fix(externals): trace CJS require() dependencies in production builds

[dake3601]

🔗 Linked issue

#4093

❓ Type of change

• 📖 Documentation (updates to the documentation, readme, or JSdoc annotations)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality like performance)
• ✨ New feature (a non-breaking change that adds functionality)
• 🧹 Chore (updates to the build process or auxiliary tools and libraries)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

The resolveId handler had if (rOpts.custom?.["node-resolve"]) return null; which blanket-skipped CJS require resolutions, preventing packages like bufferutil (in NodeNativePackages) from being externalized and traced even when matched by the include filter.

Fix: check opts.trace before skipping. In dev mode (no tracing), skip as before. In production, resolve directly via tryResolve to avoid recursion and externalize if the resolved path matches the include filter.

Includes test fixtures (nitro-cjs-untrace → @fixture/nitro-native-mock) and a node preset test that verifies CJS require deps are traced to the output node_modules.

📝 Checklist

• I have linked an issue or discussion.
• I have updated the documentation accordingly.

[vercel]

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[coderabbitai]

📝 Walkthrough

Walkthrough

Modified externals resolution logic to handle nested node-resolve scenarios with conditional tracing-based resolution and CommonJS unwrapping. Re-enabled nitro and static presets in presets export. Added CommonJS untrace utility exposure in test fixtures and a new test case verifying CJS require() dependency tracing.

Changes

Cohort / File(s)	Summary
Externals Resolution Logic src/build/plugins/externals.ts	Enhanced resolve path handling for nested node-resolve scenarios: added trace-mode-dependent resolution behavior, implemented CommonJS unwrapping when filter conditions are met, and differentiated resolution paths based on resolver type.
Presets Configuration src/presets/_all.gen.ts	Re-enabled nitro and static presets by re-adding imports and spreads; relocated preset spreads from earlier position to end of export array.
Test Fixtures and Coverage test/fixture/server/routes/modules.ts, test/presets/node.test.ts	Exposed cjsUntrace utility from nitro-cjs-untrace module in test fixtures; added test case verifying CommonJS require() dependencies are properly externalized and traced.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

Possibly related issues

• Nitro build does not add native externals that are required. #4093: The externals resolution changes (nested node-resolve handling, trace-mode resolution, and CommonJS unwrapping) directly address CJS externalization pathway for missing native externals.

Possibly related PRs

• feat: automatically trace known native pkgs #3923: Modifies externals.ts with related changes to resolve paths and CJS unwrapping logic.
• refactor!: overhaul externals support #3799: Modifies externals.ts resolution logic for node-resolve and CommonJS handling with trace behavior adjustments.

🚥 Pre-merge checks | ✅ 2 | ❌ 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 (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The pull request title follows conventional commits format with 'fix' type and descriptive subject clearly related to the changeset.
Description check	✅ Passed	The PR description clearly explains the bug being fixed: the resolveId handler was unconditionally skipping CJS require resolutions, preventing packages from being externalized. It describes the solution (checking opts.trace and using tryResolve), mentions the linked issue #4093, and references the test fixtures and node preset test added.

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✨ Finishing Touches

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[pi0]

Please provide a reproduction first 🙏🏼

[dake3601]

Done! https://github.com/dake3601/nitro-cjs-trace-repro
also added the repro to the github issue.

[giggo1604]

@dake3601 would that solve #4068?

[dake3601]

@giggo1604 I don't think so, this just helps trace cjs deps.

[dake3601]

@pi0 could I please get a review?