javascript - 引用错误 : You are trying to `import` a file after the Jest environment has been torn down

Question

我有一个组件使用来自 React Native 的 Animated 组件。我开始编写一个测试用例来模拟组件的 onPress，它调用一个函数，其中包含 Animated.timing 和 setState。

运行 jest 工作正常，但测试永远不会停止运行，而且我之前编写的一个不相关的测试用例现在似乎从未通过(之前通过)。

运行 jest --watch，我得到这个错误:

ReferenceError: You are trying to `import` a file after the Jest environment has been torn down.

      at Function.bezier (node_modules/react-native/Libraries/Animated/src/Easing.js:113:21)
      at ease (node_modules/react-native/Libraries/Animated/src/Easing.js:34:24)
      at TimingAnimation._easing (node_modules/react-native/Libraries/Animated/src/Easing.js:133:18)
      at TimingAnimation.onUpdate (node_modules/react-native/Libraries/Animated/src/animations/TimingAnimation.js:107:45)

 RUNS  src/__tests__/SlideDownMenu.test.js

/home/nrion/Desktop/mobile-ui/PriceInsight_app/node_modules/react-native/Libraries/Animated/src/Easing.js:114
      return _bezier(x1, y1, x2, y2);
             ^
TypeError: _bezier is not a function
    at Function.bezier (/home/nrion/Desktop/mobile-ui/PriceInsight_app/node_modules/react-native/Libraries/Animated/src/Easing.js:224:12)
    at ease (/home/nrion/Desktop/mobile-ui/PriceInsight_app/node_modules/react-native/Libraries/Animated/src/Easing.js:94:21)
    at TimingAnimation._easing (/home/nrion/Desktop/mobile-ui/PriceInsight_app/node_modules/react-native/Libraries/Animated/src/Easing.js:255:16)
    at TimingAnimation.onUpdate (/home/nrion/Desktop/mobile-ui/PriceInsight_app/node_modules/react-native/Libraries/Animated/src/animations/TimingAnimation.js:138:14)
    at ontimeout (timers.js:386:11)
    at tryOnTimeout (timers.js:250:5)
    at Timer.listOnTimeout (timers.js:214:5)

链接到回复

https://repl.it/repls/PartialGrimyMetadata

环境:

• 操作系统:Linux 4.14
• 节点:6.14.2
• yarn :1.7.0
• npm:3.10.10
• 守望者:未找到
• Xcode:不适用
• Android Studio:未找到

Answer 1

好的，找到解决方案。

应该使用jest.useFakeTimers()

注意:将上面的代码放在测试文件中的 import 部分之后。