https://github.com/code-423n4/2022-12-caviar/blob/main/src/lib/SafeERC20Namer.sol
--- a/src/lib/SafeERC20Namer.sol
+++ b/src/lib/SafeERC20Namer.sol
@@ -7,40 +7,10 @@ import "openzeppelin/utils/Strings.sol";
// produces token descriptors from inconsistent or absent ERC20 symbol implementations that can return string or bytes32
// this library will always produce a string symbol to represent the token
library SafeERC20Namer {
- function bytes32ToString(bytes32 x) private pure returns (string memory) {
- bytes memory bytesString = new bytes(32);
- uint256 charCount = 0;
- for (uint256 j = 0; j < 32; j++) {
- bytes1 char = x[j];
- if (char != 0) {
- bytesString[charCount] = char;
- charCount++;
- }
- }
-
- bytes memory bytesStringTrimmed = new bytes(charCount);
- for (uint256 j = 0; j < charCount; j++) {
- bytesStringTrimmed[j] = bytesString[j];
- }
-
- return string(bytesStringTrimmed);
- }
// assumes the data is in position 2
function parseStringData(bytes memory b) private pure returns (string memory) {
- uint256 charCount = 0;
- // first parse the charCount out of the data
- for (uint256 i = 32; i < 64; i++) {
- charCount <<= 8;
- charCount += uint8(b[i]);
- }
-
- bytes memory bytesStringTrimmed = new bytes(charCount);
- for (uint256 i = 0; i < charCount; i++) {
- bytesStringTrimmed[i] = b[i + 64];
- }
-
- return string(bytesStringTrimmed);
+ return string(abi.encodePacked(b));
}
// uses a heuristic to produce a token name from the address
@@ -59,17 +29,11 @@ library SafeERC20Namer {
function callAndParseStringReturn(address token, bytes4 selector) private view returns (string memory) {
(bool success, bytes memory data) = token.staticcall(abi.encodeWithSelector(selector));
// if not implemented, or returns empty data, return empty string
- if (!success || data.length == 0) {
+ if (!success) {
return "";
}
- // bytes32 data always has length 32
- if (data.length == 32) {
- bytes32 decoded = abi.decode(data, (bytes32));
- return bytes32ToString(decoded);
- } else if (data.length > 64) {
- return abi.decode(data, (string));
- }
- return "";
+
+ return string(abi.encodePacked(data));
}Gas report diff results on Create.t.sol
# forge snapshot --diff .gas-snapshot --match-contract Create
Running 6 tests for test/Caviar/Create.t.sol:CreateTest
[PASS] testItEmitsCreateEvent() (gas: 3424124)
[PASS] testItReturnsPair() (gas: 3419438)
[PASS] testItRevertsIfDeployingSamePairTwice() (gas: 3423667)
[PASS] testItSavesPair() (gas: 3420842)
[PASS] testItSavesPair(address,address,bytes32) (runs: 256, μ: 3457811, ~: 3475546)
[PASS] testItSetsSymbolsAndNames() (gas: 3486364)
Test result: ok. 6 passed; 0 failed; finished in 234.20ms
testItSetsSymbolsAndNames() (gas: -423593 (-10.834%))
testItRevertsIfDeployingSamePairTwice() (gas: -423593 (-11.010%))
testItSavesPair() (gas: -423582 (-11.018%))
testItReturnsPair() (gas: -423687 (-11.025%))
Overall gas change: -1694455 (-43.887%)--- a/src/Pair.sol
+++ b/src/Pair.sol
@@ -235,8 +235,10 @@ contract Pair is ERC20, ERC721TokenReceiver {
// *** Interactions *** //
// transfer nfts from sender
- for (uint256 i = 0; i < tokenIds.length; i++) {
+ for (uint256 i = 0; i < tokenIds.length;) {
ERC721(nft).safeTransferFrom(msg.sender, address(this), tokenIds[i]);
+
+ unchecked { ++i; }
}
emit Wrap(tokenIds);
@@ -255,8 +257,10 @@ contract Pair is ERC20, ERC721TokenReceiver {
// *** Interactions *** //
// transfer nfts to sender
- for (uint256 i = 0; i < tokenIds.length; i++) {
+ for (uint256 i = 0; i < tokenIds.length;) {
ERC721(nft).safeTransferFrom(address(this), msg.sender, tokenIds[i]);
+
+ unchecked { ++i; }
}
emit Unwrap(tokenIds);
@@ -465,9 +469,11 @@ contract Pair is ERC20, ERC721TokenReceiver {
if (merkleRoot == bytes23(0)) return;
// validate merkle proofs against merkle root
- for (uint256 i = 0; i < tokenIds.length; i++) {
+ for (uint256 i = 0; i < tokenIds.length;) {
bool isValid = MerkleProofLib.verify(proofs[i], merkleRoot, keccak256(abi.encodePacked(tokenIds[i])));
require(isValid, "Invalid merkle proof");
+
+ unchecked { ++i; }
}
}# forge snapshot --diff .gas-snapshot
testItReturnsBaseTokenAmountAndFractionalTokenAmount() (gas: 11 (0.011%))
testItReturnsInputAmount() (gas: -19 (-0.034%))
testItTransfersBaseTokens() (gas: -27 (-0.045%))
testItRefundsSurplusEther() (gas: -30 (-0.051%))
testItTransfersBaseTokens() (gas: 61 (0.060%))
testItRevertsSlippageOnSell() (gas: -15 (-0.062%))
testItTransfersBaseTokens() (gas: 53 (0.086%))
testItRevertsFractionalTokenSlippage() (gas: -30 (-0.105%))
testItInitMintsLpTokensToSender() (gas: 138 (0.111%))
testItTransfersBaseTokens() (gas: 144 (0.114%))
testItBurnsLpTokens() (gas: 129 (0.127%))
testItTransfersEther() (gas: 37 (0.136%))
testItTransfersEther() (gas: 168 (0.172%))
testItTransfersEther() (gas: 128 (0.183%))
testItTransfersEther() (gas: 90 (0.184%))
testItReturnsOutputAmount() (gas: -99 (-0.187%))
testItTransfersFractionalTokens() (gas: 109 (0.190%))
testItTransfersFractionalTokens() (gas: 197 (0.197%))
testItBuysSellsEqualAmounts(uint256) (gas: 436 (0.203%))
testItReturnsOutputAmount() (gas: 365 (0.212%))
testItTransfersFractionalTokens() (gas: 268 (0.216%))
testItRevertsSlippageAfterInitMint() (gas: 301 (0.225%))
testItInitMintsLpTokensToSender() (gas: 606 (0.232%))
testItTransfersBaseTokens() (gas: 612 (0.233%))
testItTransfersBaseTokens() (gas: 437 (0.244%))
testItRevertsBaseTokenSlippage() (gas: 72 (0.253%))
testItRevertsSlippageOnSell() (gas: 449 (0.275%))
testItMintsFractionalTokens() (gas: 505 (0.286%))
testItTransfersFractionalTokens() (gas: 189 (0.316%))
testItMintsLpTokensAfterInit() (gas: 1793 (0.328%))
testItMintsLpTokensAfterInit() (gas: 2866 (0.337%))
testItAddsBuysSellsRemovesCorrectAmount(uint256,uint256,uint256) (gas: 2729 (0.348%))
testItRevertsSlippageOnInitMint() (gas: 645 (0.365%))
testItTransfersNfts() (gas: 993 (0.373%))
testCannotExitIfNotAdmin() (gas: 66 (0.389%))
testItRevertsSlippageAfterInitMint() (gas: 1819 (0.392%))
testItMintsLpTokensAfterInitWithEther() (gas: 1272 (0.400%))
testItTransfersNfts() (gas: 800 (0.441%))
testItRevertsSlippageOnBuy() (gas: 116 (0.485%))
testItTransfersNftsAfterWithdraw() (gas: 444 (0.604%))
testItBurnsFractionalTokens() (gas: 717 (0.618%))
testItAddsWithMerkleProof() (gas: 30267 (0.633%))
testItSellsWithMerkleProof() (gas: 32090 (0.643%))
testExitSetsCloseTimestamp() (gas: 272 (0.707%))
testCannotWithdrawIfNotClosed() (gas: 119 (0.753%))
testCannotWithdrawIfNotEnoughTimeElapsed() (gas: 323 (0.767%))
testItTransfersTokens() (gas: 949 (0.788%))
testItRevertsSlippageOnInitMint() (gas: 162 (0.803%))
testCannotWithdrawIfNotAdmin() (gas: 343 (0.813%))
testItTransfersNfts() (gas: -2082 (-1.221%))
testItTransfersBaseTokens() (gas: -2199 (-1.287%))
testItBurnsLpTokens() (gas: -2200 (-1.290%))
testItReturnsBaseTokenAmountAndFractionalTokenAmount() (gas: -2277 (-1.382%))
testItTransfersNfts() (gas: -2102 (-1.644%))
testItTransfersBaseTokens() (gas: -2286 (-1.780%))
testItBurnsFractionalTokens() (gas: -2261 (-1.827%))
testItReturnsInputAmount() (gas: -2342 (-1.923%))
testItMintsFractionalTokens() (gas: 3161 (1.933%))
testItTransfersTokens() (gas: 3542 (2.075%))
testItRevertsNftSlippage() (gas: -2608 (-3.957%))
testItRevertsBaseTokenSlippage() (gas: -2558 (-6.305%))
testItRevertsSlippageOnBuy() (gas: -2468 (-7.342%))
testItSetsSymbolsAndNames() (gas: -423593 (-10.834%))
testItRevertsIfDeployingSamePairTwice() (gas: -423593 (-11.010%))
testItSavesPair() (gas: -423582 (-11.018%))
testItReturnsPair() (gas: -423687 (-11.025%))
testItRevertsIfMaxInputAmountIsNotEqualToValue() (gas: -2777 (-12.364%))
testItRevertsIfValueDoesNotMatchBaseTokenAmount() (gas: -6130 (-18.348%))
testItRevertsIfValueIsNot0AndBaseTokenIsNot0() (gas: -6117 (-18.440%))
testItRevertsIfValueIsGreaterThanZeroAndBaseTokenIsNot0() (gas: -8082 (-29.316%))Overall gas change: -1652171 (-133.538%)