[intellild]

Summary

• Add the custom_sourcemap feature and use it to gate the existing source-map code.
• Keep sourcemap as a compatibility alias. Both feature names use the existing Parcel implementation at this stage.

Example

A consumer that disables default features can select the new name with features = ["custom_sourcemap"]. Existing code that passes a Parcel map in PrinterOptions::source_map continues to work.

Validation

• cargo test --locked -p rspack-lightningcss --all-features (184 passed)
• cargo check --locked -p rspack-lightningcss --no-default-features --features custom_sourcemap
• cargo check --locked -p rspack-lightningcss --no-default-features --features sourcemap

Stack

1. Fix bundled source-map indices
2. Use std::fmt::Write for printer output
3. Serialize CSS through PrinterTrait
4. This PR
5. Custom source maps through generic PrinterOptions

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by OpenAI Codex

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[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-11-04T09:01:40.477263Z	44992a0	PR opened

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[codspeed]

Merging this PR will not alter performance

✅ 8 untouched benchmarks
⏩ 8 skipped benchmarks¹

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_{Comparing codex/rstack-rename-sourcemap-feature (43b17bc) with codex/rstack-to-css-printer-trait (62d0547)}

Footnotes

1. 8 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩