TestToken.sol

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.11;

import { ERC20, ERC20Permit } from "@openzeppelin-v5/contracts/token/ERC20/extensions/ERC20Permit.sol";

/**
 * @title Test token contract
 * @author Superfluid
 * @dev Test ERC20 token that allows any one mint new tokens.
 */
contract TestToken is ERC20Permit {
    uint256 private immutable _mintLimit;
    uint8 private _decimals;

    constructor(string memory name, string memory symbol, uint8 initDecimals, uint256 mintLimit)
        ERC20Permit(name)
        ERC20(name, symbol)
    {
        _decimals = initDecimals;
        _mintLimit = mintLimit;
    }

    /**
     * @dev See {ERC20-_mint}.
     */
    function mint(address account, uint256 amount) public returns (bool) {
        assert(amount <= _mintLimit); // no revert msg for you, bad boy
        ERC20._mint(account, amount);
        return true;
    }

    function decimals() public view override returns (uint8) {
        return _decimals;
    }
}