fix(mangler): reserve names from eval-containing scopes

[camc314]

fixes #17956

Refs: rolldown/rolldown#7843, rolldown/rolldown#7848

[camc314]

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This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
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• fix(mangler): reserve names from eval-containing scopes #18037 👈 (View in Graphite)
• fix(minifier): preserve return value of @__PURE__ IIFE in return statements #18036
• fix(minifier): skip inlining constant in scopes with eval #17926
• main

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[codspeed-hq]

Merging this PR will not alter performance

✅ 38 untouched benchmarks
⏩ 7 skipped benchmarks¹

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_{Comparing c/01-15-fix_mangler_reserve_names_from_eval-containing_scopes (29ad0e5) with c/01-15-fix_minifier_preserve_return_value_of___pure___iife_in_return_statements (17630cd)}

Footnotes

1. 7 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. ↩

[Copilot]

Pull request overview

This PR fixes a bug where the mangler could incorrectly shadow variables from scopes containing eval() calls. The fix ensures that variable names from eval-containing scopes are reserved and not reused as mangled names in other scopes.

Changes:

• Added collection of reserved names from eval-containing scopes during slot assignment
• Updated name generation to check against eval-reserved names to prevent shadowing
• Added comprehensive test cases covering various eval scenarios

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
crates/oxc_mangler/src/lib.rs	Implements eval-reserved name tracking by collecting variable names from eval scopes and excluding them from the mangled name pool
crates/oxc_minifier/tests/mangler/mod.rs	Adds helper test function and new test cases to verify correct behavior with eval in various scope configurations

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[Boshen]

Merge activity

• Jan 16, 5:20 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Jan 16, 5:20 AM UTC: Boshen added this pull request to the Graphite merge queue.