Jest: Error in jest dep. during serverless npm build

[emadesantis]

🐛 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]

Looks like you get jest-diff v25 or 26. If it's 25, upgrade to latest, it's fixed. If it's 26, upgrade TS to 3.8.

[emadesantis]

Sorry, I'm sure I'm using v24, and still getting the error during a CRA npm build in a remote environment (a Docker container hosted in AWS, created in a CI/CD configuration).
The React framework version is: 16.13.1.
The same configuration 2 days ago worked correctly.
So, since in my local env I got no build problems, I guess it can be a CDN problem in a specific node (already happened in the past with another dependency).

[thymikee]

We've introduced import type syntax in v25, so at least one of your dependencies include jest-diff which is >=25. Try to track it down :) It's pretty straight forward if you have a lock file, which would also prevented differences between your local env and CI (at least with Yarn)

[emadesantis]

Ok, thank you, I already got the lock file. I solved upgrading TS at v3.8. I don't know why it is downloading jest >= 25. Anyway, project now has been build correctly, and it's working. Thank you again.

[jberube]

@thymikee [email protected] is imported from @types/[email protected] (see below).

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

Upgrading to [email protected] 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 [email protected] with default configurations after updating to [email protected].

As a workaround, downgrading [email protected] works pretty well.

@types/[email protected] probably shouldn't import [email protected] and import [email protected] instead.

EDIT: updating @types/[email protected] work and is clean. My types were out of date. My bad 😛

> npm ls jest-diff
...
├─┬ @types/[email protected]
│ └─┬ @types/[email protected]
│   └── [email protected]
└─┬ [email protected]
  └─┬ [email protected]
    └─┬ [email protected]
      └─┬ @jest/[email protected]
        └─┬ [email protected]
          ├── [email protected]
          └─┬ [email protected]
            └── [email protected]

[thymikee]

@jberube we don't control @types/jest, feel free to raise the issue there :)