javascript - 类型错误 : Cannot read property 'language' of undefined

Question

我正在尝试运行 __test__ 中的 react native 提供的 App-test.js 文件，即

import 'react-native';
import React from 'react';
import App from '../src/app';

// Note: test renderer must be required after react-native.
import renderer from 'react-test-renderer';

it('renders correctly', () => {
  renderer.create(<App />);
});

开玩笑包.json 看起来像这样

...
  "jest": {
    "preset": "react-native",
    "setupFiles": [
      "<rootDir>/node_modules/react-native-gesture-handler/jestSetup.js"
    ],
    "transformIgnorePatterns": [
      "node_modules/(?!react-native)/"
    ],
    "globals": {
      "__DEV__": true
    },
    "testEnvironment": "node"
  }
...

我正在使用包 react 本地化 这在应用程序中运行良好，但在运行 jest 时出错，即:

__tests__/App-test.js
  ● Test suite failed to run

    TypeError: Cannot read property 'language' of undefined

       5 | import fr from './fr';
       6 | 
    >  7 | let localize = new LocalizedStrings({
         |                ^
       8 |     en: en,
       9 |     fr: fr
      10 | });

      at Object.customLanguageInterface (node_modules/react-native-localization/lib/LocalizedStrings.js:49:23)
      at LocalizedStrings.call (node_modules/localized-strings/lib/LocalizedStrings.js:67:42)
      at new LocalizedStrings (node_modules/react-native-localization/lib/LocalizedStrings.js:63:117)
      at Object.<anonymous> (src/common/language/localizeController.js:7:16)
      at Object.<anonymous> (src/containers/auth/launchScreen.js:25:1)

  console.error node_modules/fbjs/lib/warning.js:30

本地化 Controller .js 是

import LocalizedStrings from 'react-native-localization';

import en from './en';
import fr from './fr';

let localize = new LocalizedStrings({
    en: en,
    fr: fr
});

export default localize;

在launchScreen中像这样使用它

import localize from '@common/language/localizeController';

...

<Text style={styles.titleText}>{localize.Title}</Text>

...

如此本地化 用于所有组件，我无法测试任何组件。

Answer 1

创建 jest-setup.js 文件(如果不存在)并在其中添加以下行

import { NativeModules } from 'react-native';

NativeModules.ReactLocalization = {
    language: 'en',
};

现在添加到 包.json ，现在 package.json 中的 JEST 看起来像这样。

...
"jest": {
    "preset": "react-native",
    "transformIgnorePatterns": [
      "node_modules/(?!react-native|react)/"
    ],
    "setupFiles": [
      "<rootDir>/jest-setup.js"
    ],
    "globals": {
      "__DEV__": true
    },
    "testEnvironment": "node"
  }
...

现在这个错误消失了。
Source