leimonio/use-nextjs-module-config

This is a repository for reproducing an issue with latest Next.js v13.5.

When using Next.js as an imported module import next from "next"; and running the dev server with providing a configuration object, the configuration object is not respected.

import next from "next";
// ...
// ...

next({
  dev: true,
  dir: nextRoot,
  conf: {
    env: {
      customKey: "my-value",
    },
  },
});

Folder structure

• next-root - a Next.js app using App Router
• next-root-pages - a Next.js app using Pages Router
• scirpts/next-run.mjs - the runner using next module

How to reproduce the issue

1. Clone the repo
2. Run npm run dev:custom - running the dev server for next-root
   Alternatively, run npm run dev:custom:pages - running the dev server for next-root-pages
3. Open browser at localhost:9988
4. Observe The value of customKey is: string is empty without containing any env key.
5. Uncomment the env configuration from next.config.js and rerun the command in step 2.
6. Observe The value of customKey is: my-value string is printing the env key my-value.