无法读取未定义的属性“方向”，仅测试

Question

我刚刚将TouchableOpacity 添加到一个组件中，应用程序运行良好，但我使用react-native-testing-library 的测试无法运行：

  ● Test suite failed to run

    TypeError: Cannot read property 'Direction' of undefined

      at Object.Direction (node_modules/react-native-gesture-handler/Directions.js:3:39)
      at Object.<anonymous> (node_modules/react-native-gesture-handler/GestureHandler.js:2:1)

我刚刚用纱线删除并重新添加了react-native-gesture-handler，然后运行了pod install。同样，应用程序正在运行，但测试无法运行。

我在使用<Text onPress={() => onOptionPress(opt)} /> 而不是TouchableOpacity 时实际上得到了同样的错误。

组件：

const SelectOptions = ({ field, dismissOverlay, onOptionPress }) => {
  return (
    <Overlay
      isVisible
      overlayStyle={styles.overlay}
      height={"auto"}
      onBackdropPress={dismissOverlay}
    >
      <View>
        {field.options.map((opt, i) => (
          <TouchableOpacity
            style={styles.option}
            key={i}
            onPress={() => onOptionPress(opt)}
          >
            <Text>{opt}</Text>
          </TouchableOpacity>
        ))}
      </View>
    </Overlay>
  );
};

测试：

describe("CardFormView", () => {
  let wrapper, birthdayField;

  beforeEach(() => {
    wrapper = render(
      <React.Fragment>
        <CardFormView form={form} />
      </React.Fragment>
    );
    birthdayField = wrapper.getByText("Add a Birthday Gift Card");
  });

  const message1 =
    "...";
  const message2 =
    "...";

  it("shows the options for a birthday card when clicked", () => {
    fireEvent.press(birthdayField);
    expect(wrapper.getByText(message1)).toBeDefined();
  });

  it("sets an option when clicked", () => {
    fireEvent.press(birthdayField);
    const firstOption = wrapper.getByText(message1);
    fireEvent.press(firstOption);
    expect(wrapper.queryByText(message2)).toBeNull();
    expect(wrapper.getByText(message1)).toBeDefined();
  });
});

Answer 1

这是因为你没有嘲笑react-navigation-gesture-handler

要使用 react-navigation-gesture-handler 的模拟，您应该从 jest.config.json 或 jest.config.js 中的 node_modules 添加 jestSetup.js

setupFiles: [
  "./node_modules/react-native-gesture-handler/jestSetup.js"
]

我从以下链接中找到了一个参考，它对我有用。

https://github.com/software-mansion/react-native-gesture-handler/issues/344#issuecomment-489547513

Answer 2

对我来说，仅添加 setupFiles 不起作用。我在 package.json

的 "jest" 处添加了 setupFiles 和 transformIgnorePatterns

这里是使 gestureHandler 工作的代码，但我用 AsyncStorage 对其进行了测试，并且存储停止工作。如果您不使用 AsyncStorage，我想这段代码会很好用！

"setupFiles": [
     "./node_modules/react-native-gesture-handler/jestSetup.js"
],
"transformIgnorePatterns": [
     "/node_modules/(?!native-base)/"
]

我的参考： https://github.com/software-mansion/react-native-gesture-handler/issues/344

Answer 3

更新 package.json 并重新安装 npm 包对我有用。

"jest": {
    "preset": "react-native",
    "transformIgnorePatterns": ["node_modules/(?!(jest-)?react-native|@?react-navigation)"],
    "setupFiles": ["./node_modules/react-native-gesture-handler/jestSetup.js"]
}

Answer 4

发生这种情况是因为您必须从 react-native 模拟 NativeModules 模块。它可能发生在几个模块上，但它发生在我身上，特别是 ImagePicker、Linking 和 @react-navigation/native。这就是我模拟原生模块所做的。

/src/testSetup.ts

import {NativeModules} from 'react-native';

NativeModules.RNGestureHandlerModule= {
    attachGestureHandler: jest.fn(),
    createGestureHandler: jest.fn(),
    dropGestureHandler: jest.fn(),
    updateGestureHandler: jest.fn(),
    State: {},
    Directions: {},
},

NativeModules.ImagePickerManager = {
    showImagePicker: jest.fn(),
}

NativeModules.Linking = {
    canOpenUrl: jest.fn().mockResolvedValue(true),
    openUrl: jest.fn().mockResolvedValue(true)
}

NativeModules.Platform = {
    OS: 'iOS'
}

jest.mock('react-native/Libraries/Animated/src/NativeAnimatedHelper');
jest.mock('react-native/Libraries/Animated/src/animations/TimingAnimation');


const mockNavigation = () => {
    const mockedNavigate = jest.fn();
    const mockedAddListener = jest.fn();

    jest.mock('@react-navigation/native', () => ({ // @ts-ignore
        ...(jest.requireActual('@react-navigation/native')),
        useNavigation: () => ({
          navigate: mockedNavigate,
          addListener: mockedAddListener
        })
      }));
    
    return {mockedNavigate, mockedAddListener}
}

在你的测试中

import { fireEvent, act, render } = '@testing-library/react-native'

const {mockedNavigate, mockedAddListener} = mockNavigation()

test('Should navigate', () => {
  const { queryByText } = render(<Component />)

  fireEvent.press(getByText('View Page Button'))

  expect(mockedNavigate).toHaveBeenCalledWith('Your Page Name')
  expect(mockedAddListener).toHaveBeenCalled()
})

Answer 5

就我而言，遇到此问题时我使用的是react-native-cli。我删除了它并安装了@react-native-community/cli。它解决了所有问题！