Files
openzeppelin-contracts/contracts/AddressUtils.sol
Santiago Palladino e96164feea ERC721 full implementation (#803)
* Rename current ERC721 implementation to BaseERC721

* Implement ERC721 optional & approveAll functionality

* Support for new ERC721 interface

- Tests for new features are pending
- ERC721 is abstract, since it requires metadata implementation
- Move some methods into DeprecatedERC721 contract
- Reorganise base vs full implementation
- Pending tokenByIndex

* Add more tests for ERC721

* Implement suggestions by @dekz

* Update comments in ERC721 contracts

* Implement tokensByIndex extension

- Remove restrictions from mock mint and burn calls

* Add default implementation for metadata URI

This allows token implementation to be non-abstract

* Allow operators to call approve on a token

* Remove gas stipend restriction in call to 721 receiver

* Remove deprecated implementation

We only want to keep the interface, for interacting with already deployed contracts

* Add notice to isContract helper on constract constructors

* Change natspec delimiters for consistency

* Minor linting fixes

* Add constant modifier to ERC721_RECEIVED magic value

* Use 4-params safeTransferFrom for implementing the 3-params overload

* Minor text changes in natspec comments

* Use address(0) instead of 0 or 0x0

* Use if-statements instead of boolean one-liners for clarity

:-(

* Keep ownedTokensCount state var in sync in full ERC721 implementation

* Fix incorrect comparison when burning ERC721 tokens with metadata

* Use address(0) instead of 0 in one more place in ERC721

* Throw when querying balance for the zero address

Required by the spec

* Update links to approved version of EIP721

* Use explicit size for uint

* Remove unneeded internal function in ERC721

Also rename addToken and removeToken for added clarity

* Use underscore instead of 'do' prefix for internal methods in ERC721

* Fix failing test due to events reordering in ERC721 safe transfer

* Fix bug introduced in 74db03ba06

* Remove do prefix for internal setTokenUri method

* Allow transfers to self in ERC721
2018-03-23 15:11:59 -03:00

22 lines
605 B
Solidity

pragma solidity ^0.4.18;
/**
* Utility library of inline functions on addresses
*/
library AddressUtils {
/**
* Returns whether there is code in the target address
* @dev This function will return false if invoked during the constructor of a contract,
* as the code is not actually created until after the constructor finishes.
* @param addr address address to check
* @return whether there is code in the target address
*/
function isContract(address addr) internal view returns (bool) {
uint256 size;
assembly { size := extcodesize(addr) }
return size > 0;
}
}