feat: stabilize lazy compilation middleware

[chenjiahan]

Summary

Since the lazyCompilation option was stabilized in Rspack 1.5, we can also stabilize lazyCompilationMiddleware to keep things consistent.

Related links

• feat: move experiments.lazyCompilation to configuration toplevel #11337

Checklist

• Tests updated (or not required).
• Documentation updated (or not required).

[netlify]

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🔨 Latest commit	8a6674a
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[Copilot]

Pull request overview

This PR stabilizes the lazyCompilationMiddleware by promoting it from the experimental experiments namespace to the main Rspack API. This change aligns with the earlier stabilization of the lazyCompilation configuration option in Rspack 1.5.

Key Changes

• Moved lazyCompilationMiddleware from rspack.experiments.lazyCompilationMiddleware to rspack.lazyCompilationMiddleware
• Added deprecation marker to the old experiments location for backward compatibility
• Updated all documentation and code examples to use the new stable API
• Added JSDoc documentation for the newly stabilized middleware function

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
website/docs/en/guide/features/lazy-compilation.mdx	Updated English documentation to reference the new stable API location and added migration notice
website/docs/zh/guide/features/lazy-compilation.mdx	Updated Chinese documentation to reference the new stable API location and added migration notice
tests/e2e/fixtures/rspack.ts	Updated test fixture to use the new stable API import
packages/rspack/src/exports.ts	Added top-level export for lazyCompilationMiddleware and marked the experiments version as deprecated
packages/rspack/src/builtin-plugin/lazy-compilation/middleware.ts	Added JSDoc comment documenting the middleware function
packages/rspack/etc/core.api.md	Updated TypeScript API definitions to reflect the stabilization and deprecation
packages/rspack-test-tools/src/plugin/lazy-compilation-test-plugin.ts	Updated test plugin to use the new stable API import
packages/rspack-cli/src/commands/serve.ts	Updated CLI serve command to use the new stable API

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[github-actions]

Rsdoctor Bundle Diff Analysis

Found 5 project(s) in monorepo.

📁 react-10k

Path: ../build-tools-performance/cases/react-10k/dist/rsdoctor-data.json

📌 Baseline Commit: 6f3f4de245 | PR: #12431

Metric	Current	Baseline	Change
📊 Total Size	5.7 MB	5.7 MB	0 B (0.0%)
📄 JavaScript	5.7 MB	5.7 MB	0 B (0.0%)
🎨 CSS	21.0 B	21.0 B	0 B (0.0%)
🌐 HTML	0 B	0 B	N/A
📁 Other Assets	0 B	0 B	N/A

📦 Download Diff Report: react-10k Bundle Diff

📁 react-1k

Path: ../build-tools-performance/cases/react-1k/dist/rsdoctor-data.json

📌 Baseline Commit: 6f3f4de245 | PR: #12431

Metric	Current	Baseline	Change
📊 Total Size	823.6 KB	823.6 KB	0 B (0.0%)
📄 JavaScript	823.6 KB	823.6 KB	0 B (0.0%)
🎨 CSS	0 B	0 B	N/A
🌐 HTML	0 B	0 B	N/A
📁 Other Assets	0 B	0 B	N/A

📦 Download Diff Report: react-1k Bundle Diff

📁 react-5k

Path: ../build-tools-performance/cases/react-5k/dist/rsdoctor-data.json

📌 Baseline Commit: 6f3f4de245 | PR: #12431

Metric	Current	Baseline	Change
📊 Total Size	2.7 MB	2.7 MB	0 B (0.0%)
📄 JavaScript	2.7 MB	2.7 MB	0 B (0.0%)
🎨 CSS	21.0 B	21.0 B	0 B (0.0%)
🌐 HTML	0 B	0 B	N/A
📁 Other Assets	0 B	0 B	N/A

📦 Download Diff Report: react-5k Bundle Diff

📁 rome

Path: ../build-tools-performance/cases/rome/dist/rsdoctor-data.json

📌 Baseline Commit: 6f3f4de245 | PR: #12431

Metric	Current	Baseline	Change
📊 Total Size	984.3 KB	984.3 KB	0 B (0.0%)
📄 JavaScript	984.3 KB	984.3 KB	0 B (0.0%)
🎨 CSS	0 B	0 B	N/A
🌐 HTML	0 B	0 B	N/A
📁 Other Assets	0 B	0 B	N/A

📦 Download Diff Report: rome Bundle Diff

📁 ui-components

Path: ../build-tools-performance/cases/ui-components/dist/rsdoctor-data.json

📌 Baseline Commit: 6f3f4de245 | PR: #12431

Metric	Current	Baseline	Change
📊 Total Size	2.1 MB	2.1 MB	0 B (0.0%)
📄 JavaScript	2.0 MB	2.0 MB	0 B (0.0%)
🎨 CSS	83.0 KB	83.0 KB	0 B (0.0%)
🌐 HTML	0 B	0 B	N/A
📁 Other Assets	0 B	0 B	N/A

📦 Download Diff Report: ui-components Bundle Diff

Generated by Rsdoctor GitHub Action

[github-actions]

📦 Binary Size-limit

Comparing 8a6674a to chore: bump swc_experimental to fix parsing utf8 in template (#12431) by CPunisher

🙈 Size remains the same at 48.20MB

[codspeed-hq]

CodSpeed Performance Report

Merging #12429 will not alter performance

_{Comparing stablize_lazy_middleware_1212 (8a6674a) with main (6f3f4de)}

Summary

✅ 17 untouched