使用 Chai 和 Mocha 测试

(从 Remix IDE v0.22.0 起开始支持)

Remix支持使用断言库 Chai 和测试框架Mocha在JavaScript中对您的文件进行测试。

Chai是一个用于Node.js和浏览器的BDD / TDD断言库，可以与任何JavaScript测试框架愉快地配对使用。

Mocha是一个功能丰富的JavaScript测试框架，在Node.js和浏览器上运行，使异步测试变得简单而有趣。

编写测试

在您的项目工作区创建一个 js 文件。最好将其创建在 scripts 文件夹中。我们给它命名为 sample.test.js。

在该文件中编写您的测试代码。以下是一个示例：

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

describe("Sample", function () {
  it("Sample tests with mocha and chai", async function () {
    var foo = 'bar'
    var beverages = { tea: [ 'chai', 'matcha', 'oolong' ] };
    expect(foo).to.be.a('string');
    expect(foo).to.equal('bar');
    expect(foo).to.have.lengthOf(3);
    expect(beverages).to.have.property('tea').with.lengthOf(3);
  });
});

运行测试

完成编写测试后，在文件浏览器插件中右键单击文件名。它将显示一些选项，包括运行选项。此运行选项用于运行JS脚本。

点击 “Run” ，会执行测试，结果将显示在终端上。

测试一个合约

同样，可以编写单元测试来测试智能合约的功能。一个测试默认的1_Storage.sol合约的示例可能如下：

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

describe("Storage", function () {
  it("test initial value", async function () {
    // Make sure contract is compiled and artifacts are generated
    const metadata = JSON.parse(await remix.call('fileManager', 'getFile', 'contracts/artifacts/Storage.json'))
    const signer = (new ethers.providers.Web3Provider(web3Provider)).getSigner()
    let Storage = new ethers.ContractFactory(metadata.abi, metadata.data.bytecode.object, signer);
    let storage = await Storage.deploy();
    console.log('storage contract Address: ' + storage.address);
    await storage.deployed()
    expect((await storage.retrieve()).toNumber()).to.equal(0);
  });

  it("test updating and retrieving updated value", async function () {
    const metadata = JSON.parse(await remix.call('fileManager', 'getFile', 'contracts/artifacts/Storage.json'))
    const signer = (new ethers.providers.Web3Provider(web3Provider)).getSigner()
    let Storage = new ethers.ContractFactory(metadata.abi, metadata.data.bytecode.object, signer);
    let storage = await Storage.deploy();
    await storage.deployed()
    const setValue = await storage.store(56);
    await setValue.wait();
    expect((await storage.retrieve()).toNumber()).to.equal(56);
  });

  it("fail test updating and retrieving updated value", async function () {
    const metadata = JSON.parse(await remix.call('fileManager', 'getFile', 'contracts/artifacts/Storage.json'))
    const signer = (new ethers.providers.Web3Provider(web3Provider)).getSigner()
    let Storage = new ethers.ContractFactory(metadata.abi, metadata.data.bytecode.object, signer);
    let storage = await Storage.deploy();
    await storage.deployed()
    const setValue = await storage.store(56);
    await setValue.wait();
    expect((await storage.retrieve()).toNumber()).to.equal(55);
  });
});

结果为：

调试测试交易

要在测试中调试交易，请打印交易哈希并将其输入到Remix Debugger插件。

支持 Hardhat-ethers

Remix 还支持 Hardhat 框架的 hardhat-ethers方法。该插件下可用的方法有：

interface Libraries {
  [libraryName: string]: string;
}

interface FactoryOptions {
  signer?: ethers.Signer;
  libraries?: Libraries;
}

function getContractFactory(name: string, signer?: ethers.Signer): Promise<ethers.ContractFactory>;

function getContractFactory(name: string, factoryOptions: FactoryOptions): Promise<ethers.ContractFactory>;

function getContractFactory(abi: any[], bytecode: ethers.utils.BytesLike, signer?: ethers.Signer): Promise<ethers.ContractFactory>;

function getContractAt(name: string, address: string, signer?: ethers.Signer): Promise<ethers.Contract>;

function getContractAt(abi: any[], address: string, signer?: ethers.Signer): Promise<ethers.Contract>;

function getSigners() => Promise<ethers.Signer[]>;

function getSigner(address: string) => Promise<ethers.Signer>;

function getContractFactoryFromArtifact(artifact: Artifact, signer?: ethers.Signer): Promise<ethers.ContractFactory>;

function getContractFactoryFromArtifact(artifact: Artifact, factoryOptions: FactoryOptions): Promise<ethers.ContractFactory>;

function getContractAtFromArtifact(artifact: Artifact, address: string, signer?: ethers.Signer): Promise<ethers.Contract>;

通过这个，可以使用Remix轻松地运行Hardhat项目的测试。

例如，使用此插件方法测试Storage合约可以如下：

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

describe("Storage", function () {
  it("test initial value", async function () {
    const Storage = await ethers.getContractFactory("Storage");
    const storage = await Storage.deploy();
    await storage.deployed();
    console.log('storage deployed at:'+ storage.address)
    expect((await storage.retrieve()).toNumber()).to.equal(0);
  });
   it("test updating and retrieving updated value", async function () {
    const Storage = await ethers.getContractFactory("Storage");
    const storage = await Storage.deploy();
    await storage.deployed();
    const storage2 = await ethers.getContractAt("Storage", storage.address);
    const setValue = await storage2.store(56);
    await setValue.wait();
    expect((await storage2.retrieve()).toNumber()).to.equal(56);
  });
});

结果为：