Inconsistent context.resolvedUrl behavior in getServerSideProps after middleware rewrite

[guinnod]

Link to the code that reproduces this issue

https://github.com/guinnod/next-js-issue

To Reproduce

1. Start the application (npm run build & npm run start)
2. Go to the page /old?param=oldValue

Current vs. Expected behavior

When accessing /old?param=oldValue
Expected resolvedUrl: /new?param=newValue
Actual resolvedUrl: /new?param=oldValue

Expected Behavior

After middleware rewrites both the pathname and query parameters, context.resolvedUrl in getServerSideProps should reflect the complete rewritten URL, including both the new pathname and the new query parameters.

Actual Behavior

While the middleware successfully rewrites the URL and the application correctly routes to the new path, context.resolvedUrl in getServerSideProps shows a mixed state:

• Pathname in resolvedUrl is correctly updated to the rewritten value
• Query parameters in resolvedUrl remain as the original values before rewrite

Provide environment information

Operating System:
  Platform: darwin
  Arch: arm64
  Version: Darwin Kernel Version 23.5.0: Wed May  1 20:12:58 PDT 2024; root:xnu-10063.121.3~5/RELEASE_ARM64_T6000
  Available memory (MB): 16384
  Available CPU cores: 10
Binaries:
  Node: 20.14.0
  npm: 10.7.0
  Yarn: 1.22.22
  pnpm: N/A
Relevant Packages:
  next: 15.2.0-canary.3 // Latest available version is detected (15.2.0-canary.3).
  eslint-config-next: N/A
  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)

Middleware, Pages Router

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

next dev (local), next start (local), Vercel (Deployed)

Additional context

The bug exhibits inconsistent behavior across different projects and environments:

1. Original Production Project (Next.js 14.1.2):

• Deployed on Vercel: Bug present with incorrect pathname in resolvedUrl but correct query parameters
• Local development: Bug not reproducible even with identical Vercel environment variables
• Local production build (next build && next start): Bug not reproducible
• With locales in pathname (e.g., / and /en): Bug does not manifest
• Vercel deployment logs confirm the bug's existence in production

2. Reproduction Project (created with npx create-next-app -e reproduction-template):

• Shows opposite behavior: pathname is correct but query parameters are wrong
• Demonstrates that the bug's behavior is not consistent even when attempting to reproduce it

This inconsistency in behavior makes the bug particularly concerning:

• The same codebase behaves differently between Vercel deployment and local environment
• Different projects exhibit opposite symptoms (either pathname or query parameters being incorrect)
• The presence of locale routing appears to affect the bug's manifestation
• The bug's behavior is not sustainable across different setups and configurations

This variation in behavior suggests a deeper underlying issue with how URL rewrites are handled in different contexts and configurations within Next.js.