从Protractor迁移

迁移原则​

• 无需使用"webdriver-manager" / Selenium。
• Protractor的ElementFinder ⇄ Playwright Test Locator
• Protractor的waitForAngular ⇄ Playwright Test 自动等待
• 在Playwright Test中别忘了使用await

速查表​

示例​

Protractor:

describe('angularjs homepage todo list', function() {
  it('should add a todo', function() {
    browser.get('https://angularjs.org');

    element(by.model('todoList.todoText')).sendKeys('first test');
    element(by.css('[value="add"]')).click();

    const todoList = element.all(by.repeater('todo in todoList.todos'));
    expect(todoList.count()).toEqual(3);
    expect(todoList.get(2).getText()).toEqual('first test');

    // You wrote your first test, cross it off the list
    todoList.get(2).element(by.css('input')).click();
    const completedAmount = element.all(by.css('.done-true'));
    expect(completedAmount.count()).toEqual(2);
  });
});

逐行迁移到Playwright Test:

const { test, expect } = require('@playwright/test'); // 1

test.describe('angularjs homepage todo list', () => {
  test('should add a todo', async ({ page }) => { // 2, 3
    await page.goto('https://angularjs.org'); // 4

    await page.locator('[ng-model="todoList.todoText"]').fill('first test');
    await page.locator('[value="add"]').click();

    const todoList = page.locator('[ng-repeat="todo in todoList.todos"]'); // 5
    await expect(todoList).toHaveCount(3);
    await expect(todoList.nth(2)).toHaveText('first test', {
      useInnerText: true,
    });

    // You wrote your first test, cross it off the list
    await todoList.nth(2).getByRole('textbox').click();
    const completedAmount = page.locator('.done-true');
    await expect(completedAmount).toHaveCount(2);
  });
});

迁移亮点（请参阅Playwright Test代码片段中的内联注释）：

1. 每个Playwright Test文件都明确导入了test和expect函数
2. 测试函数被标记为async
3. Playwright Test 提供了一个 page 作为其参数之一。这是 Playwright Test 中众多实用夹具中的一个。
4. 几乎所有Playwright调用都以await作为前缀
5. 使用page.locator()创建定位器是少数同步方法之一。

填充waitForAngular的polyfill实现​

Playwright Test内置了自动等待功能，使得在一般情况下不再需要protractor的waitForAngular。

不过，在某些边缘情况下它可能会派上用场。以下是如何在Playwright Test中填充waitForAngular函数：

1. 确保你的package.json中已安装protractor

2. Polyfill function

   async function waitForAngular(page) {
     const clientSideScripts = require('protractor/built/clientsidescripts.js');
   
     async function executeScriptAsync(page, script, ...scriptArgs) {
       await page.evaluate(`
         new Promise((resolve, reject) => {
           const callback = (errMessage) => {
             if (errMessage)
               reject(new Error(errMessage));
             else
               resolve();
           };
           (function() {${script}}).apply(null, [...${JSON.stringify(scriptArgs)}, callback]);
         })
       `);
     }
   
     await executeScriptAsync(page, clientSideScripts.waitForAngular, '');
   }
   

   If you don't want to keep a version protractor around, you can also use this simpler approach using this function (only works for Angular 2+):

   async function waitForAngular(page) {
     await page.evaluate(async () => {
       // @ts-expect-error
       if (window.getAllAngularTestabilities) {
         // @ts-expect-error
         await Promise.all(window.getAllAngularTestabilities().map(whenStable));
         // @ts-expect-error
         async function whenStable(testability) {
           return new Promise(res => testability.whenStable(res));
         }
       }
     });
   }
   

3. Polyfill 用法

   const page = await context.newPage();
   await page.goto('https://example.org');
   await waitForAngular(page);
   

Playwright Test 超级能力​

一旦你开始使用Playwright Test，你将获得很多功能！

• 完全零配置的TypeScript支持
• 在所有主流操作系统（Windows、macOS、Ubuntu）上运行所有网页引擎（Chrome、Firefox、Safari）的测试
• 全面支持多源站、(i)frames、标签页和上下文
• 在多个浏览器中并行运行测试
• 内置测试artifact collection

你还将获得这些✨超棒工具✨，它们都随Playwright Test捆绑提供：

• Playwright Inspector
• Playwright 测试代码生成
• Playwright Tracing 用于事后调试

延伸阅读​

了解更多关于Playwright测试运行器的信息：

• 入门指南
• Fixtures
• 定位器
• 断言
• 自动等待