perf(runtime-vapor): avoid allocating the hydration boundary closure on client render

[edison1105]

Summary by CodeRabbit

• Refactor
  • Improved the handling of hydration boundaries during component creation.
  • Streamlined deferred hydration processing and boundary cleanup for more consistent runtime behavior.
  • No changes to the public API or user-facing functionality.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Advanced

Run ID: c0f3c132-f4a0-46b8-90e6-649e4a521011

📥 Commits

Reviewing files that changed from the base of the PR and between 9a1aad4 and efd8481.

📒 Files selected for processing (1)

• packages/runtime-vapor/src/component.ts

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📝 Walkthrough

Walkthrough

The Vapor component runtime refactors hydration boundary handling. It claims the close anchor directly, trims boundaries through a module-level finalizer, and creates deferred finalization callbacks with the close node.

Changes

Vapor hydration boundary handling

Layer / File(s)	Summary
Hydration boundary finalization packages/runtime-vapor/src/component.ts	createComponent claims the hydration close anchor directly. Module-level helpers trim the boundary and create deferred finalization callbacks.

Estimated code review effort: 3 (Moderate) | ~15–30 minutes

Merge Risk: ⚪ Minimal · up to efd84

This change removes an unnecessary client-render closure while preserving hydration-boundary claiming and finalization behavior. No current merge-blocking risk is identified.

Suggested reviewers: zhiyuanzmj, danielroe

🚥 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%. Docstring coverage is scoped to functions touched by this diff. Analyzed 4 functions across 1 files.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Title check	✅ Passed	The title clearly and concisely describes the main change: avoiding hydration boundary closure allocation during client render in runtime-vapor.

• Fix all pre-merge checks with AI

✨ Finishing Touches 💡 1

📝 Generate docstrings 💡

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch edison/perf/hydration-boundary-closure

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commit: efd8481

[github-actions]

Size Report

Bundles

File	Size	Gzip	Brotli
compiler-dom.global.prod.js	87.2 kB	30.6 kB	26.9 kB
runtime-dom.global.prod.js	116 kB	43.8 kB	39.2 kB
vue.global.prod.js	176 kB	63.9 kB	56.9 kB

Usages

Name	Size	Gzip	Brotli
createApp (CAPI only)	53.2 kB	20.6 kB	18.8 kB
createApp	62.2 kB	24 kB	21.8 kB
createApp + vaporInteropPlugin	119 kB (+16 B)	42.9 kB (+11 B)	38.6 kB (+25 B)
createVaporApp	31.2 kB (+12 B)	12 kB (+5 B)	11 kB (+3 B)
createSSRApp	67.4 kB	26 kB	23.6 kB
createVaporSSRApp	37.4 kB (-19 B)	14.2 kB (-23 B)	13.1 kB (-15 B)
defineCustomElement	68.7 kB	25.9 kB	23.6 kB
defineVaporCustomElement	46.6 kB (+12 B)	16.9 kB (+8 B)	15.6 kB (+6 B)
overall	77.6 kB	29.5 kB	26.7 kB