pnpm workspace package with non shared lockfile break dev mode

[LukasGerm]

Link to the code that reproduces this issue

https://github.com/LukasGerm/pnpm-next-test

To Reproduce

1. pnpm i
2. Go into the packages/test-package and run pnpm build
3. Go to apps/my-app and run pnpm dev

Current vs. Expected behavior

Observe that

Expected would be that this works. Building the application works btw.

Provide environment information

Operating System:
  Platform: darwin
  Arch: arm64
  Version: Darwin Kernel Version 24.1.0: Thu Oct 10 21:06:57 PDT 2024; root:xnu-11215.41.3~3/RELEASE_ARM64_T6041
  Available memory (MB): 24576
  Available CPU cores: 12
Binaries:
  Node: 20.9.0
  npm: 10.1.0
  Yarn: N/A
  pnpm: 9.15.4
Relevant Packages:
  next: 15.1.6 // Latest available version is detected (15.1.6).
  eslint-config-next: 15.1.6
  react: 19.0.0
  react-dom: 19.0.0
  typescript: 5.7.3
Next.js Config:
  output: N/A

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

Turbopack

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

next dev (local)

Additional context

I also tested without turbopack, but the same issue

[LukasGerm]

For some reason I wrote that I had the same issue without turbopack. But seems if I remove the flag it's fixed

[DaltonPelkey]

Same exact issue here. Pnpm monorepo using turborepo with shared-workspace-lockfile=false. Running the dev server results in failed module resolutions from my monorepo packages, and only when appending the --turbopack flag.