fix(mangler): mangle private class members in subsequent classes correctly

[sapphi-red]

fixes #14342

[sapphi-red]

• fix(mangler): avoid reusing same mangled names in the outer class #14362
• fix(mangler): mangle private class members in subsequent classes correctly #14361 👈 (View in Graphite)
• main

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[Copilot]

Pull Request Overview

This PR fixes private class member mangling in subsequent classes by changing from a linear Vec-based approach to using IndexVec with ClassId for proper class tracking during code generation.

• Replaces Vec with IndexVec<ClassId, FxHashMap> for class private member mappings
• Updates the class tracking mechanism in codegen to use a proper stack with ClassId identifiers
• Fixes the private identifier lookup to correctly find mangled names across nested class scopes

Reviewed Changes

Copilot reviewed 6 out of 7 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
crates/oxc_mangler/src/lib.rs	Changes return type from Vec to IndexVec for class private mappings
crates/oxc_mangler/Cargo.toml	Adds oxc_index dependency for IndexVec support
crates/oxc_codegen/src/lib.rs	Updates class tracking with proper ClassId-based stack implementation
crates/oxc_codegen/src/gen.rs	Fixes private identifier lookup to correctly iterate through class hierarchy
crates/oxc_minifier/tests/mangler/mod.rs	Adds test case for different private member names across classes
crates/oxc_minifier/tests/mangler/snapshots/private_member_mangling.snap	Test snapshot showing correct mangling output

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[codspeed-hq]

CodSpeed Performance Report

Merging #14361 will not alter performance

_{Comparing 10-06-fix_mangler_mangle_private_class_members_in_subsequent_classes_correctly (fc519c8) with main (e605222)¹}

Summary

✅ 37 untouched

Footnotes

1. No successful run was found on main (ab42b48) during the generation of this report, so e605222 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[graphite-app]

Merge activity

• Oct 6, 9:26 AM UTC: Boshen added this pull request to the Graphite merge queue.
• Oct 6, 9:35 AM UTC: Merged by the Graphite merge queue.