调用合约方法创建子合约后获取子合约地址

在通过调用合约的方法创建合约后，不能直接得到子合约地址。不便于单元测试。如下方法可解决：

合约：

// SPDX-License-Identifier: GPL-3.0pragma solidity ^0.8.13;contract A {// 子合约string public name;}contract B {// 父合约event NEWA(address addr); //定义事件address private aa; // 用来验证function createA() public returns (A){// 创建A合约A a = new A();aa = address(a);emit NEWA(address(a));// 发送事件return a;}function getaa() public view returns (address){return aa;}}

单元测试：

const { expect } = require('chai');const { ethers } = require('hardhat');describe('Test', () => {let owner, user1, users, contract;it('Should return address of sub-contract.', async () => {[ owner, user1, ...users ] = await ethers.getSigners();const Contract = await ethers.getContractFactory('B');contract = await Contract.deploy(); // 部署父合约Bconst exec = await contract.createA();// 通过B合约创建子合约Aconst event = await exec.wait();const Baddr = ethers.utils.getAddress(// 标准化为地址格式ethers.utils.hexStripZeros( // 去0event.events[0].data// 读取事件的值));expect(await contract.getaa()).to.equal(Baddr);});});