使用Jasmine和TypeScript测试react-native时找不到模块'View' [英] Cannot find module 'View' while testing react-native with Jasmine and TypeScript

问题描述

我正在尝试使用Jasmine测试一个简单(空")的本机组件.但是当我尝试访问任何react-native组件时遇到错误...

I'm trying to test a simple ("empty") react-native component using Jasmine. But I'm getting an error when I try to access any react-native component...

在我的配置文件(jasmine.json)中，我有:

In my configuration file (jasmine.json) I have:

{
  "spec_dir": ".",
  "spec_files": [
    "src/*.spec.tsx"
  ],
  "helpers": [
    "./node_modules/ts-node/register.js"
  ]
}

我的package.json

My package.json

"react": "16.0.0-alpha.12",
"react-native": "0.45.1",

"jasmine": "^2.6.0",
"ts-node": "^3.3.0",

我在package.json上的测试脚本

My test script on package.json

"test": "jasmine --config=jasmine.json"

我的测试

import * as React from 'react';
import App from './App';

import { createRenderer } from 'react-test-renderer/shallow';
import { StyleSheet, Text, View } from 'react-native';

console.log('View', View); // error

错误:

Error: Cannot find module 'View'
    at Function.Module._resolveFilename (module.js:470:15)
    at Function.Module._load (module.js:418:25)
    at Module.require (module.js:498:17)
    at require (internal/module.js:20:19)
    at Object.get View [as View] (...\expo-ts-example\node_modules\react-native\Libraries\react-native\react-native-implementation.js:56:23)
    at Object.<anonymous> (...\expo-ts-example\src\App.spec.tsx:7:21)
    at Module._compile (module.js:571:32)
    at Module.m._compile (...\expo-ts-example\node_modules\ts-node\src\index.ts:392:23)
    at Module._extensions..js (module.js:580:10)
    at Object.require.extensions.(anonymous function) [as .tsx] (...\expo-ts-example\node_modules\ts-node\src\index.ts:395:12)

在我的组件上进行的任何测试均失败，因为它使用的根"元素是View.

Any tests on my component fail because the "root" element it uses is a View.

为什么会出现此错误?有什么方法可以用Jasmine代替Jest进行测试吗?

Why do I get this error? Is there any way I can use Jasmine to test instead of Jest?

推荐答案

View是本机元素，因此，当您在本机环境之外运行Jasmine环境时，它不可用.

View is a native element, and is therefore not available to the Jasmine environment when you run it outside of a native environment.

这通常可以通过模拟整个react-native组件API来解决(例如，使用类似酶之类的浅呈现方法>.两者都可以与任何测试框架一起使用.

This is usually solve by either mocking the entire react-native component API (For example by using something like react-native-mock), or by using a shallow rendering approach such as Enzyme. Both will work with any testing framework.

那是说，在写了一些测试之后，我发现如果我重构代码以使函数中的所有逻辑都与本机无关，那么端到端测试将覆盖相互作用，那么组件级测试就变得多余了，几乎没有价值.

That said, After writing these kind of tests for a bit, I found that if I refactor the code to have all of the logic in functions that have nothing to do with react-native, and end-to-end tests cover the interaction, then the component-level tests become redundant and give very little value.

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