Error Resolving tailwind.config.ts During Upgrade to Tailwind CSS v4.0.0

[kabirjaipal]

When using the @tailwindcss/upgrade tool to upgrade to Tailwind CSS v4.0.0, the tool fails to resolve the tailwind.config.ts file due to an incorrect path resolution. Below are the steps to reproduce, expected behavior, and error logs.

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Steps to Reproduce

1. Run the upgrade command in a project with the following structure:

   Project Root
   ├── app
   │   └── globals.css
   ├── tailwind.config.ts
   

2. Execute:

   npx @tailwindcss/upgrade@next

3. Observe the error.

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Expected Behavior

The @tailwindcss/upgrade tool should resolve the tailwind.config.ts file and successfully link it to the CSS file (app/globals.css).

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Actual Behavior

The upgrade tool throws the following error:

Could not load the configuration file: Can't resolve '././E:\Codes\Web Development\kabirjaipal\tailwind.config.ts'
in 'C:\Users\kabir\AppData\Local\npm-cache\_npx\0044b4041b3b52e1\node_modules\@tailwindcss\upgrade\dist'

It seems like the tool is constructing the path incorrectly with an extra ././ prefix, leading to failure in resolving the configuration file.

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Environment Details

• Tailwind CSS Upgrade Version: @tailwindcss/upgrade@next
• Node.js Version: v20.11.1
• Operating System: Windows 11 Pro
• Project Directory Structure:
  • Configuration file: tailwind.config.ts
  • CSS file: app/globals.css

[philipp-spiess]

Heya! This is tracked as an issue in #15220. We're testing a fix for this right now so hopefully it'll be resolved shortly.