NextJS with Jest and Nuqs

[f1yingbanana]

Context

What's your version of nuqs?

    "nuqs": "^2.4.1",

What framework are you using?

• ✅ Next.js (app router)

Which version of your framework are you using?

    "next": "15.0.3",

Description

I am unable to test with nuqs without mocking in NextJS and Jest. NextJS has its own code transformer and Jest config wrapper, so it is difficult to follow the Nuqs/Jest guide and use experimental ESM support. Instead, I've been relying on NextJS config transpilePackages option to port the node packages back to CommonJS.

However, with the esm-only.cjs file, I'll get an exception in my tests. But even if I remove the manual exception, my test still cannot find the correct module. I suspect maybe #880 might fix this, but with the NextJS Jest wrapper over Jest config, it didn't work :(

Really want to not mock and wish jest supports ESM out of the box :( but meanwhile, are there any workarounds?

Reproduction

1. Setup Jest in NextJS following NextJS testing guide
2. Try to use Nuqs in a Jest test
3. Fails :(

[franky47]

Thanks for the report, I'll try and reproduce it, in the mean time, could you tell me what version of Node.js you're using please?

My recommendations would be:

1. Use Vitest (very similar API to Jest, runs ESM natively and is way faster)
2. If not possible, try the latest versions of Node.js which include the require(esm) feature for interoperability.

[f1yingbanana]

Yeah I was new to web-dev and it seems like I picked the wrong testing framework 🥲 I'll see if I can switch.

Meanwhile I'm on Node 22.