Hardhat framework practice for dapp development (basics)

Prerequisite: Install node version >12, npm, git, etc.
1. Create a folder and open it with a tool you are familiar with, such as webstorm
2. After opening, run "npm init -y" and it will print on the console:

{
“name”: “76-learn-hardhat”,
“version”: “1.0.0”,
“description”: “”,
“main”: “index.js”,
“scripts”: {
“test”: “echo “Error: no test specified” && exit 1”
},
“keywords”: [],
“author”: “”,
“license”: “ISC”
}

3. Run npm install --save-dev hardhat. After success, the following is as follows:

Note: Solution to the error: npm install --save-dev “@nomiclabs/hardhat-ethers@^2.0.0” “ethereum-waffle@^3.2.0” “ethers@^5.0.0”
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4. This will create it successfully After installing the hardhat project, we can then use npx (npm subcommand) to run and test npx hardhat . The following picture will pop up to prove success.
5. During the period, you will be prompted to install some plug-ins and install them.
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6. The available command npx hardhat --help 7. Compile the contract npx hardhat compile
8. Next, rewrite a small token contract

//SPDX-License-Identifier: Unlicense
pragma solidity ^0.8.0;

import "hardhat/console.sol";

contract Token {
    
    
    string public name='my token';
    string public symbol = 'Mtn';
    uint256 public total = 100000;
    address public owner;
    mapping(address =>uint) balances;
    constructor() {
    
    
        owner = msg.sender;
        balances[msg.sender] =total;
    }

    function tranfer(address to,uint amount) external{
    
    
        balances[msg.sender] -=amount;
        balances[to] +=amount;
    }

    function getamount(address account) view external returns(uint a){
    
    
        a = balances[account];
    }
}

9. After compilation, write the test script:

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

describe("Token", function () {
    
    
  let Token, token, owner,address
  beforeEach(async ()=>{
    
    
    Token = await  ethers.getContractFactory('Token');
    token = await  Token.deploy();//部署
    [owner,address,] = await  ethers.getSigners();
  })

  describe('test',()=>{
    
    
    it('所有者', async ()=> {
    
    
        expect(await token.owner()).to.equal(owner.address);
    })

  })
});

10. Run the command to test: npx hardhat test

Note: The following error may be reported when running for the first time: Error: Cannot find module 'chai' Solution: npm install
–save-dev chai

The test runs successfully as shown below:
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Hardhat framework practice for dapp development (basics)

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