如何在 Cucumber-js 中使用 Puppeteer 和 Headless Chrome

Question

我正在尝试使用 cucumber-js 进行 BDD，并使用 Headless Chrome 和 puppeteer 驱动浏览器测试。

使用来自 cucumber node example and headless chrome, I get the following errors, the entire code base is avaliable here: github repo 的文档。

错误：

TypeError: this.browser.newPage 不是函数
类型错误：this.browser.close 不是函数

// features/support/world.js

const puppeteer = require('puppeteer');
var {defineSupportCode} = require('cucumber');

function CustomWorld() {
  this.browser = puppeteer.launch();  
}

defineSupportCode(function({setWorldConstructor}) {
  setWorldConstructor(CustomWorld)
})

// features/step_definitions/hooks.js

const puppeteer = require('puppeteer');
var {defineSupportCode} = require('cucumber');

defineSupportCode(function({After}) {
  After(function() {
    return this.browser.close();
  });
});

// features/step_definitions/browser_steps.js

const puppeteer = require('puppeteer');
var { defineSupportCode } = require('cucumber');

defineSupportCode(function ({ Given, When, Then }) {
    Given('I am on the Cucumber.js GitHub repository', function (callback) {
        const page = this.browser.newPage();
        return page.goto('https://github.com/cucumber/cucumber-js/tree/master');
    });

    When('I click on {string}', function (string, callback) {
        // Write code here that turns the phrase above into concrete actions
        callback(null, 'pending');
    });

    Then('I should see {string}', function (string, callback) {
        // Write code here that turns the phrase above into concrete actions
        callback(null, 'pending');
    });
});

Answer 1

puppeteer 是完全异步的，所以你必须等待它初始化后才能使用 this.browser。

但是setWorldConstructor是sync函数，所以你不能在那里等。在我的示例中，我使用了 Before hook

我的例子： https://gist.github.com/dmitrika/7dee618842c00fbc35418b901735656b

Answer 2

Cucumber 已更新。这就是我用 Cucumber 实现异步人偶设置的方式。要点 here

const { BeforeAll, Before, AfterAll, After } = require('cucumber');
const puppeteer = require('puppeteer');

Before(async function() {
  const browser = await puppeteer.launch({ headless: false, slowMo: 50 });
  const page = await browser.newPage();
  this.browser = browser;
  this.page = page;
})

After(async function() {
  // Teardown browser
  if (this.browser) {
    await this.browser.close();
  }
  // Cleanup DB
})

Answer 3

我们创建了 puppeteer-cucumber-js 来简化 Puppeteer 和 Cucumber 的使用：

运行 npm install puppeteer-cucumber-js
在项目的根目录中创建一个 features 文件夹
使用您的 Given, When, Then 语句添加一个 feature-name.feature 文件
创建 features/step-definitions 文件夹
为每个功能步骤添加 JavaScript 个步骤
运行测试 node ./node_modules/puppeteer-cucumber-js/index.js --headless

GitHub

上带有工作示例的源代码

如何在 Cucumber-js 中使用 Puppeteer 和 Headless Chrome

How to use Puppeteer and Headless Chrome with Cucumber-js

javascript

cucumber

cucumberjs

google-chrome-headless

puppeteer