feat(ecmascript): treat [...arguments] as side effect free

[sapphi-red]

Treat [...arguments] as side effect free.

[sapphi-red]

• feat(ecmascript): treat [...arguments] as side effect free #13116 👈 (View in Graphite)
• main

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[Copilot]

Pull Request Overview

This PR treats [...arguments] as side effect free within function scopes to improve JavaScript minification capabilities. The change recognizes that spreading the arguments object in an array literal doesn't have side effects when arguments refers to the built-in function parameter object.

Key changes:

• Modified side effect analysis to treat arguments identifier as side effect free when it's a global reference
• Added arguments to the set of global variable names in the test context
• Added test coverage for the new behavior

Reviewed Changes

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

File	Description
crates/oxc_minifier/tests/ecmascript/may_have_side_effects.rs	Adds arguments to global variables and includes test for [...arguments] behavior
crates/oxc_ecmascript/src/side_effects/may_have_side_effects.rs	Implements logic to treat arguments identifier as side effect free in array spread context

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #13116 will not alter performance

_{Comparing 08-15-feat_ecmascript_treat_.arguments_as_side_effect_free (36386e4) with main (8459a12)¹}

Summary

✅ 34 untouched benchmarks

Footnotes

1. No successful run was found on main (36386e4) during the generation of this report, so 8459a12 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[Boshen]

Merge activity

• Aug 16, 2:41 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Aug 16, 2:41 AM UTC: Boshen added this pull request to the Graphite merge queue.
• Aug 16, 2:52 AM UTC: Merged by the Graphite merge queue.