Debugging

Skittles supports console.log() for debugging your contracts during development. This maps directly to Hardhat's console.log, giving you a familiar TypeScript debugging experience.

Setup

Enable console.log support in your config:

skittles.config.json

{
  "consoleLog": true
}

Usage

Use console.log() in your contracts just like you would in TypeScript:

contracts/Token.ts

class Token {
  private balances: Record<address, number> = {};

  public transfer(to: address, amount: number): boolean {
    console.log("Transfer called by", msg.sender);
    console.log("Amount:", amount);

    if (this.balances[msg.sender] < amount) {
      console.log("Insufficient balance");
      throw new Error("Insufficient balance");
    }

    this.balances[msg.sender] -= amount;
    this.balances[to] += amount;
    return true;
  }
}

This compiles to Solidity with Hardhat's console import:

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

import "hardhat/console.sol";

contract Token {
    mapping(address => uint256) internal balances;

    function transfer(address to, uint256 amount) public returns (bool) {
        console.log("Transfer called by", msg.sender);
        console.log("Amount:", amount);
        require(balances[msg.sender] >= amount, "Insufficient balance");
        balances[msg.sender] -= amount;
        balances[to] += amount;
        return true;
    }
}

Supported Arguments

You can pass strings, numbers, booleans, and addresses to console.log():

console.log("hello");
console.log("balance:", amount);
console.log("sender:", msg.sender);

Production Builds

The consoleLog option defaults to false. When disabled, any console.log() calls in your contracts are automatically stripped from the compiled Solidity output. This means you can leave debug logs in your source code during development and they will be removed in production builds.

To enable console.log output during development:

skittles.config.json

{
  "consoleLog": true
}

When you're ready to deploy, simply set consoleLog to false (or remove it) and recompile — all console.log() calls will be stripped from the output.