@openzeppelin/contracts
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Changelog
4.8.0 (2022-11-08)
TimelockController
: Added a new admin
constructor parameter that is assigned the admin role instead of the deployer account. (#3722)Initializable
: add internal functions _getInitializedVersion
and _isInitializing
(#3598)ERC165Checker
: add supportsERC165InterfaceUnchecked
for consulting individual interfaces without the full ERC165 protocol. (#3339)Address
: optimize functionCall
by calling functionCallWithValue
directly. (#3468)Address
: optimize functionCall
functions by checking contract size only if there is no returned data. (#3469)Governor
: make the relay
function payable, and add support for EOA payments. (#3730)GovernorCompatibilityBravo
: remove unused using
statements. (#3506)ERC20
: optimize _transfer
, _mint
and _burn
by using unchecked
arithmetic when possible. (#3513)ERC20Votes
, ERC721Votes
: optimize getPastVotes
for looking up recent checkpoints. (#3673)ERC20FlashMint
: add an internal _flashFee
function for overriding. (#3551)ERC4626
: use the same decimals()
as the underlying asset by default (if available). (#3639)ERC4626
: add internal _initialConvertToShares
and _initialConvertToAssets
functions to customize empty vaults behavior. (#3639)ERC721
: optimize transfers by making approval clearing implicit instead of emitting an event. (#3481)ERC721
: optimize burn by making approval clearing implicit instead of emitting an event. (#3538)ERC721
: Fix balance accounting when a custom _beforeTokenTransfer
hook results in a transfer of the token under consideration. (#3611)ERC721
: use unchecked arithmetic for balance updates. (#3524)ERC721Consecutive
: Implementation of EIP-2309 that allows batch minting of ERC721 tokens during construction. (#3311)ReentrancyGuard
: Reduce code size impact of the modifier by using internal functions. (#3515)SafeCast
: optimize downcasting of signed integers. (#3565)ECDSA
: Remove redundant check on the v
value. (#3591)VestingWallet
: add releasable
getters. (#3580)VestingWallet
: remove unused library Math.sol
. (#3605)VestingWallet
: make constructor payable. (#3665)Create2
: optimize address computation by using assembly instead of abi.encodePacked
. (#3600)Clones
: optimized the assembly to use only the scratch space during deployments, and optimized predictDeterministicAddress
to use fewer operations. (#3640)Checkpoints
: Use procedural generation to support multiple key/value lengths. (#3589)Checkpoints
: Add new lookup mechanisms. (#3589)Arrays
: Add unsafeAccess
functions that allow reading and writing to an element in a storage array bypassing Solidity's "out-of-bounds" check. (#3589)Strings
: optimize toString
. (#3573)Ownable2Step
: extension of Ownable
that makes the ownership transfers a two step process. (#3620)Math
and SignedMath
: optimize function max
by using >
instead of >=
. (#3679)Math
: Add log2
, log10
and log256
. (#3670)ERC721
: In order to add support for batch minting via ERC721Consecutive
it was necessary to make a minor breaking change in the internal interface of ERC721
. Namely, the hooks _beforeTokenTransfer
and _afterTokenTransfer
have one additional argument that may need to be added to overrides: function _beforeTokenTransfer(
address from,
address to,
uint256 tokenId,
+ uint256 batchSize
) internal virtual override
ERC4626
: Conversion from shares to assets (and vice-versa) in an empty vault used to consider the possible mismatch between the underlying asset's and the vault's decimals. This initial conversion rate is now set to 1-to-1 irrespective of decimals, which are meant for usability purposes only. The vault now uses the assets decimals by default, so off-chain the numbers should appear the same. Developers overriding the vault decimals to a value that does not match the underlying asset may want to override the _initialConvertToShares
and _initialConvertToAssets
to replicate the previous behavior.
TimelockController
: During deployment, the TimelockController used to grant the TIMELOCK_ADMIN_ROLE
to the deployer and to the timelock itself. The deployer was then expected to renounce this role once configuration of the timelock is over. Failing to renounce that role allows the deployer to change the timelock permissions (but not to bypass the delay for any time-locked actions). The role is no longer given to the deployer by default. A new parameter admin
can be set to a non-zero address to grant the admin role during construction (to the deployer or any other address). Just like previously, this admin role should be renounced after configuration. If this param is given address(0)
, the role is not allocated and doesn't need to be revoked. In any case, the timelock itself continues to have this role.
EIP712
: Added the file EIP712.sol
and deprecated draft-EIP712.sol
since the EIP is no longer a Draft. Developers are encouraged to update their imports. (#3621)-import "@openzeppelin/contracts/utils/cryptography/draft-EIP712.sol";
+import "@openzeppelin/contracts/utils/cryptography/EIP712.sol";
ERC721Votes
: Added the file ERC721Votes.sol
and deprecated draft-ERC721Votes.sol
since it no longer depends on a Draft EIP (EIP-712). Developers are encouraged to update their imports. (#3699)-import "@openzeppelin/contracts/token/ERC721/extensions/draft-ERC721Votes.sol";
+import "@openzeppelin/contracts/token/ERC721/extensions/ERC721Votes.sol";
ERC-721 integrators that interpret contract state from events should make sure that they implement the clearing of approval that is implicit in every transfer according to the EIP. Previous versions of OpenZeppelin Contracts emitted an explicit Approval
event even though it was not required by the specification, and this is no longer the case.
With the new ERC721Consecutive
extension, the internal workings of ERC721
are slightly changed. Custom extensions to ERC721 should be reviewed to ensure they remain correct. The internal functions that should be considered are _ownerOf
(new), _beforeTokenTransfer
, and _afterTokenTransfer
.
Existing ERC4626
contracts that are upgraded to 4.8 must initialize a new variable that holds the vault token decimals. The recommended way to do this is to use a [reinitializer]:
function migrateToV48() public reinitializer(2) {
__ERC4626_init(IERC20Upgradeable(asset()));
}
Changelog
4.7.3 (2022-08-10)
ECDSA
: recover(bytes32,bytes)
and tryRecover(bytes32,bytes)
no longer accept compact signatures to prevent malleability. Compact signature support remains available using recover(bytes32,bytes32,bytes32)
and tryRecover(bytes32,bytes32,bytes32)
.Changelog
4.7.2 (2022-07-25)
LibArbitrumL2
, CrossChainEnabledArbitrumL2
: Fixed detection of cross-chain calls for EOAs. Previously, calls from EOAs would be classified as cross-chain calls. (#3578)GovernorVotesQuorumFraction
: Fixed quorum updates so they do not affect past proposals that failed due to lack of quorum. (#3561)ERC165Checker
: Added protection against large returndata. (#3587)Changelog
4.7.0 (2022-06-29)
TimelockController
: Migrate _call
to _execute
and allow inheritance and overriding similar to Governor
. (#3317)CrossChainEnabledPolygonChild
: replace the require
statement with the custom error NotCrossChainCall
. (#3380)ERC20FlashMint
: Add customizable flash fee receiver. (#3327)ERC4626
: add an extension of ERC20
that implements the ERC4626 Tokenized Vault Standard. (#3171)SafeERC20
: add safePermit
as mitigation against phantom permit functions. (#3280)Math
: add a mulDiv
function that can round the result either up or down. (#3171)Math
: Add a sqrt
function to compute square roots of integers, rounding either up or down. (#3242)Strings
: add a new overloaded function toHexString
that converts an address
with fixed length of 20 bytes to its not checksummed ASCII string
hexadecimal representation. (#3403)EnumerableMap
: add new UintToUintMap
map type. (#3338)EnumerableMap
: add new Bytes32ToUintMap
map type. (#3416)SafeCast
: add support for many more types, using procedural code generation. (#3245)MerkleProof
: add multiProofVerify
to prove multiple values are part of a Merkle tree. (#3276)MerkleProof
: add calldata versions of the functions to avoid copying input arrays to memory and save gas. (#3200)ERC721
, ERC1155
: simplified revert reasons. (#3254, (#3438))ERC721
: removed redundant require statement. (#3434)PaymentSplitter
: add releasable
getters. (#3350)Initializable
: refactored implementation of modifiers for easier understanding. (#3450)Proxies
: remove runtime check of ERC1967 storage slots. (#3455)Initializable
: functions decorated with the modifier reinitializer(1)
may no longer invoke each other.