ArkProject: NFT Bridge

Summary

Literal values are repeatedly used across multiple files in the codebase, which could lead to inconsistencies and difficulties in maintenance. Defining these literals as constant variables will improve code readability and maintainability.

Instances

1. File: src/Escrow.sol

   • Lines: 86, 107

     // Line 86

     require(amount >= 100, "Minimum amount required.");

     ​

     // Line 107

     uint256 fee = (amount * 2) / 100;

     ​

2. File: src/Protocol.sol

   • Lines: 177, 228

     // Line 177

     uint256 constant RATE = 2500;

     ​

     // Line 228

     uint256 threshold = 5000;

3. File: src/sn/Cairo.sol

   • Lines: 128, 149, 239, 451

     // Line 128

     buf[offset] = uint128(val & 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF);

     ​

     // Line 149

     buf[offset + 1] = uint128(val >> 128);

     ​

     // Line 239

     uint256 constant MAX_UINT128 = 2**128 - 1;

     ​

     // Line 451

     require(val <= MAX_UINT128, "Value exceeds maximum.");

Impact on Project:

• Maintainability: Using constants instead of literals reduces the risk of errors during code updates and improves the readability of the code.

• Consistency: Defining constants ensures consistent usage across the codebase, minimizing discrepancies and potential bugs.

Recommendations

1. Consistent Usage: Replace all repeated literals with constant variables across the codebase.

2. Code Review: Perform a thorough code review to identify any additional instances where literals could be replaced with constants.

Suggested Code Refactoring

1. In src/Protocol.sol:

   // Define constant values

   uint256 constant BASE_LENGTH = 7;

   ​

   // Replace literals with constants

   uint256 len = BASE_LENGTH;

2. In src/sn/Cairo.sol:

   // Define constants

   uint256 constant LOW_PART = 128;

   uint256 constant HIGH_PART = 128;

   ​

   // Refactor the serialization function

   buf[offset] = uint128(val);

   buf[offset + 1] = uint128(val >> LOW_PART);