使用 babel 转译 javascript 代码的问题答案

【问题标题】：Issue with transpiling javascript code with babel使用 babel 转译 javascript 代码的问题
【发布时间】：2019-01-11 23:02:39
【问题描述】：

由于 babel 无法正确转换代码的问题，所有测试都失败了。

以下是来自控制台的错误。

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://jestjs.io/docs/en/configuration.html
  Details:
    13 |
    14 | 
  > 15 | import type { CreateUserInput, CreateSlackTeamInput } from "graphql-types";

下面是我的 Babel 配置。

{
  "presets": [
    "es2015"
  ]
}

【问题讨论】：

标签： testing jestjs babeljs

【解决方案1】：

我能够在本地重现您的问题并通过将 babel-preset-flow 添加到 devDependencies 并将预设添加到 .babelrc 来解决它。它失败的原因是import type 语法未包含在es2015 babel 预设中。

更新后的.babelrc 文件将如下所示：

{ "presets": [ "es2015", "flow" ] }

【讨论】：