feat(napi/playground): call with_private_member_mappings() for private class member mangling

[Copilot]

Add with_private_member_mappings() support in napi playground like PR #14027 did

Summary

Successfully added support for private member mappings in the napi playground, enabling proper mangling of private class members (e.g., #field → #a).

Changes Made:

• Update MinifierReturn struct to include class_private_mappings field
• Update Minifier::build() method to capture and return class_private_mappings from Mangler
• Update apply_minification() to return Option<MinifierReturn> instead of tuple
• Update codegen() to accept Option<MinifierReturn> directly
• Refactor collect_private_members_from_semantic to be called inside build_with_semantic
• Fix clippy lint warning
• Test the changes to ensure mangling works correctly

Technical Details:

1. Extended MinifierReturn to include class_private_mappings field
2. Updated Minifier::build() to capture private member mappings
3. Refactored to return Option<MinifierReturn> directly instead of destructuring into tuple
4. Updated codegen() to accept the entire MinifierReturn struct
5. Made collect_private_members_from_semantic private and called it inside build_with_semantic
6. Updated build_with_semantic to return the collected mappings
7. Fixed clippy lint - replaced .map().unwrap_or() with .map_or()
8. Removed unnecessary imports (oxc_index, oxc_span, oxc_syntax) from playground

Testing:

✅ All existing tests pass
✅ Mangler tests pass (including private_member_mangling)
✅ Minifier tests pass
✅ Manual testing confirms private members are correctly mangled
✅ just minsize runs successfully
✅ Clippy warnings fixed

The implementation now matches the pattern used in crates/oxc/src/compiler.rs from PR #14027.

Original prompt

Add with_private_member_mappings() in @oxc-project/oxc/files/napi/playground/src/lib.rs like @oxc-project/oxc/pull/14027 did

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[graphite-app]

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[codspeed-hq]

CodSpeed Performance Report

Merging #14380 will degrade performances by 3.16%

_{Comparing copilot/fix-d9dce2c6-b15d-4a0f-861c-6e7ac12b07fe (bce31b5) with main (d1ff718)¹}

Summary

❌ 1 regression
✅ 36 untouched

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Mode	Benchmark	BASE	HEAD	Change
❌	Instrumentation	mangler[RadixUIAdoptionSection.jsx]	12.6 µs	13 µs	-3.16%

Footnotes

1. No successful run was found on main (bce31b5) during the generation of this report, so d1ff718 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[sapphi-red]

@copilot fix lint and run just minsize

[Copilot]

@copilot fix lint and run just minsize

Done in commit 6b458c7. Fixed clippy lint warning (replaced .map().unwrap_or() with .map_or()), and just minsize runs successfully showing improvements in minified output sizes.

[sapphi-red]

• feat(napi/playground): call with_private_member_mappings() for private class member mangling #14380 👈 (View in Graphite)
• main

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• hotfix - for urgent hot fixes, skip the queue and merge this PR next

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Please do not merge from GitHub as this will restart CI on PRs being processed by the merge queue.

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[Copilot]

Pull Request Overview

This PR adds support for private member mappings in the NAPI playground, enabling proper mangling of private class members (e.g., #field → #a) similar to the implementation in PR #14027.

Key changes:

• Extended MinifierReturn struct to include class_private_mappings field
• Updated Minifier::build() method to capture and return private member mappings from the Mangler
• Refactored method signatures to return Option<MinifierReturn> instead of tuples for cleaner API

Reviewed Changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
napi/playground/src/lib.rs	Updated minification pipeline to handle MinifierReturn struct and pass private member mappings to codegen
crates/oxc_minifier/src/lib.rs	Extended MinifierReturn struct and updated build method to capture class private mappings
crates/oxc_minifier/Cargo.toml	Added oxc_index dependency for IndexVec support
crates/oxc_mangler/src/lib.rs	Updated build_with_semantic to return private member mappings
tasks/track_memory_allocations/allocs_minifier.snap	Updated memory allocation snapshots reflecting code changes

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[Boshen]

Merge activity

• Oct 7, 7:47 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Oct 7, 7:47 AM UTC: Boshen added this pull request to the Graphite merge queue.
• Oct 7, 7:58 AM UTC: Merged by the Graphite merge queue.