fix(minifier): handle { __proto__: null } instanceof Object correctly

[sapphi-red]

{ __proto__: null } instanceof Object should be false or kept as-is, or it was compressed to true.

[sapphi-red]

• fix(minifier): handle { __proto__: null } instanceof Object correctly #15217 👈 (View in Graphite)
• main

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[Copilot]

Pull Request Overview

This PR improves the constant evaluation of instanceof Object expressions in the minifier by handling more edge cases, particularly object literals with __proto__ set to null. The change fixes a test case and improves test coverage from 99.04% to 99.15%.

• Enhanced instanceof Object evaluation to correctly handle object expressions with __proto__ modifications
• Added test coverage for RegExp, arrow functions, function expressions, and class expressions
• Updated snapshot to reflect improved test pass rate

Reviewed Changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated 1 comment.

File	Description
tasks/coverage/snapshots/minifier_node_compat.snap	Updated test coverage statistics showing one additional passing test
crates/oxc_minifier/src/peephole/fold_constants.rs	Added test cases for various expression types with instanceof Object
crates/oxc_ecmascript/src/constant_evaluation/mod.rs	Enhanced instanceof evaluation logic to handle edge cases like __proto__: null

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[codspeed-hq]

CodSpeed Performance Report

Merging #15217 will not alter performance

_{Comparing 11-02-fix_minifier_handle___proto___null_instanceof_object_correctly (60b7c1f) with main (75c9164)}

Summary

✅ 37 untouched

[Boshen]

Merge activity

• Nov 2, 12:08 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Nov 2, 12:08 PM UTC: Boshen added this pull request to the Graphite merge queue.
• Nov 2, 12:29 PM UTC: Merged by the Graphite merge queue.