SIZE contest - aviggiano's results

1. Define magic numbers as constant values in order to improve the code's legibility

i) MAX_BIDS

diff --git a/src/SizeSealed.sol b/src/SizeSealed.sol
index e5380ff..c43001b 100644
--- a/src/SizeSealed.sol
+++ b/src/SizeSealed.sol
@@ -13,6 +13,9 @@ import {CommonTokenMath} from "./util/CommonTokenMath.sol";
 /// @title Size Sealed Auction
 /// @author Size Market
 contract SizeSealed is ISizeSealed {
+    // Max of 1000 bids on an auction to prevent DOS
+    uint256 private constant MAX_BIDS = 1000;
+
     ///////////////////////////////
     ///          STATE          ///
     ///////////////////////////////
@@ -153,8 +156,7 @@ contract SizeSealed is ISizeSealed {
         ebid.encryptedMessage = encryptedMessage;
 
         uint256 bidIndex = a.bids.length;
-        // Max of 1000 bids on an auction to prevent DOS
-        if (bidIndex >= 1000) {
+        if (bidIndex >= MAX_BIDS) {
             revert InvalidState();
         }

ii) REVEAL_PERIOD

diff --git a/src/SizeSealed.sol b/src/SizeSealed.sol
index e5380ff..961123c 100644
--- a/src/SizeSealed.sol
+++ b/src/SizeSealed.sol
@@ -13,6 +13,8 @@ import {CommonTokenMath} from "./util/CommonTokenMath.sol";
 /// @title Size Sealed Auction
 /// @author Size Market
 contract SizeSealed is ISizeSealed {
+    uint256 private constant REVEAL_PERIOD = 24 hours;
+
     ///////////////////////////////
     ///          STATE          ///
     ///////////////////////////////
@@ -32,9 +34,9 @@ contract SizeSealed is ISizeSealed {
             if (_state != States.AcceptingBids) revert InvalidState();
         } else if (a.data.lowestQuote != type(uint128).max) {
             if (_state != States.Finalized) revert InvalidState();
-        } else if (block.timestamp <= a.timings.endTimestamp + 24 hours) {
+        } else if (block.timestamp <= a.timings.endTimestamp + REVEAL_PERIOD) {
             if (_state != States.RevealPeriod) revert InvalidState();
-        } else if (block.timestamp > a.timings.endTimestamp + 24 hours) {
+        } else if (block.timestamp > a.timings.endTimestamp + REVEAL_PERIOD) {
             if (_state != States.Voided) revert InvalidState();
         } else {
             revert();
@@ -423,7 +425,7 @@ contract SizeSealed is ISizeSealed {
 
         // Only allow bid cancellations while not finalized or in the reveal period
         if (block.timestamp >= a.timings.endTimestamp) {
-            if (a.data.lowestQuote != type(uint128).max || block.timestamp <= a.timings.endTimestamp + 24 hours) {
+            if (a.data.lowestQuote != type(uint128).max || block.timestamp <= a.timings.endTimestamp + REVEAL_PERIOD) {
                 revert InvalidState();
             }
         }

iii) CLIFF_PERCENT_BASE

diff --git a/src/SizeSealed.sol b/src/SizeSealed.sol
index e5380ff..a0b8d64 100644
--- a/src/SizeSealed.sol
+++ b/src/SizeSealed.sol
@@ -69,7 +69,7 @@ contract SizeSealed is ISizeSealed {
         if (timings.vestingStartTimestamp > timings.vestingEndTimestamp) {
             revert InvalidTimestamp();
         }
-        if (timings.cliffPercent > 1e18) {
+        if (timings.cliffPercent > CommonTokenMath.CLIFF_PERCENT_BASE) {
             revert InvalidCliffPercent();
         }
         // Revert if the min bid is more than the total reserve of the auction
diff --git a/src/util/CommonTokenMath.sol b/src/util/CommonTokenMath.sol
index 2ea350f..b8545b0 100644
--- a/src/util/CommonTokenMath.sol
+++ b/src/util/CommonTokenMath.sol
@@ -4,6 +4,7 @@ pragma solidity 0.8.17;
 import {FixedPointMathLib} from "solmate/utils/FixedPointMathLib.sol";
 
 library CommonTokenMath {
+    uint256 public constant CLIFF_PERCENT_BASE = 1e18;
 
     /*//////////////////////////////////////////////////////////////
                                 VESTING
@@ -57,7 +58,7 @@ library CommonTokenMath {
             return 0; // If cliff hasn't been triggered yet, bidder receives no tokens
         } else {
             // Vesting is active and cliff has triggered
-            uint256 cliffAmount = FixedPointMathLib.mulDivDown(baseAmount, cliffPercent, 1e18);
+            uint256 cliffAmount = FixedPointMathLib.mulDivDown(baseAmount, cliffPercent, CLIFF_PERCENT_BASE);
 
             return uint128(
                 cliffAmount

1. Delete storage variable on SizeSealed.refund instead of simply setting sender to nul for higher gas refunds

Code changes

diff --git a/src/SizeSealed.sol b/src/SizeSealed.sol
index e5380ff..1b75d05 100644
--- a/src/SizeSealed.sol
+++ b/src/SizeSealed.sol
@@ -344,11 +344,12 @@ contract SizeSealed is ISizeSealed {
             revert InvalidState();
         }
 
-        b.sender = address(0);
+        uint256 quoteAmount = b.quoteAmount;
+        delete a.bids[bidIndex];
 
         emit BidRefund(auctionId, bidIndex);
 
-        SafeTransferLib.safeTransfer(ERC20(a.params.quoteToken), msg.sender, b.quoteAmount);
+        SafeTransferLib.safeTransfer(ERC20(a.params.quoteToken), msg.sender, quoteAmount);
     }
 
     /// @notice Called after finalize for successful bidders

Gas diff

$ forge snapshot --diff .gas-snapshot
...
testCancelSingleBid() (gas: -12 (-0.002%))
testCancelBidDuringVoidedNoFinalize() (gas: -12 (-0.002%))
testCancelAuction() (gas: -12 (-0.004%))
testCancelAuctionDuringRevealPeriod() (gas: -12 (-0.004%))
testAuctionRefundLostBidder() (gas: -98628 (-10.846%))
Overall gas change: -98676 (-10.859%)

2. Delete storage variable on SizeSealed.cancelBid` instead of simply setting properties to nul for higher gas refunds

Code changes

diff --git a/src/SizeSealed.sol b/src/SizeSealed.sol
index e5380ff..e475ba0 100644
--- a/src/SizeSealed.sol
+++ b/src/SizeSealed.sol
@@ -428,15 +428,14 @@ contract SizeSealed is ISizeSealed {
             }
         }
 
+        uint256 quoteAmount = b.quoteAmount;
         // Prevent any futher access to this EncryptedBid
-        b.sender = address(0);
-
         // Prevent seller from finalizing a cancelled bid
-        b.commitment = 0;
+        delete a.bids[bidIndex];
 
         emit BidCancelled(auctionId, bidIndex);
 
-        SafeTransferLib.safeTransfer(ERC20(a.params.quoteToken), msg.sender, b.quoteAmount);
+        SafeTransferLib.safeTransfer(ERC20(a.params.quoteToken), msg.sender, quoteAmount);
     }
 
     ////////////////////////////////////////////////////////////////////////////

Gas diff

$ forge snapshot --diff .gas-snapshot
...
testAuctionRefundLostBidder() (gas: -12 (-0.001%))
testCancelBidDuringRevealBeforeFinalize() (gas: -16 (-0.003%))
testCancelAuction() (gas: -12 (-0.004%))
testCancelAuctionDuringRevealPeriod() (gas: -12 (-0.004%))
testCancelBidAfterFinalize() (gas: -32 (-0.005%))
testCancelBidDuringVoidedNoFinalize() (gas: -61462 (-11.399%))
testCancelSingleBid() (gas: -63386 (-11.548%))
Overall gas change: -124932 (-22.964%)