fix(start-plugin-core): keep prerender trailing slash off the query string

[cjsewell]

fix(start-plugin-core): keep prerender trailing slash off the query string

Summary

The prerender crawler applied withTrailingSlash to the full request path including the query string. Without ufo's respectQueryAndFragment option, withTrailingSlash appends the slash to the end of the string, so it lands inside the last search-param value rather than on the path:

withTrailingSlash('/posts?page=2')       // "/posts?page=2/"   (before)
withTrailingSlash('/posts?page=2', true) // "/posts/?page=2"   (after)

With crawlLinks enabled, this corrupts any crawled link that carries a search param and turns it into an infinite loop. Each round appends one more slash to the value. Because every URL is unique the crawler's seen set never dedups, so the queue grows without bound and the build hangs.

Change

packages/start-plugin-core/src/prerender.ts:

-          const res = await requestWithRedirects(
-            withTrailingSlash(withBase(page.path, routerBasePath)),
+          const res = await requestWithRedirects(
+            withTrailingSlash(withBase(page.path, routerBasePath), true),

Test plan

• Prerender an app whose crawled HTML contains an <a href="/route?param=value">.
• Before: the crawler loops on /route?param=value%2F%2F… and never finishes.
• After: the request goes to /route/?param=value with the query preserved. The crawl then converges and dedups.

Closes #7837

Summary by CodeRabbit

• Bug Fixes

  • Fixed prerendering so trailing slashes remain part of the URL path instead of being appended to query parameters.
  • Prevented potential infinite crawl loops when link crawling is enabled.

• Release

  • Included in a patch release of the prerendering plugin.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 28da93e1-3e5e-42af-bf62-5ca13dd8225f

📥 Commits

Reviewing files that changed from the base of the PR and between 0b178a7 and 31ebb54.

📒 Files selected for processing (2)

• .changeset/prerender-trailing-slash-query.md
• packages/start-plugin-core/src/prerender.ts

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📝 Walkthrough

Walkthrough

The prerender crawler now applies trailing slashes to URL paths without modifying query strings. A patch changeset documents the fix for @tanstack/start-plugin-core.

Changes

Prerender query-safe URL normalization

Layer / File(s)	Summary
Preserve query boundaries during crawling packages/start-plugin-core/src/prerender.ts, .changeset/prerender-trailing-slash-query.md	The crawl request enables query-and-fragment-aware trailing-slash handling, and a patch changeset records the correction.

Estimated code review effort: 2 (Simple) | ~10 minutes

Suggested reviewers: schiller-manuel

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly summarizes the main change: fixing prerender trailing slashes on query-string URLs.
Linked Issues check	✅ Passed	The code change matches issue #7837 by passing respectQueryAndFragment so the slash stays on the path and query strings are preserved.
Out of Scope Changes check	✅ Passed	The PR only adds the targeted prerender fix and its changeset, with no unrelated code changes.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[LadyBluenotes]

We only review implementation PRs after the underlying issue has been reproduced, triaged, and the scope has been agreed with a maintainer. Please include a minimal reproduction in the PR and wait for maintainer confirmation before submitting a fix. I’m closing this PR for now; we can revisit it once the issue is confirmed