// SPDX-License-Identifier: MIT pragma solidity ^0.8.20; import {IERC721Receiver} from "./IERC721Receiver.sol"; import {IERC721Errors} from "./draft-IERC6093.sol"; /** * @dev Library that provide common ERC-721 utility functions. * * See https://eips.ethereum.org/EIPS/eip-721[ERC-721]. */ library ERC721Utils { /** * @dev Performs an acceptance check for the provided `operator` by calling {IERC721-onERC721Received} * on the `to` address. The `operator` is generally the address that initiated the token transfer (i.e. `msg.sender`). * * The acceptance call is not executed and treated as a no-op if the target address doesn't contain code (i.e. an EOA). * Otherwise, the recipient must implement {IERC721Receiver-onERC721Received} and return the acceptance magic value to accept * the transfer. */ function checkOnERC721Received( address operator, address from, address to, uint256 tokenId, bytes memory data ) internal { if (to.code.length > 0) { try IERC721Receiver(to).onERC721Received(operator, from, tokenId, data) returns (bytes4 retval) { if (retval != IERC721Receiver.onERC721Received.selector) { // Token rejected revert IERC721Errors.ERC721InvalidReceiver(to); } } catch (bytes memory reason) { if (reason.length == 0) { // non-IERC721Receiver implementer revert IERC721Errors.ERC721InvalidReceiver(to); } else { /// @solidity memory-safe-assembly assembly { revert(add(32, reason), mload(reason)) } } } } } }