angular-testing-library：getByRole 查询仅适用于 hidden: true 选项

Posted 2023-03-08

【中文标题】angular-testing-library：getByRole 查询仅适用于 hidden: true 选项

【英文标题】：angular-testing-library: getByRole query works only with hidden: true option

【发布时间】：2020-11-20 18:02:27

【问题描述】：

我只是在试用这个库，似乎无法通过他们的 ARIA 角色访问元素。

我使用 angular 10.0.6、jest 26.2.1 以及 jest-preset-angular 8.2.1 和 @testing-library/angular 10.0.1。我相信已经按照https://www.npmjs.com/package/jest-preset-angular 和https://testing-library.com/docs/angular-testing-library/intro 中的描述设置了项目

这是我要测试的组件：

<h1>title</h1>
<img src="../assets/chuck-norris-logo.jpg" >
<p role="status">jokeText</p>
<button (click)="refreshJoke()">Refresh</button>

以及一些测试的相关部分：

test('refreshes joke on click', async () => 
    const component = await render(AppComponent);

    const button = component.getByRole('button');
    fireEvent.click(button);
  );

但是，我收到一条错误消息，提示找不到该角色。

TestingLibraryElementError: Unable to find an accessible element with the role "button"

There are no accessible roles. But there might be some inaccessible roles. If you wish to access them, then set the `hidden` option to `true`. Learn more about this here: https://testing-library.com/docs/dom-testing-library/api-queries#byrole

<div
  id="root1"
  ng-version="10.0.6"
>
  <h1>
    Chuck Norris
  </h1>
  <img
    
    src="../assets/chuck-norris-logo.jpg"
  />
  <p
    role="status"
  >
    Chuck Norris uses canvas in IE.
  </p>
  <button>
    Refresh
  </button>
</div>

我可以通过将hidden 选项设置为true 来规避这种情况。

import configure from '@testing-library/dom';

configure(
  defaultHidden: true
);

由于我尝试使用的其他查询功能（例如 getByText 和 getByTestId）工作正常，而且我从未遇到过类似的 react 问题，我想我以某种方式搞砸了我的配置。

这是我完整的 package.json

  "name": "chuck-norris-ng",
  "version": "0.0.0",
  "scripts": 
    "ng": "ng",
    "start": "ng serve",
    "build": "ng build",
    "test": "jest",
    "test:watch": "jest --watch",
    "lint": "ng lint",
    "e2e": "ng e2e"
  ,
  "private": true,
  "dependencies": 
    "@angular/animations": "~10.0.6",
    "@angular/common": "~10.0.6",
    "@angular/compiler": "~10.0.6",
    "@angular/core": "~10.0.6",
    "@angular/forms": "~10.0.6",
    "@angular/platform-browser": "~10.0.6",
    "@angular/platform-browser-dynamic": "~10.0.6",
    "@angular/router": "~10.0.6",
    "rxjs": "~6.6.0",
    "tslib": "^2.0.0",
    "zone.js": "~0.10.2"
  ,
  "devDependencies": 
    "@angular-devkit/build-angular": "~0.1000.4",
    "@angular/cli": "~10.0.4",
    "@angular/compiler-cli": "~10.0.6",
    "@testing-library/angular": "^10.0.1",
    "@testing-library/jest-dom": "^5.11.2",
    "@types/jest": "^26.0.7",
    "@types/node": "^12.11.1",
    "codelyzer": "^6.0.0",
    "jest": "^26.2.1",
    "jest-preset-angular": "^8.2.1",
    "protractor": "~7.0.0",
    "ts-node": "~8.3.0",
    "tslint": "~6.1.0",
    "typescript": "~3.9.7"
  ,
  "jest": 
    "preset": "jest-preset-angular",
    "setupFilesAfterEnv": [
      "<rootDir>/src/setup-jest.ts"
    ]
  

我已将我的 repo 上传到 GitHub。我做错了什么？

【参考方案1】：

我遇到了同样的问题，我通过删除 https://www.npmjs.com/package/jest-preset-angular#usage 的“使用”部分中引用的一部分开玩笑的浏览器模拟来解决我的问题：

我从 jest-global-mocks.ts 文件中删除了以下内容：

Object.defineProperty(window, 'getComputedStyle', 
   value: () => 
      return 
         display: 'none',
         appearance: ['-webkit-appearance'],
      ;
   ,
);

我在https://www.amadousall.com/how-to-set-up-angular-unit-testing-with-jest/ 之类的文章中看到了类似的全局模拟 https://www.npmjs.com/package/@testing-library/jest-dom）。也许其他人可以帮助更详细地解释用例，但现在我很高兴我可以再次使用 getByRole()。

【讨论】：

谢谢！我可以确认它完美无缺！

仅供参考，在jest-present-angular提交了一个问题