NoBey/openzeppelin-contracts
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Keep ownedTokensCount state var in sync in full ERC721 implementation

Browse Source
This commit is contained in:
Santiago Palladino
2018-03-21 11:56:42 -03:00
parent 3f2ea8a329
commit 74db03ba06
1 changed files with 2 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

15
contracts/token/ERC721/ERC721Token.sol
View File

@ -41,15 +41,6 @@ contract ERC721Token is ERC721, ERC721BasicToken {
symbol_ = _symbol;
}
/**
* @dev Gets the balance of the specified address
* @param _owner address to query the balance of
* @return uint256 representing the amount owned by the passed address
*/
function balanceOf(address _owner) public view returns (uint256) {
return ownedTokens[_owner].length;
}
/**
* @dev Gets the token name
* @return string representing the token name
@ -123,8 +114,7 @@ contract ERC721Token is ERC721, ERC721BasicToken {
* @param _tokenId uint256 ID of the token to be added to the tokens list of the given address
*/
function addToken(address _to, uint256 _tokenId) internal {
require(tokenOwner[_tokenId] == address(0));
tokenOwner[_tokenId] = _to;
super.addToken(_to, _tokenId);
uint256 length = balanceOf(_to);
ownedTokens[_to].push(_tokenId);
ownedTokensIndex[_tokenId] = length;
@ -136,13 +126,12 @@ contract ERC721Token is ERC721, ERC721BasicToken {
* @param _tokenId uint256 ID of the token to be removed from the tokens list of the given address
*/
function removeToken(address _from, uint256 _tokenId) internal {
require(ownerOf(_tokenId) == _from);
super.removeToken(_from, _tokenId);
uint256 tokenIndex = ownedTokensIndex[_tokenId];
uint256 lastTokenIndex = balanceOf(_from).sub(1);
uint256 lastToken = ownedTokens[_from][lastTokenIndex];
tokenOwner[_tokenId] = 0;
ownedTokens[_from][tokenIndex] = lastToken;
ownedTokens[_from][lastTokenIndex] = 0;
// Note that this will handle single-element arrays. In that case, both tokenIndex and lastTokenIndex are going to