Question

我正在测试我的React + TypeScript组件，但是我收到了这个奇怪的消息，我尝试了所有内容，但没有找到任何有用的资源，这是TypeScript错误还是其他原因，老实说，我在这里头晕目眩，所以遇到了一个问题：

Jest encountered an unexpected token

    This usually means that you are trying to import a file which Jest cannot parse, e.g. it's not plain JavaScript.

    By default, if Jest sees a Babel config, it will use that to transform your files, ignoring "node_modules".

    Here's what you can do:
     • To have some of your "node_modules" files transformed, you can specify a custom "transformIgnorePatterns" in your config.
     • If you need a custom transformation specify a "transform" option in your config.
     • If you simply want to mock your non-JS modules (e.g. binary assets) you can stub them out with the "moduleNameMapper" config option.

    You'll find more details and examples of these config options in the docs:
    https://jestjs.io/docs/en/configuration.html

    Details:

    /home/dr/code/npmpackage/darkmode/src/style.module.css:1
    ({"Object.<anonymous>":function(module,exports,require,__dirname,__filename,global,jest){.switch {
                                                                                             ^

    SyntaxError: Unexpected token '.'

      1 | import * as React from 'react'
      2 | // import 'learning-npm-package/dist/index.css'
    > 3 | import classes from './style.module.css'

我当前在React Project中使用的软件包如下：

"peerDependencies": {
    "react": "^16.0.0"
  },
  "devDependencies": {
    "@testing-library/jest-dom": "^4.2.4",
    "@testing-library/react": "^9.5.0",
    "@testing-library/user-event": "^7.2.1",
    "@types/jest": "^25.1.4",
    "@types/node": "^12.12.38",
    "@types/react": "^16.9.27",
    "@types/react-dom": "^16.9.7",
    "@typescript-eslint/eslint-plugin": "^2.26.0",
    "@typescript-eslint/parser": "^2.26.0",
    "babel-eslint": "^10.0.3",
    "cross-env": "^7.0.2",
    "enzyme-to-json": "^3.5.0",
    "eslint": "^6.8.0",
    "eslint-config-prettier": "^6.7.0",
    "eslint-config-standard": "^14.1.0",
    "eslint-config-standard-react": "^9.2.0",
    "eslint-plugin-import": "^2.18.2",
    "eslint-plugin-node": "^11.0.0",
    "eslint-plugin-prettier": "^3.1.1",
    "eslint-plugin-promise": "^4.2.1",
    "eslint-plugin-react": "^7.17.0",
    "eslint-plugin-standard": "^4.0.1",
    "gh-pages": "^2.2.0",
    "microbundle-crl": "^0.13.10",
    "npm-run-all": "^4.1.5",
    "prettier": "^2.0.4",
    "react": "^16.13.1",
    "react-dom": "^16.13.1",
    "react-scripts": "^3.4.1",
    "ts-jest": "^26.1.2",
    "typescript": "^3.7.5"
  },
  "files": [
    "dist"
  ],
  "dependencies": {
    "@types/enzyme": "^3.10.5",
    "@types/enzyme-adapter-react-16": "^1.0.6",
    "enzyme": "^3.11.0",
    "enzyme-adapter-react-16": "^1.15.2",
    "react-test-renderer": "^16.13.1"
  }

./ style.module.css：

.switch {
  display: flex;
  height: 36px;
  position: relative;
  width: 70px;
}

/** small */
.container {
  height: 26px;
  width: 50px;
}

感谢您的帮助！

Answer 1

因此，在研究找到解决方案后，我将自己回答。默认情况下，jest不知道如何处理CSS文件，因此我们需要CSS模块模拟来进行jest，为此，我们需要在Webpack和Jest之间建立桥梁，这就是moduleNameMapper扮演桥梁角色的方式，我们只需要安装identity-obj-proxy即可创建一个模拟CSS模块，该模块将返回预期的CSS className，例如<div className={classes.div}>。

让我们安装代理：

yarn add identity-obj-proxy

// NPM
npm install identity-obj-proxy

在根/而不是src的根目录jest.config.js上创建一个文件，并放置以下代码：

module.exports ={
  moduleNameMapper: {
    "\\.css$": "identity-obj-proxy",
  },
};

Resource

笑话在打字稿中遇到了意外令牌

1 个答案: