Hardhat-创建项目，编译，测试初体验在正文的第一句加入“我正在参加「码上掘金挑战赛」详情请看：码上掘金挑战赛来了

在正文的第一句加入“我正在参加「码上掘金挑战赛」详情请看：码上掘金挑战赛来了！

首先环境搭建

需要安装nodejs，建议版本用16以上

创建项目

新建一个项目文件

执行初始化指令： yarn init
安装Hardhat： yarn add --dev hardhat
进入安装目录执行： npx hardhat
选择创建一个空的项目

安装插件（可以不安装）

 yarn add --dev @nomicfoundation/hardhat-toolbox @nomicfoundation/hardhat-network-helpers @nomicfoundation/hardhat-chai-matchers @nomiclabs/hardhat-ethers @nomiclabs/hardhat-etherscan chai ethers hardhat-gas-reporter solidity-coverage @typechain/hardhat typechain @typechain/ethers-v5 @ethersproject/abi @ethersproject/providers

6.在根目录新建一个contracts文件夹用了存放合约文件

7.新建一个Token.sol文件

//SPDX-License-Identifier: UNLICENSED

// Solidity files have to start with this pragma.
// It will be used by the Solidity compiler to validate its version.
pragma solidity ^0.8.17;

// This is the main building block for smart contracts.
contract Token {
    // Some string type variables to identify the token.
    string public name = "My Hardhat Token";
    string public symbol = "MHT";

    // The fixed amount of tokens, stored in an unsigned integer type variable.
    uint256 public totalSupply = 1000000;

    // An address type variable is used to store ethereum accounts.
    address public owner;

    // A mapping is a key/value map. Here we store each account's balance.
    mapping(address => uint256) balances;

    // The Transfer event helps off-chain applications understand
    // what happens within your contract.
    event Transfer(address indexed _from, address indexed _to, uint256 _value);

    /**
     * Contract initialization.
     */
    constructor() {
        // The totalSupply is assigned to the transaction sender, which is the
        // account that is deploying the contract.
        balances[msg.sender] = totalSupply;
        owner = msg.sender;
    }

    function transfer(address to, uint256 amount) external {
        // Check if the transaction sender has enough tokens.
        // If `require`'s first argument evaluates to `false` then the
        // transaction will revert.
        require(balances[msg.sender] >= amount, "Not enough tokens");

        // Transfer the amount.
        balances[msg.sender] -= amount;
        balances[to] += amount;

        // Notify off-chain applications of the transfer.
        emit Transfer(msg.sender, to, amount);
    }
    function balanceOf(address account) external view returns (uint256) {
        return balances[account];
    }
}

编译token合约命令：npx hardhat compile

运行之后发现报错，报错信息

查看hardhat的错误文档

需要安装 solc yarn global add solc

9.再次执行： npx hardhat compile

编译成功

10.在项目的根目录新建一个test文件和Token.js的文件

token.js的代码如下

const { expect } = require("chai");

describe("Token contract", function () {
  it("Deployment should assign the total supply of tokens to the owner", async function () {
    const [owner] = await ethers.getSigners();

    const Token = await ethers.getContractFactory("Token");

    const hardhatToken = await Token.deploy();

    const ownerBalance = await hardhatToken.balanceOf(owner.address);
    expect(await hardhatToken.totalSupply()).to.equal(ownerBalance);
  });
});