ownable is Context {
address private _owner;
/**
* @dev The caller account is not authorized to perform an operation.
*/
error OwnableUnauthorizedAccount(address account);
/**
* @dev The owner is not a valid owner account. (eg. `address(0)`)
*/
error OwnableInvalidOwner(address owner);
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the address provided by the deployer as the initial owner.
*/
constructor(address initialOwner) {
if (initialOwner == address(0)) {
revert OwnableInvalidOwner(address(0));
}
_transferOwnership(initialOwner);
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
_checkOwner();
_;
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if the sender is not the owner.
*/
function _checkOwner() internal view virtual {
if (owner() != _msgSender()) {
revert OwnableUnauthorizedAccount(_msgSender());
}
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby disabling any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
_transferOwnership(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
if (newOwner == address(0)) {
revert OwnableInvalidOwner(address(0));
}
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Internal function without access restriction.
*/
function _transferOwnership(address newOwner) internal virtual {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
"
},
"@openzeppelin/contracts/interfaces/draft-IERC6093.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (interfaces/draft-IERC6093.sol)
pragma solidity >=0.8.4;
/**
* @dev Standard ERC-20 Errors
* Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC-20 tokens.
*/
interface IERC20Errors {
/**
* @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
* @param balance Current balance for the interacting account.
* @param needed Minimum amount required to perform a transfer.
*/
error ERC20InsufficientBalance(address sender, uint256 balance, uint256 needed);
/**
* @dev Indicates a failure with the token `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
*/
error ERC20InvalidSender(address sender);
/**
* @dev Indicates a failure with the token `receiver`. Used in transfers.
* @param receiver Address to which tokens are being transferred.
*/
error ERC20InvalidReceiver(address receiver);
/**
* @dev Indicates a failure with the `spender`’s `allowance`. Used in transfers.
* @param spender Address that may be allowed to operate on tokens without being their owner.
* @param allowance Amount of tokens a `spender` is allowed to operate with.
* @param needed Minimum amount required to perform a transfer.
*/
error ERC20InsufficientAllowance(address spender, uint256 allowance, uint256 needed);
/**
* @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
* @param approver Address initiating an approval operation.
*/
error ERC20InvalidApprover(address approver);
/**
* @dev Indicates a failure with the `spender` to be approved. Used in approvals.
* @param spender Address that may be allowed to operate on tokens without being their owner.
*/
error ERC20InvalidSpender(address spender);
}
/**
* @dev Standard ERC-721 Errors
* Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC-721 tokens.
*/
interface IERC721Errors {
/**
* @dev Indicates that an address can't be an owner. For example, `address(0)` is a forbidden owner in ERC-20.
* Used in balance queries.
* @param owner Address of the current owner of a token.
*/
error ERC721InvalidOwner(address owner);
/**
* @dev Indicates a `tokenId` whose `owner` is the zero address.
* @param tokenId Identifier number of a token.
*/
error ERC721NonexistentToken(uint256 tokenId);
/**
* @dev Indicates an error related to the ownership over a particular token. Used in transfers.
* @param sender Address whose tokens are being transferred.
* @param tokenId Identifier number of a token.
* @param owner Address of the current owner of a token.
*/
error ERC721IncorrectOwner(address sender, uint256 tokenId, address owner);
/**
* @dev Indicates a failure with the token `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
*/
error ERC721InvalidSender(address sender);
/**
* @dev Indicates a failure with the token `receiver`. Used in transfers.
* @param receiver Address to which tokens are being transferred.
*/
error ERC721InvalidReceiver(address receiver);
/**
* @dev Indicates a failure with the `operator`’s approval. Used in transfers.
* @param operator Address that may be allowed to operate on tokens without being their owner.
* @param tokenId Identifier number of a token.
*/
error ERC721InsufficientApproval(address operator, uint256 tokenId);
/**
* @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
* @param approver Address initiating an approval operation.
*/
error ERC721InvalidApprover(address approver);
/**
* @dev Indicates a failure with the `operator` to be approved. Used in approvals.
* @param operator Address that may be allowed to operate on tokens without being their owner.
*/
error ERC721InvalidOperator(address operator);
}
/**
* @dev Standard ERC-1155 Errors
* Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC-1155 tokens.
*/
interface IERC1155Errors {
/**
* @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
* @param balance Current balance for the interacting account.
* @param needed Minimum amount required to perform a transfer.
* @param tokenId Identifier number of a token.
*/
error ERC1155InsufficientBalance(address sender, uint256 balance, uint256 needed, uint256 tokenId);
/**
* @dev Indicates a failure with the token `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
*/
error ERC1155InvalidSender(address sender);
/**
* @dev Indicates a failure with the token `receiver`. Used in transfers.
* @param receiver Address to which tokens are being transferred.
*/
error ERC1155InvalidReceiver(address receiver);
/**
* @dev Indicates a failure with the `operator`’s approval. Used in transfers.
* @param operator Address that may be allowed to operate on tokens without being their owner.
* @param owner Address of the current owner of a token.
*/
error ERC1155MissingApprovalForAll(address operator, address owner);
/**
* @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
* @param approver Address initiating an approval operation.
*/
error ERC1155InvalidApprover(address approver);
/**
* @dev Indicates a failure with the `operator` to be approved. Used in approvals.
* @param operator Address that may be allowed to operate on tokens without being their owner.
*/
error ERC1155InvalidOperator(address operator);
/**
* @dev Indicates an array length mismatch between ids and values in a safeBatchTransferFrom operation.
* Used in batch transfers.
* @param idsLength Length of the array of token identifiers
* @param valuesLength Length of the array of token amounts
*/
error ERC1155InvalidArrayLength(uint256 idsLength, uint256 valuesLength);
}
"
},
"@openzeppelin/contracts/interfaces/IERC1363.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (interfaces/IERC1363.sol)
pragma solidity >=0.6.2;
import {IERC20} from "./IERC20.sol";
import {IERC165} from "./IERC165.sol";
/**
* @title IERC1363
* @dev Interface of the ERC-1363 standard as defined in the https://eips.ethereum.org/EIPS/eip-1363[ERC-1363].
*
* Defines an extension interface for ERC-20 tokens that supports executing code on a recipient contract
* after `transfer` or `transferFrom`, or code on a spender contract after `approve`, in a single transaction.
*/
interface IERC1363 is IERC20, IERC165 {
/*
* Note: the ERC-165 identifier for this interface is 0xb0202a11.
* 0xb0202a11 ===
* bytes4(keccak256('transferAndCall(address,uint256)')) ^
* bytes4(keccak256('transferAndCall(address,uint256,bytes)')) ^
* bytes4(keccak256('transferFromAndCall(address,address,uint256)')) ^
* bytes4(keccak256('transferFromAndCall(address,address,uint256,bytes)')) ^
* bytes4(keccak256('approveAndCall(address,uint256)')) ^
* bytes4(keccak256('approveAndCall(address,uint256,bytes)'))
*/
/**
* @dev Moves a `value` amount of tokens from the caller's account to `to`
* and then calls {IERC1363Receiver-onTransferReceived} on `to`.
* @param to The address which you want to transfer to.
* @param value The amount of tokens to be transferred.
* @return A boolean value indicating whether the operation succeeded unless throwing.
*/
function transferAndCall(address to, uint256 value) external returns (bool);
/**
* @dev Moves a `value` amount of tokens from the caller's account to `to`
* and then calls {IERC1363Receiver-onTransferReceived} on `to`.
* @param to The address which you want to transfer to.
* @param value The amount of tokens to be transferred.
* @param data Additional data with no specified format, sent in call to `to`.
* @return A boolean value indicating whether the operation succeeded unless throwing.
*/
function transferAndCall(address to, uint256 value, bytes calldata data) external returns (bool);
/**
* @dev Moves a `value` amount of tokens from `from` to `to` using the allowance mechanism
* and then calls {IERC1363Receiver-onTransferReceived} on `to`.
* @param from The address which you want to send tokens from.
* @param to The address which you want to transfer to.
* @param value The amount of tokens to be transferred.
* @return A boolean value indicating whether the operation succeeded unless throwing.
*/
function transferFromAndCall(address from, address to, uint256 value) external returns (bool);
/**
* @dev Moves a `value` amount of tokens from `from` to `to` using the allowance mechanism
* and then calls {IERC1363Receiver-onTransferReceived} on `to`.
* @param from The address which you want to send tokens from.
* @param to The address which you want to transfer to.
* @param value The amount of tokens to be transferred.
* @param data Additional data with no specified format, sent in call to `to`.
* @return A boolean value indicating whether the operation succeeded unless throwing.
*/
function transferFromAndCall(address from, address to, uint256 value, bytes calldata data) external returns (bool);
/**
* @dev Sets a `value` amount of tokens as the allowance of `spender` over the
* caller's tokens and then calls {IERC1363Spender-onApprovalReceived} on `spender`.
* @param spender The address which will spend the funds.
* @param value The amount of tokens to be spent.
* @return A boolean value indicating whether the operation succeeded unless throwing.
*/
function approveAndCall(address spender, uint256 value) external returns (bool);
/**
* @dev Sets a `value` amount of tokens as the allowance of `spender` over the
* caller's tokens and then calls {IERC1363Spender-onApprovalReceived} on `spender`.
* @param spender The address which will spend the funds.
* @param value The amount of tokens to be spent.
* @param data Additional data with no specified format, sent in call to `spender`.
* @return A boolean value indicating whether the operation succeeded unless throwing.
*/
function approveAndCall(address spender, uint256 value, bytes calldata data) external returns (bool);
}
"
},
"@openzeppelin/contracts/interfaces/IERC165.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (interfaces/IERC165.sol)
pragma solidity >=0.4.16;
import {IERC165} from "../utils/introspection/IERC165.sol";
"
},
"@openzeppelin/contracts/interfaces/IERC20.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (interfaces/IERC20.sol)
pragma solidity >=0.4.16;
import {IERC20} from "../token/ERC20/IERC20.sol";
"
},
"@openzeppelin/contracts/interfaces/IERC2981.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (interfaces/IERC2981.sol)
pragma solidity >=0.6.2;
import {IERC165} from "../utils/introspection/IERC165.sol";
/**
* @dev Interface for the NFT Royalty Standard.
*
* A standardized way to retrieve royalty payment information for non-fungible tokens (NFTs) to enable universal
* support for royalty payments across all NFT marketplaces and ecosystem participants.
*/
interface IERC2981 is IERC165 {
/**
* @dev Returns how much royalty is owed and to whom, based on a sale price that may be denominated in any unit of
* exchange. The royalty amount is denominated and should be paid in that same unit of exchange.
*
* NOTE: ERC-2981 allows setting the royalty to 100% of the price. In that case all the price would be sent to the
* royalty receiver and 0 tokens to the seller. Contracts dealing with royalty should consider empty transfers.
*/
function royaltyInfo(
uint256 tokenId,
uint256 salePrice
) external view returns (address receiver, uint256 royaltyAmount);
}
"
},
"@openzeppelin/contracts/token/common/ERC2981.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (token/common/ERC2981.sol)
pragma solidity ^0.8.20;
import {IERC2981} from "../../interfaces/IERC2981.sol";
import {IERC165, ERC165} from "../../utils/introspection/ERC165.sol";
/**
* @dev Implementation of the NFT Royalty Standard, a standardized way to retrieve royalty payment information.
*
* Royalty information can be specified globally for all token ids via {_setDefaultRoyalty}, and/or individually for
* specific token ids via {_setTokenRoyalty}. The latter takes precedence over the first.
*
* Royalty is specified as a fraction of sale price. {_feeDenominator} is overridable but defaults to 10000, meaning the
* fee is specified in basis points by default.
*
* IMPORTANT: ERC-2981 only specifies a way to signal royalty information and does not enforce its payment. See
* https://eips.ethereum.org/EIPS/eip-2981#optional-royalty-payments[Rationale] in the ERC. Marketplaces are expected to
* voluntarily pay royalties together with sales, but note that this standard is not yet widely supported.
*/
abstract contract ERC2981 is IERC2981, ERC165 {
struct RoyaltyInfo {
address receiver;
uint96 royaltyFraction;
}
RoyaltyInfo private _defaultRoyaltyInfo;
mapping(uint256 tokenId => RoyaltyInfo) private _tokenRoyaltyInfo;
/**
* @dev The default royalty set is invalid (eg. (numerator / denominator) >= 1).
*/
error ERC2981InvalidDefaultRoyalty(uint256 numerator, uint256 denominator);
/**
* @dev The default royalty receiver is invalid.
*/
error ERC2981InvalidDefaultRoyaltyReceiver(address receiver);
/**
* @dev The royalty set for a specific `tokenId` is invalid (eg. (numerator / denominator) >= 1).
*/
error ERC2981InvalidTokenRoyalty(uint256 tokenId, uint256 numerator, uint256 denominator);
/**
* @dev The royalty receiver for `tokenId` is invalid.
*/
error ERC2981InvalidTokenRoyaltyReceiver(uint256 tokenId, address receiver);
/// @inheritdoc IERC165
function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165, ERC165) returns (bool) {
return interfaceId == type(IERC2981).interfaceId || super.supportsInterface(interfaceId);
}
/// @inheritdoc IERC2981
function royaltyInfo(
uint256 tokenId,
uint256 salePrice
) public view virtual returns (address receiver, uint256 amount) {
RoyaltyInfo storage _royaltyInfo = _tokenRoyaltyInfo[tokenId];
address royaltyReceiver = _royaltyInfo.receiver;
uint96 royaltyFraction = _royaltyInfo.royaltyFraction;
if (royaltyReceiver == address(0)) {
royaltyReceiver = _defaultRoyaltyInfo.receiver;
royaltyFraction = _defaultRoyaltyInfo.royaltyFraction;
}
uint256 royaltyAmount = (salePrice * royaltyFraction) / _feeDenominator();
return (royaltyReceiver, royaltyAmount);
}
/**
* @dev The denominator with which to interpret the fee set in {_setTokenRoyalty} and {_setDefaultRoyalty} as a
* fraction of the sale price. Defaults to 10000 so fees are expressed in basis points, but may be customized by an
* override.
*/
function _feeDenominator() internal pure virtual returns (uint96) {
return 10000;
}
/**
* @dev Sets the royalty information that all ids in this contract will default to.
*
* Requirements:
*
* - `receiver` cannot be the zero address.
* - `feeNumerator` cannot be greater than the fee denominator.
*/
function _setDefaultRoyalty(address receiver, uint96 feeNumerator) internal virtual {
uint256 denominator = _feeDenominator();
if (feeNumerator > denominator) {
// Royalty fee will exceed the sale price
revert ERC2981InvalidDefaultRoyalty(feeNumerator, denominator);
}
if (receiver == address(0)) {
revert ERC2981InvalidDefaultRoyaltyReceiver(address(0));
}
_defaultRoyaltyInfo = RoyaltyInfo(receiver, feeNumerator);
}
/**
* @dev Removes default royalty information.
*/
function _deleteDefaultRoyalty() internal virtual {
delete _defaultRoyaltyInfo;
}
/**
* @dev Sets the royalty information for a specific token id, overriding the global default.
*
* Requirements:
*
* - `receiver` cannot be the zero address.
* - `feeNumerator` cannot be greater than the fee denominator.
*/
function _setTokenRoyalty(uint256 tokenId, address receiver, uint96 feeNumerator) internal virtual {
uint256 denominator = _feeDenominator();
if (feeNumerator > denominator) {
// Royalty fee will exceed the sale price
revert ERC2981InvalidTokenRoyalty(tokenId, feeNumerator, denominator);
}
if (receiver == address(0)) {
revert ERC2981InvalidTokenRoyaltyReceiver(tokenId, address(0));
}
_tokenRoyaltyInfo[tokenId] = RoyaltyInfo(receiver, feeNumerator);
}
/**
* @dev Resets royalty information for the token id back to the global default.
*/
function _resetTokenRoyalty(uint256 tokenId) internal virtual {
delete _tokenRoyaltyInfo[tokenId];
}
}
"
},
"@openzeppelin/contracts/token/ERC20/IERC20.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (token/ERC20/IERC20.sol)
pragma solidity >=0.4.16;
/**
* @dev Interface of the ERC-20 standard as defined in the ERC.
*/
interface IERC20 {
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
/**
* @dev Returns the value of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the value of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves a `value` amount of tokens from the caller's account to `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address to, uint256 value) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets a `value` amount of tokens as the allowance of `spender` over the
* caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 value) external returns (bool);
/**
* @dev Moves a `value` amount of tokens from `from` to `to` using the
* allowance mechanism. `value` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(address from, address to, uint256 value) external returns (bool);
}
"
},
"@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.3.0) (token/ERC20/utils/SafeERC20.sol)
pragma solidity ^0.8.20;
import {IERC20} from "../IERC20.sol";
import {IERC1363} from "../../../interfaces/IERC1363.sol";
/**
* @title SafeERC20
* @dev Wrappers around ERC-20 operations that throw on failure (when the token
* contract returns false). Tokens that return no value (and instead revert or
* throw on failure) are also supported, non-reverting calls are assumed to be
* successful.
* To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
*/
library SafeERC20 {
/**
* @dev An operation with an ERC-20 token failed.
*/
error SafeERC20FailedOperation(address token);
/**
* @dev Indicates a failed `decreaseAllowance` request.
*/
error SafeERC20FailedDecreaseAllowance(address spender, uint256 currentAllowance, uint256 requestedDecrease);
/**
* @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/
function safeTransfer(IERC20 token, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeCall(token.transfer, (to, value)));
}
/**
* @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
* calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
*/
function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeCall(token.transferFrom, (from, to, value)));
}
/**
* @dev Variant of {safeTransfer} that returns a bool instead of reverting if the operation is not successful.
*/
function trySafeTransfer(IERC20 token, address to, uint256 value) internal returns (bool) {
return _callOptionalReturnBool(token, abi.encodeCall(token.transfer, (to, value)));
}
/**
* @dev Variant of {safeTransferFrom} that returns a bool instead of reverting if the operation is not successful.
*/
function trySafeTransferFrom(IERC20 token, address from, address to, uint256 value) internal returns (bool) {
return _callOptionalReturnBool(token, abi.encodeCall(token.transferFrom, (from, to, value)));
}
/**
* @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*
* IMPORTANT: If the token implements ERC-7674 (ERC-20 with temporary allowance), and if the "client"
* smart contract uses ERC-7674 to set temporary allowances, then the "client" smart contract should avoid using
* this function. Performing a {safeIncreaseAllowance} or {safeDecreaseAllowance} operation on a token contract
* that has a non-zero temporary allowance (for that particular owner-spender) will result in unexpected behavior.
*/
function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 oldAllowance = token.allowance(address(this), spender);
forceApprove(token, spender, oldAllowance + value);
}
/**
* @dev Decrease the calling contract's allowance toward `spender` by `requestedDecrease`. If `token` returns no
* value, non-reverting calls are assumed to be successful.
*
* IMPORTANT: If the token implements ERC-7674 (ERC-20 with temporary allowance), and if the "client"
* smart contract uses ERC-7674 to set temporary allowances, then the "client" smart contract should avoid using
* this function. Performing a {safeIncreaseAllowance} or {safeDecreaseAllowance} operation on a token contract
* that has a non-zero temporary allowance (for that particular owner-spender) will result in unexpected behavior.
*/
function safeDecreaseAllowance(IERC20 token, address spender, uint256 requestedDecrease) internal {
unchecked {
uint256 currentAllowance = token.allowance(address(this), spender);
if (currentAllowance < requestedDecrease) {
revert SafeERC20FailedDecreaseAllowance(spender, currentAllowance, requestedDecrease);
}
forceApprove(token, spender, currentAllowance - requestedDecrease);
}
}
/**
* @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
* to be set to zero before setting it to a non-zero value, such as USDT.
*
* NOTE: If the token implements ERC-7674, this function will not modify any temporary allowance. This function
* only sets the "standard" allowance. Any temporary allowance will remain active, in addition to the value being
* set here.
*/
function forceApprove(IERC20 token, address spender, uint256 value) internal {
bytes memory approvalCall = abi.encodeCall(token.approve, (spender, value));
if (!_callOptionalReturnBool(token, approvalCall)) {
_callOptionalReturn(token, abi.encodeCall(token.approve, (spender, 0)));
_callOptionalReturn(token, approvalCall);
}
}
/**
* @dev Performs an {ERC1363} transferAndCall, with a fallback to the simple {ERC20} transfer if the target has no
* code. This can be used to implement an {ERC721}-like safe transfer that rely on {ERC1363} checks when
* targeting contracts.
*
* Reverts if the returned value is other than `true`.
*/
function transferAndCallRelaxed(IERC1363 token, address to, uint256 value, bytes memory data) internal {
if (to.code.length == 0) {
safeTransfer(token, to, value);
} else if (!token.transferAndCall(to, value, data)) {
revert SafeERC20FailedOperation(address(token));
}
}
/**
* @dev Performs an {ERC1363} transferFromAndCall, with a fallback to the simple {ERC20} transferFrom if the target
* has no code. This can be used to implement an {ERC721}-like safe transfer that rely on {ERC1363} checks when
* targeting contracts.
*
* Reverts if the returned value is other than `true`.
*/
function transferFromAndCallRelaxed(
IERC1363 token,
address from,
address to,
uint256 value,
bytes memory data
) internal {
if (to.code.length == 0) {
safeTransferFrom(token, from, to, value);
} else if (!token.transferFromAndCall(from, to, value, data)) {
revert SafeERC20FailedOperation(address(token));
}
}
/**
* @dev Performs an {ERC1363} approveAndCall, with a fallback to the simple {ERC20} approve if the target has no
* code. This can be used to implement an {ERC721}-like safe transfer that rely on {ERC1363} checks when
* targeting contracts.
*
* NOTE: When the recipient address (`to`) has no code (i.e. is an EOA), this function behaves as {forceApprove}.
* Opposedly, when the recipient address (`to`) has code, this function only attempts to call {ERC1363-approveAndCall}
* once without retrying, and relies on the returned value to be true.
*
* Reverts if the returned value is other than `true`.
*/
function approveAndCallRelaxed(IERC1363 token, address to, uint256 value, bytes memory data) internal {
if (to.code.length == 0) {
forceApprove(token, to, value);
} else if (!token.approveAndCall(to, value, data)) {
revert SafeERC20FailedOperation(address(token));
}
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*
* This is a variant of {_callOptionalReturnBool} that reverts if call fails to meet the requirements.
*/
function _callOptionalReturn(IERC20 token, bytes memory data) private {
uint256 returnSize;
uint256 returnValue;
assembly ("memory-safe") {
let success := call(gas(), token, 0, add(data, 0x20), mload(data), 0, 0x20)
// bubble errors
if iszero(success) {
let ptr := mload(0x40)
returndatacopy(ptr, 0, returndatasize())
revert(ptr, returndatasize())
}
returnSize := returndatasize()
returnValue := mload(0)
}
if (returnSize == 0 ? address(token).code.length == 0 : returnValue != 1) {
revert SafeERC20FailedOperation(address(token));
}
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*
* This is a variant of {_callOptionalReturn} that silently catches all reverts and returns a bool instead.
*/
function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
bool success;
uint256 returnSize;
uint256 returnValue;
assembly ("memory-safe") {
success := call(gas(), token, 0, add(data, 0x20), mload(data), 0, 0x20)
returnSize := returndatasize()
returnValue := mload(0)
}
return success && (returnSize == 0 ? address(token).code.length > 0 : returnValue == 1);
}
}
"
},
"@openzeppelin/contracts/token/ERC721/ERC721.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (token/ERC721/ERC721.sol)
pragma solidity ^0.8.20;
import {IERC721} from "./IERC721.sol";
import {IERC721Metadata} from "./extensions/IERC721Metadata.sol";
import {ERC721Utils} from "./utils/ERC721Utils.sol";
import {Context} from "../../utils/Context.sol";
import {Strings} from "../../utils/Strings.sol";
import {IERC165, ERC165} from "../../utils/introspection/ERC165.sol";
import {IERC721Errors} from "../../interfaces/draft-IERC6093.sol";
/**
* @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC-721] Non-Fungible Token Standard, including
* the Metadata extension, but not including the Enumerable extension, which is available separately as
* {ERC721Enumerable}.
*/
abstract contract ERC721 is Context, ERC165, IERC721, IERC721Metadata, IERC721Errors {
using Strings for uint256;
// Token name
string private _name;
// Token symbol
string private _symbol;
mapping(uint256 tokenId => address) private _owners;
mapping(address owner => uint256) private _balances;
mapping(uint256 tokenId => address) private _tokenApprovals;
mapping(address owner => mapping(address operator => bool)) private _operatorApprovals;
/**
* @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
*/
constructor(string memory name_, string memory symbol_) {
_name = name_;
_symbol = symbol_;
}
/// @inheritdoc IERC165
function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
return
interfaceId == type(IERC721).interfaceId ||
interfaceId == type(IERC721Metadata).interfaceId ||
super.supportsInterface(interfaceId);
}
/// @inheritdoc IERC721
function balanceOf(address owner) public view virtual returns (uint256) {
if (owner == address(0)) {
revert ERC721InvalidOwner(address(0));
}
return _balances[owner];
}
/// @inheritdoc IERC721
function ownerOf(uint256 tokenId) public view virtual returns (address) {
return _requireOwned(tokenId);
}
/// @inheritdoc IERC721Metadata
function name() public view virtual returns (string memory) {
return _name;
}
/// @inheritdoc IERC721Metadata
function symbol() public view virtual returns (string memory) {
return _symbol;
}
/// @inheritdoc IERC721Metadata
function tokenURI(uint256 tokenId) public view virtual returns (string memory) {
_requireOwned(tokenId);
string memory baseURI = _baseURI();
return bytes(baseURI).length > 0 ? string.concat(baseURI, tokenId.toString()) : "";
}
/**
* @dev Base URI for computing {tokenURI}. If set, the resulting URI for each
* token will be the concatenation of the `baseURI` and the `tokenId`. Empty
* by default, can be overridden in child contracts.
*/
function _baseURI() internal view virtual returns (string memory) {
return "";
}
/// @inheritdoc IERC721
function approve(address to, uint256 tokenId) public virtual {
_approve(to, tokenId, _msgSender());
}
/// @inheritdoc IERC721
function getApproved(uint256 tokenId) public view virtual returns (address) {
_requireOwned(tokenId);
return _getApproved(tokenId);
}
/// @inheritdoc IERC721
function setApprovalForAll(address operator, bool approved) public virtual {
_setApprovalForAll(_msgSender(), operator, approved);
}
/// @inheritdoc IERC721
function isApprovedForAll(address owner, address operator) public view virtual returns (bool) {
return _operatorApprovals[owner][operator];
}
/// @inheritdoc IERC721
function transferFrom(address from, address to, uint256 tokenId) public virtual {
if (to == address(0)) {
revert ERC721InvalidReceiver(address(0));
}
// Setting an "auth" arguments enables the `_isAuthorized` check which verifies that the token exists
// (from != 0). Therefore, it is not needed to verify that the return value is not 0 here.
address previousOwner = _update(to, tokenId, _msgSender());
if (previousOwner != from) {
revert ERC721IncorrectOwner(from, tokenId, previousOwner);
}
}
/// @inheritdoc IERC721
function safeTransferFrom(address from, address to, uint256 tokenId) public {
safeTransferFrom(from, to, tokenId, "");
}
/// @inheritdoc IERC721
function safeTransferFrom(address from, address to, uint256 tokenId, bytes memory data) public virtual {
transferFrom(from, to, tokenId);
ERC721Utils.checkOnERC721Received(_msgSender(), from, to, tokenId, data);
}
/**
* @dev Returns the owner of the `tokenId`. Does NOT revert if token doesn't exist
*
* IMPORTANT: Any overrides to this function that add ownership of tokens not tracked by the
* core ERC-721 logic MUST be matched with the use of {_increaseBalance} to keep balances
* consistent with ownership. The invariant to preserve is that for any address `a` the value returned by
* `balanceOf(a)` must be equal to the number of tokens such that `_ownerOf(tokenId)` is `a`.
*/
function _ownerOf(uint256 tokenId) internal view virtual returns (address) {
return _owners[tokenId];
}
/**
* @dev Returns the approved address for `tokenId`. Returns 0 if `tokenId` is not minted.
*/
function _getApproved(uint256 tokenId) internal view virtual returns (address) {
return _tokenApprovals[tokenId];
}
/**
* @dev Returns whether `spender` is allowed to manage `owner`'s tokens, or `tokenId` in
* particular (ignoring whether it is owned by `owner`).
*
* WARNING: This function assumes that `owner` is the actual owner of `tokenId` and does not verify this
* assumption.
*/
function _isAuthorized(address owner, address spender, uint256 tokenId) internal view virtual returns (bool) {
return
spender != address(0) &&
(owner == spender || isApprovedForAll(owner, spender) || _getApproved(tokenId) == spender);
}
/**
* @dev Checks if `spender` can operate on `tokenId`, assuming the provided `owner` is the actual owner.
* Reverts if:
* - `spender` does not have approval from `owner` for `tokenId`.
* - `spender` does not have approval to manage all of `owner`'s assets.
*
* WARNING: This function assumes that `owner` is the actual owner of `tokenId` and does not verify this
* assumption.
*/
function _checkAuthorized(address owner, address spender, uint256 tokenId) internal view virtual {
if (!_isAuthorized(owner, spender, tokenId)) {
if (owner == address(0)) {
revert ERC721NonexistentToken(tokenId);
} else {
revert ERC721InsufficientApproval(spender, tokenId);
}
}
}
/**
* @dev Unsafe write access to the balances, used by extensions that "mint" tokens using an {ownerOf} override.
*
* NOTE: the value is limited to type(uint128).max. This protect against _balance overflow. It is unrealistic that
* a uint256 would ever overflow from increments when these increments are bounded to uint128 values.
*
* WARNING: Increasing an account's balance using this function tends to be paired with an override of the
* {_ownerOf} function to resolve the ownership of the corresponding tokens so that balances and ownership
* remain consistent with one another.
*/
function _increaseBalance(address account, uint128 value) internal virtual {
unchecked {
_balances[account] += value;
}
}
/**
* @dev Transfers `tokenId` from its current owner to `to`, or alternatively mints (or burns) if the current owner
* (or `to`) is the zero address. Returns the owner of the `tokenId` before the update.
*
* The `auth` argument is optional. If the value passed is non 0, then this function will check that
* `auth` is either the owner of the token, or approved to operate on the token (by the owner).
*
* Emits a {Transfer} event.
*
* NOTE: If overriding this function in a way that tracks balances, see also {_increaseBalance}.
*/
function _update(address to, uint256 tokenId, address auth) internal virtual returns (address) {
address from = _ownerOf(tokenId);
// Perform (optional) operator check
if (auth != address(0)) {
_checkAuthorized(from, auth, tokenId);
}
// Execute the update
if (from != address(0)) {
// Clear approval. No need to re-authorize or emit the Approval event
_approve(address(0), tokenId, address(0), false);
unchecked {
_balances[from] -= 1;
}
}
if (to != address(0)) {
unchecked {
_balances[to] += 1;
}
}
_owners[tokenId] = to;
emit Transfer(from, to, tokenId);
return from;
}
/**
* @dev Mints `tokenId` and transfers it to `to`.
*
* WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible
*
* Requirements:
*
* - `tokenId` must not exist.
* - `to` cannot be the zero address.
*
* Emits a {Transfer} event.
*/
function _mint(address to, uint256 tokenId) internal {
if (to == address(0)) {
revert ERC721InvalidReceiver(address(0));
}
address previousOwner = _update(to, tokenId, address(0));
if (previousOwner != address(0)) {
revert ERC721InvalidSender(address(0));
}
}
/**
* @dev Mints `tokenId`, transfers it to `to` and checks for `to` acceptance.
*
* Requirements:
*
* - `tokenId` must not exist.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function _safeMint(address to, uint256 tokenId) internal {
_safeMint(to, tokenId, "");
}
/**
* @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is
* forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
*/
function _safeMint(address to, uint256 tokenId, bytes memory data) internal virtual {
_mint(to, tokenId);
ERC721Utils.checkOnERC721Received(_msgSender(), address(0), to, tokenId, data);
}
/**
* @dev Destroys `tokenId`.
* The approval is cleared when the token is burned.
* This is an internal function that does not check if the sender is authorized to operate on the token.
*
* Requirements:
*
* - `tokenId` must exist.
*
* Emits a {Transfer} event.
*/
function _burn(uint256 tokenId) internal {
address previousOwner = _update(address(0), tokenId, address(0));
if (previousOwner == address(0)) {
revert ERC721NonexistentToken(tokenId);
}
}
/**
* @dev Transfers `tokenId` from `from` to `to`.
* As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
*
* Requirements:
*
* - `to` cannot be the zero address.
* - `tokenId` token must be owned by `from`.
*
* Emits a {Transfer} event.
*/
function _transfer(address from, address to, uint256 tokenId) internal {
if (to == address(0)) {
revert ERC721InvalidReceiver(address(0));
}
address previousOwner = _update(to, tokenId, address(0));
if (previousOwner == address(0)) {
revert ERC721NonexistentToken(tokenId);
} else if (previousOwner != from) {
revert ERC721IncorrectOwner(from, tokenId, previousOwner);
}
}
/**
* @dev Safely transfers `tokenId` token from `from` to `to`, checking that contract recipients
* are aware of the ERC-721 standard to prevent tokens from being forever locked.
*
* `data` is additional data, it has no specified format and it is sent in call to `to`.
*
* This internal function is like {safeTransferFrom} in the sense that it invokes
* {IERC721Receiver-onERC721Received} on the receiver, and can be used to e.g.
* implement alternative mechanisms to perform token transfer, such as signature-based.
*
* Requirements:
*
* - `tokenId` token must exist and be owned by `from`.
* - `to` cannot be the zero address.
* - `from` cannot be the zero address.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function _safeTransfer(address from, address to, uint256 tokenId) internal {
_safeTransfer(from, to, tokenId, "");
}
/**
* @dev Same as {xref-ERC721-_safeTransfer-address-address-uint256-}[`_safeTransfer`], with an additional `data` parameter which is
* forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
*/
function _safeTransfer(address from, address to, uint256 tokenId, bytes memory data) internal virtual {
_transfer(from, to, tokenId);
ERC721Utils.checkOnERC721Received(_msgSender(), from, to, tokenId, data);
}
/**
* @dev Approve `to` to operate on `tokenId`
*
* The `auth` argument is optional. If the value passed is non 0, then this function will check that `auth` is
* either the owner of the token, or approved to operate on all tokens held by this owner.
*
* Emits an {Approval} event.
*
* Overrides to this logic should be done to the variant with an additional `bool emitEvent` argument.
*/
function _approve(address to, uint256 tokenId, address auth) internal {
_approve(to, tokenId, auth, true);
}
/**
* @dev Variant of `_approve` with an optional flag to enable or disable the {Approval} event. The event is not
* emitted in the context of transfers.
*/
function _approve(address to, uint256 tokenId, address auth, bool emitEvent) internal virtual {
// Avoid reading the owner unless necessary
if (emitEvent || auth != address(0)) {
address owner = _requireOwned(tokenId);
// We do not use _isAuthorized because single-token approvals should not be able to call approve
if (auth != address(0) && owner != auth && !isApprovedForAll(owner, auth)) {
revert ERC721InvalidApprover(auth);
}
if (emitEvent) {
emit Approval(owner, to, tokenId);
}
}
_tokenApprovals[tokenId] = to;
}
/**
* @dev Approve `operator` to operate on all of `owner` tokens
*
* Requirements:
* - operator can't be the address zero.
*
* Emits an {ApprovalForAll} event.
*/
function _setApprovalForAll(address owner, address operator, bool approved) internal virtual {
if (operator == address(0)) {
revert ERC721InvalidOperator(operator);
}
_operatorApprovals[owner][operator] = approved;
emit ApprovalForAll(owner, operator, approved);
}
/**
* @dev Reverts if the `tokenId` doesn't have a current owner (it hasn't been minted, or it has been burned).
* Returns the owner.
*
* Overrides to ownership logic should be done to {_ownerOf}.
*/
function _requireOwned(uint256 tokenId) internal view returns (address) {
address owner = _ownerOf(tokenId);
if (owner == address(0)) {
revert ERC721NonexistentToken(tokenId);
}
return owner;
}
}
"
},
"@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (token/ERC721/extensions/ERC721Enumerable.sol)
pragma solidity ^0.8.20;
import {ERC721} from "../ERC721.sol";
import {IERC721Enumerable} from "./IERC721Enumerable.sol";
import {IERC165} from "../../../utils/introspection/ERC165.sol";
/**
* @dev This implements an optional extension of {ERC721} defined in the ERC that adds enumerability
* of all the token ids in the contract as well as all token ids owned by each account.
*
* CAUTION: {ERC721} extensions that implement custom `balanceOf` logic, such as {ERC721Consecutive},
* interfere with enumerability and should not be used together with {ERC721Enumerable}.
*/
abstract contract ERC721Enumerable is ERC721, IERC721Enumerable {
mapping(address owner => mapping(uint256 index => uint256)) private _ownedTokens;
mapping(uint256 tokenId => uint256) private _ownedTokensIndex;
uint256[] private _allTokens;
mapping(uint256 tokenId => uint256) private _allTokensIndex;
/**
* @dev An `owner`'s token query was out of bounds for `index`.
*
* NOTE: The owner being `address(0)` indicates a global out of bounds index.
*/
error ERC721OutOfBoundsIndex(address owner, uint256 index);
/**
* @dev Batch mint is not allowed.
*/
error ERC721EnumerableForbiddenBatchMint();
/// @inheritdoc IERC165
function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165, ERC721) returns (bool) {
return interfaceId == type(IERC721Enumerable).interfaceId || super.supportsInterface(interfaceId);
}
/// @inheritdoc IERC721Enumerable
function tokenOfOwnerByIndex(address owner, uint256 index) public view virtual returns (uint256) {
if (index >= balanceOf(owner)) {
revert ERC721OutOfBoundsIndex(owner, index);
}
return _ownedTokens[owner][index];
}
/// @inheritdoc IERC721Enumerable
function totalSupply() public view virtual returns (uint256) {
return _allTokens.length;
}
/// @inheritdoc IERC721Enumerable
function tokenByIndex(uint256 index) public view virtual returns (uint256) {
if (index >= totalSupply()) {
revert ERC721OutOfBoundsIndex(address(0), index);
}
return _allTokens[index];
}
/// @inheritdoc ERC721
function _update(address to, uint256 tokenId, address auth) internal virtual override returns (address) {
address previousOwner = super._update(to, tokenId, auth);
if (previousOwner == address(0)) {
_addTokenToAllTokensEnumeration(tokenId);
} else if (previousOwner != to) {
_removeTokenFromOwnerEnumeration(previousOwner, tokenId);
}
if (to == address(0)) {
_removeTokenFromAllTokensEnumeration(tokenId);
} else if (previousOwner != to) {
_addTokenToOwnerEnumeration(to, tokenId);
}
return previousOwner;
}
/**
* @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 = balanceOf(to) - 1;
_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 = balanceOf(from);
uint256 tokenIndex = _ownedTokensIndex[tokenId];
mapping(uint256 index => uint256) storage _ownedTokensByOwner = _ownedTokens[from];
// When the token to delete is the last token, the swap operation is unnecessary
if (tokenIndex != lastTokenIndex) {
uint256 lastTokenId = _ownedTokensByOwner[lastTokenIndex];
_ownedTokensByOwner[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 _ownedTokensByOwner[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();
}
/**
* See {ERC721-_increaseBalance}. We need that to account tokens that were minted in batch
*/
function _increaseBalance(address account, uint128 amount) internal virtual override {
if (amount > 0) {
revert ERC721EnumerableForbiddenBatchMint();
}
super._increaseBalance(account, amount);
}
}
"
},
"@openzeppelin/contracts/token/ERC721/extensions/IERC721Enumerable.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (token/ERC721/extensions/IERC721Enumerable.sol)
pragma solidity >=0.6.2;
import {IERC721} from "../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);
/**
* @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);
}
"
},
"@openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (token/ERC721/extensions/IERC721Metadata.sol)
pragma solidity >=0.6.2;
import {IERC721} from "../IERC721.sol";
/**
* @title ERC-721 Non-Fungible Token Standard, optional metadata extension
* @dev See https://eips.ethereum.org/EIPS/eip-721
*/
interface IERC721Metadata is IERC721 {
/**
* @dev Returns the token collection name.
*/
function name() external view returns (string memory);
/**
* @dev Returns the token collection symbol.
*/
function symbol() external view returns (string memory);
/**
* @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
*/
function tokenURI(uint256 tokenId) external view returns (string memory);
}
"
},
"@openzeppelin/contracts/token/ERC721/IERC721.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (token/ERC721/IERC721.sol)
pragma solidity >=0.6.2;
import {IERC165} from "../../utils/introspection/IERC165.sol";
/**
* @dev Required interface of an ERC-721 compliant contract.
*/
interface IERC721 is IERC165 {
/**
* @dev Emitted when `tokenId` token is transferred from `from` to `to`.
*/
event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
/**
* @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
*/
event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
/**
* @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
*/
event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
/**
* @dev Returns the number of tokens in ``owner``'s account.
*/
function balanceOf(address owner) external view returns (uint256 balance);
/**
* @dev Returns the owner of the `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function ownerOf(uint256 tokenId) external view returns (address owner);
/**
* @dev Safely transfers `tokenId` token from `from` to `to`.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon
* a safe transfer.
*
* Emits a {Transfer} event.
*/
function safeTransferFrom(address from, address to, uint256 tokenId, bytes calldata data) external;
/**
* @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
* are aware of the ERC-721 protocol to prevent tokens from being forever locked.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If the caller is not `from`, it must have been allowed to move this token by either {approve} or
* {setApprovalForAll}.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon
* a safe transfer.
*
* Emits a {Transfer} event.
*/
function safeTransferFrom(address from, address to, uint256 tokenId) external;
/**
* @dev Transfers `tokenId` token from `from` to `to`.
*
* WARNING: Note that the caller is responsible to confirm that the recipient is capable of receiving ERC-721
* or else they may be permanently lost. Usage of {safeTransferFrom} prevents loss, though the caller must
* understand this adds an external call which potentially creates a reentrancy vulnerability.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must be owned by `from`.
* - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
*
* Emits a {Transfer} event.
*/
function transferFrom(address from, address to, uint256 tokenId) external;
/**
* @dev Gives permission to `to` to transfer `tokenId` token to another account.
Submitted on: 2025-10-23 18:39:53
Comments
Log in to comment.
No comments yet.