fix(minifier): keep argument spread side effects against empty functions

[sapphi-red]

The spread arguments has sideeffects and has to be kept.

const foo = { [Symbol.iterator]() { throw new Error() } }
function bar() {}
bar(...foo) // throws

[sapphi-red]

• feat(ecmascript): check side effects inside static blocks #13404
• feat(minifier): remove pure function calls when the return value is not used #13403
• feat(ecmascript): support MayHaveSideEffects for Statements #13402
• fix(minifier): keep argument spread side effects against empty functions #13401 👈 (View in Graphite)
• main

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[Copilot]

Pull Request Overview

This PR fixes a bug in the minifier where spread arguments with side effects were incorrectly removed when calling empty functions. The fix ensures that spread arguments are preserved because they can throw errors during iteration, even when the target function is empty.

• Refactored argument handling to use a shared function that properly preserves spread arguments
• Updated test cases to verify that spread arguments are correctly preserved as array literals
• Made fold_arguments_into_needed_expressions function public for reuse

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
remove_unused_expression.rs	Made fold_arguments_into_needed_expressions function public and removed unnecessary blank line
remove_dead_code.rs	Replaced inline argument processing with shared function call and updated test expectations

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #13401 will not alter performance

_{Comparing 08-30-fix_minifier_keep_argument_spread_side_effects_against_empty_functions (3e902a0) with main (5d74332)¹}

Summary

✅ 38 untouched benchmarks

Footnotes

1. No successful run was found on main (3e902a0) during the generation of this report, so 5d74332 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[graphite-app]

Merge activity

• Aug 30, 4:14 AM UTC: Boshen added this pull request to the Graphite merge queue.
• Aug 30, 4:20 AM UTC: Merged by the Graphite merge queue.