未找到 Jest 配置 setupFilesAfterEnv 选项答案

【问题标题】：Jest configuration setupFilesAfterEnv option was not found未找到 Jest 配置 setupFilesAfterEnv 选项
【发布时间】：2021-03-14 08:08:53
【问题描述】：

我正在尝试让 Jest 再次用于 1 年前开发但未维护的项目。

setupFilesAfterEnv或transform的路径有错误。

我在运行“yarn test”时遇到的错误

$ jest __testsv2__ --config=./jest.config.js
● Validation Error:

Module <rootDir>/jest/setup.js in the setupFilesAfterEnv option was not found.
       <rootDir> is: /Users/alain/dev/ddf/release

Configuration Documentation:
https://jestjs.io/docs/configuration.html

error Command failed with exit code 1.

我的文件系统，在 /Users/alain/dev/ddf/release/ 我有

  babel.config.js
  jest.config.js
  /jest
    /setup
    setup.js ( so  full path is : /Users/alain/dev/ddf/release/jest/setup.js ) 
    staticFileAssetTransform.js ( so full path is : /Users/alain/dev/ddf/release/jest/staticFileAssetTransform.js )

我的 package.json

{ ...
 "scripts": {
      "test": "jest __testsv2__ --config=./jest.config.js"
      ...
  }
}

babel.config.js

module.exports = function(api) {
   api.cache(false);
   const presets = ['@babel/preset-env', '@babel/preset-react'];    
   const plugins = [['@babel/proposal-object-rest-spread'],];

   return {
     presets,    plugins,   sourceMaps: "inline",
     ignore: [(process.env.NODE_ENV !== 'test' ?  "**/*.test.js" : null)    ].filter(n => n)
   };
 };

jest.config.js

 module.exports = {
  resolver: 'browser-resolve',
  clearMocks: true,
  moduleNameMapper: {    '\\.(css|less|styl|md)$': 'identity-obj-proxy'    },
  // A list of paths to modules that run some code to configure or set up the testing framework before each test
  // setupFilesAfterEnv: ['./jest/setup.js'], // don't work too
  setupFilesAfterEnv: ['<rootDir>/jest/setup.js'], 


  // An array of regexp pattern strings that are matched against all test paths, matched tests are skipped
  testPathIgnorePatterns: ['/node_modules/', '/__gql_mocks__/'],

  // A map from regular expressions to paths to transformers
  transform: {
    '^.+\\.js$': './jest/babelRootModeUpwardTransform.js',
    '\\.(jpg|jpeg|png|gif|eot|otf|webp|svg|ttf|woff|woff2|mp4|webm|wav|mp3|m4a|aac|oga)$': '<rootDir>/jest/staticFileAssetTransform.js',
  },
};

【问题讨论】：

尝试 cat /Users/alain/dev/ddf/release/jest/setup.js 检查文件是否真的存在

标签： path jestjs

【解决方案1】：

Module <rootDir>/jest.setup.js in the setupFilesAfterEnv option was not found. 错误很明显。

为什么会出现此错误是因为在您的项目的root directory 中找不到jest.setup.js。

修复：

从jest.config.js 中删除setupFilesAfterEnv。

或者：

在您的项目的root directory 中创建一个jest.setup.js，并在文件中的每个测试之前设置一个测试框架。

即import '@testing-library/jest-dom/extend-expect' 在jest.setup.js 文件中。

【讨论】：