Jest encountered an unexpected token

For anyone using create-react-app, only certain jest configurations can be changed in package.json when using create-react-app.

I have issues with Jest picking up an internal library, Jest would display 'unexpected token' errors wherever I had my imports from this library.

To solve this, you can change your test script to the below: "test": "react-scripts test --transformIgnorePatterns 'node_modules/(?!(<your-package-goes-here>)/)'",

Add this in your package.json jest config.

"transform": {
      "\\.js$": "<rootDir>/node_modules/babel-jest"
    },

Let me know if the issue still persists.

I also encountered the same error while setting up Jest in my React app created using Webpack. I had to add @babel/preset-env and it was fixed. I have also written a blog article about the same.

npm i -D @babel/preset-env

And then add this in "presets" in .babelrc file. E.g.

{ 
  "presets": ["@babel/react", "@babel/env"]
}

https://medium.com/@shubhgupta147/how-i-solved-issues-while-setting-up-jest-and-enzyme-in-a-react-app-created-using-webpack-7e321647f080?sk=f3af93732228d60ccb24b47ef48d7062

for anyone who struggled with this issue and non of the above answers worked for him/her.

after about a long time of searching, I reached for this solution

edit your jest.config.js to add transformIgnorePatterns

//jest.config.js

module.exports = {
    preset: 'ts-jest',
    testEnvironment: 'jsdom',
    testMatch: ["**/__tests__/**/*.ts?(x)", "**/?(*.)+(test).ts?(x)"],
    transform: {
        "^.+\\.(js|ts)$": "ts-jest",
    },
    transformIgnorePatterns: [
        "/node_modules/(?![@autofiy/autofiyable|@autofiy/property]).+\\.js$",
        "/node_modules/(?![@autofiy/autofiyable|@autofiy/property]).+\\.ts$",
        "/node_modules/(?![@autofiy/autofiyable|@autofiy/property]).+\\.tsx$",
    ],
}

put the packages that you want to ignore inside [] and separate them by |

in my case [@autofiy/autofiyable|@autofiy/property]