Turbopack generated incorrect grid-template-areas value

Link to the code that reproduces this issue

To Reproduce

Note: I can't reproduce this issue in a new project (with the same dependency versions), which is why i didn't include a working link. But I experienced similar issues across multiple Next.js projects (v14 and v15).

Description: When running my dev environment with Turbopack, I noticed it's messing up the grid-template-areas values in the CSS output. This shouldn't happen since it's breaking my layouts, and Turbopack (or whatever it uses under the hood) shouldn't be modifying these values at all.

Note that I'm authoring CSS in Saas with CSS Module.

Current vs. Expected behavior

Current behavior (Turbopack enabled): incorrect

Expected behavior (Turbopack disabled): correct

My theory is that the class names are conflicting with the grid-area names (though this shouldn't be an issue). Changing the grid-area names fixed it. This only happened in dev mode (because I was using Turbopack), and not in production.

I've run into a few other Saas/Turbopack issues lately, but haven't had time to dig into them (I just turned off Turbopack and moved on). I'll update this issue or open a new one if it's something different.

Thank you.

Provide environment information

Operating System:
  Platform: darwin
  Arch: arm64
  Version: Darwin Kernel Version 23.6.0: Mon Jul 29 21:14:21 PDT 2024; root:xnu-10063.141.2~1/RELEASE_ARM64_T8103
  Available memory (MB): 16384
  Available CPU cores: 8
Binaries:
  Node: 22.9.0
  npm: 10.8.3
  Yarn: 1.22.19
  pnpm: 8.15.1
Relevant Packages:
  next: 14.2.14
  eslint-config-next: 14.2.14
  react: 18.3.1
  react-dom: 18.3.1
  typescript: 5.6.2
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

No response

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I did not open this issue, but it is relevant to me, what can I do to help?

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vercel / next.js