Not working with Yarn pnpm strategy

[coreyward]

Link to the code that reproduces this issue

https://github.com/coreyward/next-yarn-pnpm-issue

To Reproduce

Run yarn dev in the linked repo root, then open the app at localhost:3000. This will trigger the following error:

Error: Invariant: Expected relative import to start with "next/", found "package/dist/server/future/route-modules/pages/module.compiled"
at [Symbol.replace] ()
at String.replaceAll ()

Current vs. Expected behavior

Next works fine when using the legacy node_modules approach for installing dependencies, and seems to have support for the Plug-N-Play strategy of pnpm, but it does not seem to account for Yarn’s hybrid pnpm strategy which is described as follows:

node-modules will be created using symlinks and hardlinks to a global content-addressable store.

The issue seems to come about in the load-entrypoint, which seems to make unsafe assumptions about where dependencies are located on disk relative to the project. The specific error is coming from Next.js here:

next.js/packages/next/src/build/load-entrypoint.ts

Lines 63 to 70 in 9d16112

	// Verify that the relative import is relative to the `next` package. This
	// will catch cases where the constants at the top of the file were not
	// updated after the file was moved.
	if (!relative.startsWith('next/')) {
	throw new Error(
	`Invariant: Expected relative import to start with "next/", found "${relative}"`
	)
	}

Provide environment information

Operating System:
  Platform: darwin
  Arch: arm64
  Version: Darwin Kernel Version 23.4.0
Binaries:
  Node: 20.11.0
  npm: 10.2.4
  Yarn: 4.2.2
  pnpm: N/A
Relevant Packages:
  next: 14.3.0-canary.62 // Latest available version is detected (14.3.0-canary.62).
  eslint-config-next: N/A
  react: 19.0.0-beta-4508873393-20240430
  react-dom: 19.0.0-beta-4508873393-20240430
  typescript: 5.1.3
Next.js Config:
  output: N/A

Which area(s) are affected? (Select all that apply)

Module Resolution, Runtime

Which stage(s) are affected? (Select all that apply)

next dev (local), next build (local)

Additional context

This may be related to #16471.

[Yukigamine]

I have been seeing this issue with Yarn 4.x–also using pnpm.

Downgrading to Yarn 3.x is how I fixed the issue in my projects.

[coreyward]

@Yukigamine If you're able to use one of the other strategies it works (node-modules or pnp), but they both have other drawbacks (especially pnp).

[Yukigamine]

So the issue seems to be related specifically to the pnpm strategy using Yarn 4.x in Next.JS projects.