Using jest-dom in vite setup with nx can't resolve typescript types.

[Shubham Choudhary]

• @testing-library/jest-dom version: 6.1.4
• node version: 20.3.1
• vitest version:~0.32.0
• npm version: 9.6.7

Relevant code or config:

vitest-setup.ts

import '@testing-library/jest-dom/vitest';

tsConfig include

"include": [
    "src/**/*.js",
    "src/**/*.jsx",
    "src/**/*.ts",
    "src/**/*.tsx",
  ]

Problem description:

I am using vite with nx setup. I am trying to use jest-dom. Tests is running fine. But I am not able to resolve typescript type.
I have followed the doc properly.

[Janeene Beeforth]

I've just run into the same issue of not having the vitest expect types include the jest-dom matchers, but in my case it was when using yarn with the pnpm nodeLinker.

What I found after investigation was that I needed to add @vitest/expect to my project's devDependencies for the types provided by @testing-library/jest-dom/vitest to work properly.

My investigations:

• I tried copying the type augmentation from @testing-library/jest-dom/vitest into one of my test files, and typescript complained that the module @vitest/expect didn't exist even though it had been installed by other libs.
• Yarn pnpm only symlinks the dependencies that you declare in your package.json file in the top-level/project's node_modules directory. Any dependencies for other modules are only linked inside their local node_modules and not available for you to import into your own project files.
• This meant that while other vitest libs pulled in @vitest/expect as a dependency, it wasn't available at the top level node_modules directory.
• The consequence was that the type augmentation in @testing-library/jest-dom/vitest.d.ts wasn't able to be applied to the @vitest/expect module - there wasn't a node_modules/@vitest/expect directory representing the module to be augmented.

By adding the devDependency for @vitest/expect to my package.json file, it was then linked in my project's node_modules directory allowing the types shipped with @testing-library/jest-dom/vitest to find the @vitest/expect package types to be updated.

[Akshay Vemul]

@dawnmist Thanks for this 🙌