使用 ethers js 运行安全帽测试时，合同事件侦听器未触发

如何解决使用 ethers js 运行安全帽测试时，合同事件侦听器未触发

这是一个非常小的存储库来显示问题：https://github.com/adamdry/ethers-event-issue

但我也会在这里解释一下。这是我的合同：

//SPDX-License-Identifier: UNLICENSED;
pragma solidity 0.8.4;

contract ContractA {

    event TokensMinted(uint amount);

    function mint(uint amount) public {
        emit TokensMinted(amount);
    }

}

这是我的测试代码：

import * as chai from 'chai'
import { BigNumber,ContractTransaction } from 'ethers'
import { ethers } from 'hardhat'
import { ContractA,ContractAFactory } from '../typechain'

const expect = chai.expect

describe("Example test",function () {
    it("should fire the event",async function () {
        const [owner] = await ethers.getSigners();

        const contractAFactory = (await ethers.getContractFactory(
            'ContractA',owner,)) as ContractAFactory

        const contractA: ContractA = await contractAFactory.deploy()

        contractA.on('TokensMinted',(amount: BigNumber) => {
            // THIS LINE NEVER GETS HIT
            console.log('###########')
        })

        const contractTx: ContractTransaction = await contractA.mint(123)
        const contractReceipt: ContractReceipt = await contractTx.wait()

        for (const event of contractReceipt.events!) {
            console.log(JSON.stringify(event))
        }
    });
});

我原以为 ########### 会打印到控制台，但事实并非如此，因此由于某种原因没有执行侦听器函数。

如果我深入研究 ContractReceipt，就会有正确的事件数据：

{
  "transactionIndex": 0,"blockNumber": 2,"transactionHash": "0x55d118548c8200e5e6c19759d9aab56cb2e6a274186a92643de776d617d51e1a","address": "0x5FbDB2315678afecb367f032d93F642f64180aa3","topics": [
    "0x772f66a00a405709c30e7f18feadcc8f123b20c09c7260165d3eec36c9f21372"
  ],"data": "0x000000000000000000000000000000000000000000000000000000000000007b","logIndex": 0,"blockHash": "0x808e6949118509b5a9e482e84cf47921a2fcffbcd943ebbd8ce4f6671469ee01","args": [
    {
      "type": "BigNumber","hex": "0x7b"
    }
  ],"event": "TokensMinted","eventSignature": "TokensMinted(uint256)"
}