fix: respect app.baseURL in devtools iframe src

[fabkho]

Summary

• Fix DevTools custom tab iframe not loading when app.baseURL is set to a non-root value (e.g., behind a reverse proxy)
• Use joinURL from ufo to prepend app.baseURL to the devtools iframe src

Fixes #321

Context

This is the same bug that was reported and fixed in @nuxt/a11y:

• Issue: Infinite RPC reconnection loop when running behind reverse proxy (nginx) a11y#243
• Fix: fix: prevent infinite RPC reconnection loop and respect app.baseURL in devtools a11y#278

Changes

• src/devtools.ts: Import joinURL from ufo and wrap DEVTOOLS_UI_ROUTE with joinURL(nuxt.options.app?.baseURL || '/', DEVTOOLS_UI_ROUTE) in the addCustomTab call
• package.json: Add ufo as an explicit dependency

[coderabbitai]

📝 Walkthrough

Walkthrough

This pull request adds a runtime dependency on the ufo package (version ^1.6.3) to package.json and updates the DevTools iframe src in src/devtools.ts to properly respect the app's baseURL configuration. The iframe src is now constructed by joining nuxt.options.app?.baseURL (or '/' as a fallback) with the DEVTOOLS_UI_ROUTE constant using the joinURL function from the newly added ufo package, fixing an issue where the iframe would fail to load when the app is served behind a reverse proxy with a custom base path.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately and concisely describes the main change: respecting app.baseURL in the devtools iframe src attribute.
Description check	✅ Passed	The description clearly explains the bug fix, its context, and provides all necessary changes with specific file modifications and linked issue references.
Linked Issues check	✅ Passed	The pull request fully addresses issue #321 by implementing the exact fix described: importing joinURL from ufo and wrapping DEVTOOLS_UI_ROUTE with it in src/devtools.ts, plus adding ufo as a dependency.
Out of Scope Changes check	✅ Passed	All changes are directly scoped to the requirements: only src/devtools.ts and package.json are modified to fix the baseURL issue with no extraneous modifications.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@package.json`:
- Line 51: package.json was updated to add the "ufo" dependency but the pnpm
lockfile wasn't regenerated, which breaks CI with frozen-lockfile; run pnpm
install (or pnpm install --lockfile-only) locally to regenerate pnpm-lock.yaml,
verify the lockfile includes the new "ufo" entry, and commit the updated
pnpm-lock.yaml alongside the package.json change so CI/release can proceed.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 31d2084b-0637-4e99-8852-622fbe03eed8

📥 Commits

Reviewing files that changed from the base of the PR and between 86b47d2 and 7f48fc0.

📒 Files selected for processing (2)

• package.json
• src/devtools.ts

[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/@nuxt/hints@322

commit: 81489e1