reason-string

July 2, 2025 · View on GitHub

Recommended Badge Category Badge Default Severity Badge warn

The {"extends": "solhint:recommended"} property in a configuration file enables this rule.

Description

Require or revert statement must have a reason string and check that each reason string is at most N characters long.

Options

This rule accepts an array of options:

IndexDescriptionDefault Value
0Rule severity. Must be one of "error", "warn", "off".warn
1A JSON object with a single property "maxLength" specifying the max number of characters per reason string.{"maxLength":32}

Example Config

{
  "rules": {
    "reason-string": [
      "warn",
      {
        "maxLength": 32
      }
    ]
  }
}

Examples

👍 Examples of correct code for this rule

Require with reason string


      pragma solidity 0.4.4;
        
        
      contract A {
        
        function b() public {
          require(!has(role, account), "Roles: account already has role");
          role.bearer[account] = true;
          role.bearer[account] = true;
        }
    
      }

👎 Examples of incorrect code for this rule

Require without reason string


      pragma solidity 0.4.4;
        
        
      contract A {
        
        function b() public {
          require(!has(role, account));
          role.bearer[account] = true;
          role.bearer[account] = true;
        }
    
      }

Version

This rule was introduced in Solhint 5.0.4

Resources