具有模块分辨率的打字稿的最佳设置

Question

该项目正在使用ReactJS，Typescript，Webpack和Jest。为了实现模块分辨率（以尽量减少导入），我们进行了以下更改：

TSConfig.js:

"compilerOptions": { "baseUrl": "src",}

Webpack.config.js

alias: {
  Common: path.resolve(__dirname, 'src/Common/'),
},

代码运行正常，但是Jest测试开始失败并显示错误：

Cannot find module 'Common/js/utils' from 'MyContact.ts'

这是因为，Jest尚不知道如何将Common解析为Src / common，并且不查看node_module。为了解决这个问题，进行了以下更改：

jestConfig.js

moduleNameMapper: {"Common": "<rootDir>/src/Common"}

这似乎已解决，但是我还有另一个问题[这就是为什么我在这里：）]

偶然遇到意外令牌

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:

C:\Users\ua\Project\develop\src\Common\index.ts:1
({"Object.<anonymous>":function(module,exports,require,__dirname,__filename,global,jest){export * from './Acc'
                                                                                         ^^^^^^

SyntaxError: Unexpected token export

  at ScriptTransformer._transformAndBuildScript (node_modules/@jest/transform/build/ScriptTransformer.js:537:17)
  at ScriptTransformer.transform (node_modules/@jest/transform/build/ScriptTransformer.js:579:25)

这里是完整的jest.config.js文件：

module.exports = {
  verbose: false,
  roots: ["<rootDir>/src"],
  transform: {
    "^.+\\.tsx?$": "ts-jest",
  },
  globals: {
    'ts-jest': {
      diagnostics: false
    }
  },
  moduleNameMapper: {
    "\\.(jpg|jpeg|png|gif|eot|otf|webp|svg|ttf|woff|woff2|mp4|webm|wav|mp3|m4a|aac|oga)$":
      "<rootDir>/__mocks__/fileMock.js",
    "\\.(css|less|pcss)$": "<rootDir>/__mocks__/styleMock.js",
    "Common": "<rootDir>/src/Common",
  },
  snapshotSerializers: ["enzyme-to-json/serializer"],
  setupFilesAfterEnv: ["<rootDir>/setupEnzyme.ts"],
  testMatch: [ "**/__tests__/**/*.test.[jt]s?(x)", "**/?(*.)+(spec|test).[jt]s?(x)"],
  collectCoverageFrom: ["**/*.{ts,tsx}", "!**/node_modules/**", "!**/vendor/**"]
};

tsconfig.js：

{
  "compileOnSave": false,
  "compilerOptions": {
    "baseUrl": "src",
    "typeRoots": [
      "./node_modules/@types",
      "./custom_typings"
    ],
    "outDir": "build",
    "module": "commonjs",
    "skipLibCheck": true,
    "moduleResolution": "node",
    "removeComments": true,
    "target": "es5",
    "sourceMap": true,
    "lib": [ "dom", "es2015", "es2017", "esnext" ],
    "noEmit": false,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "noImplicitAny": false,
    "allowUnusedLabels": false,
    "jsx": "react",
    "allowJs": true,
    "isolatedModules": false,
    "strictNullChecks": false,
    "noEmitHelpers": false,
    "allowSyntheticDefaultImports": true
  },
  "typeRoots": [
    "./node_modules/@types",
    "./custom_typings"
  ],
  "exclude":[
    "./node_modules"
  ],
  "include": [
    "src/*",
    "custom_typings"
  ]
}

Answer 1

默认情况下，像babel一样无法解析打字稿测试文件，因此请安装npm install ts-jest babel-jest --save-dev，然后在jest.config.js文件中的config下面添加。

  transform: {
    '^.+\\.jsx?$': require.resolve('babel-jest'),
    '^.+\\.tsx?$': 'ts-jest',
  }

Answer 2

好，所以我能够通过将这一行添加到jest.config.js中来解决模块分辨率问题>

moduleDirectories: ["node_modules", "src"],