运行Jest测试时出现意外的令牌“导入”错误?

我知道这个问题已经被问过几次了,但是我遇到的所有解决方案似乎都不适合我。我在尝试为Vue应用程序运行Jest测试时遇到以下错误。

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://facebook.github.io/jest/docs/en/configuration.html

Details:

/node_modules/vue-awesome/icons/expand.js:1
({"Object.<anonymous>":function(module,exports,require,__dirname,__filename,global,jest){import Icon from '../components/Icon.vue'
                                                                                         ^^^^^^

SyntaxError: Unexpected token import

> 17 | import 'vue-awesome/icons/expand'

.babelrc:

{
  "presets": [
    ["env", {
      "modules": false,
      "targets": {
        "browsers": ["> 1%", "last 2 versions", "not ie <= 8"]
      }
    }]
  ],
  "env": {
    "test": {
      "presets": [
        ["env", { "targets": { "node": "current" }}]
      ]
    }
  }
}

package.json中的jest配置:

"jest": {
  "moduleFileExtensions": [
    "js",
    "vue"
  ],
  "moduleNameMapper": {
    "^@/(.*)$": "<rootDir>/src/$1"
  },
  "transform": {
    "^.+\\.js$": "<rootDir>/node_modules/babel-jest",
    ".*\\.(vue)$": "<rootDir>/node_modules/vue-jest"
  },
  "snapshotSerializers": [
    "<rootDir>/node_modules/jest-serializer-vue"
  ],
  "moduleDirectories": [
    "node_modules",
    "src"
  ]
}

似乎脚本中的初始导入正在为测试安装的Vue组件正在运行,但是import Icon from '../components/Icon.vue无法识别模块本身(内的导入

我该如何解决?

西里宝儿Harry2020/03/13 17:12:36

如果在更新到更新的Jest版本后遇到此问题,请尝试清除Jest的内部缓存:

jest --clearCache
西门十三LEY2020/03/13 17:12:36

您只需要确保vue-awesome将被jest转换,因此将以下内容添加到jest配置中:

transformIgnorePatterns: ["/node_modules/(?!vue-awesome)"],

这意味着:“忽略node_modules中的所有内容,除了vue-awesome

另外,这里还有可能导致此错误的其他问题的详尽列表:https : //github.com/facebook/jest/issues/2081