Error in jest dep. during serverless npm build

🐛 Bug Report

Hello, I’m trying to build a project which have jest as dependency. It’s a Create React App based project. I’m building the process through a serverless CI/CD for AWS Lambda environment (it launches a simple npm i / npm run build). Two days ago I successfully deployed the project with no errors. Today I’m getting an error during the build process at the following line in the jest-diff module:

import type { DiffOptions } from './types';

In the package.json file I’ve got the following dependencies configuration:

• TypeScript version 3.5.2
• Jest: 24.0.15

the same configuration of the last succesful build of two days ago. I encounter the problem only in the AWS infrastructure, not locally. Thanks in advance.

[thymikee]

@jberube we don’t control @types/jest, feel free to raise the issue there 😃

[jberube]

@thymikee jest-diff@26.0.1 is imported from @types/jest@24.0.15 (see below).

That caused my project to break with the error mentioned in OP.

Upgrading to typescript@3.8 comes with a host of issues in some projects, since not all libraries supports it well at the moment. In my case, jest wasn’t importing non-ES5 or non-js modules correctly using react-scripts@3.4.1 with default configurations after updating to typescript@3.8.

As a workaround, downgrading jest-diff@24.9.0 works pretty well.

@types/jest-diff@24.x probably shouldn’t import jest-diff@26.0.1 and import jest-diff@24.9.0 instead.

EDIT: updating @types/jest@24.9.1 work and is clean. My types were out of date. My bad 😛

> npm ls jest-diff
...
├─┬ @types/jest@24.0.15
│ └─┬ @types/jest-diff@24.3.0
│   └── jest-diff@26.0.1
└─┬ react-scripts@3.0.1
  └─┬ jest@24.7.1
    └─┬ jest-cli@24.9.0
      └─┬ @jest/core@24.9.0
        └─┬ jest-snapshot@24.9.0
          ├── jest-diff@24.9.0
          └─┬ jest-matcher-utils@24.9.0
            └── jest-diff@24.9.0