用graphql开玩笑，“插件/预设文件不允许导出对象，只能导出功能”

Question

I'm trying to write some tests with JEST and graphql but am getting the following error no matter what I have in my .test.js files (even when having no code at all in it).

Plugin/Preset files are not allowed to export objects, only functions. In /Users/oscarstein/Documents/Projekt/Biljettsystem/ticketgo/system/node_modules/babel-preset-stage-2/lib/index.js

My .babelrc file looks as follows:

{
    "presets": ["env", "stage-2"]
   }

So the error comes from me using the preset "stage-2" and when i remove it everything works fine with the tests. But since my application is built with stage-2 I was wondering if there is any workaround using both "stage-2" and getting the JEST tests to work?

---

package.json file

{
  "name": "system",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "start": "nodemon --exec babel-node index.js",
    "test": "jest"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "dependencies": {
    "apollo-server": "^2.1.0",
    "apollo-server-express": "^2.1.0",
    "bcrypt": "^3.0.2",
    "body-parser": "^1.18.3",
    "cors": "^2.8.5",
    "dotenv": "^6.1.0",
    "express": "^4.16.4",
    "graphql": "^14.0.2",
    "jest": "^24.0.0",
    "jsonwebtoken": "^8.3.0",
    "mysql2": "^1.6.4",
    "nodemailer": "^4.6.8",
    "nodemon": "^1.18.6",
    "pg": "^7.6.0",
    "sequelize": "^4.41.1",
    "stripe": "^6.22.0"
  },
  "devDependencies": {
    "@babel/core": "^7.2.2",
    "babel-cli": "^6.26.0",
    "babel-preset-env": "^1.7.0",
    "babel-preset-stage-2": "^6.24.1"
  }
}

Answer 1

Babel 7 has different preset/plugin dependencies from previous versions. The link posted by LoudNoises shows how to update the dependencies. In your case, npm i -D @babel/preset-env @babel/preset-stage-2 , and then update your .babelrc :

{
  "presets": ["@babel/env", "@babel/stage-2"]
}