perf(parser): add separate token kinds for BigInt literals

[Boshen]

Summary

Add separate token kinds (DecimalBigInt, BinaryBigInt, OctalBigInt, HexBigInt) to eliminate the ends_with('n') string check when parsing BigInt literals.

[graphite-app]

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[Copilot]

Pull Request Overview

This PR adds separate token kinds for BigInt literals to eliminate string suffix checking during parsing. The lexer now directly communicates BigInt vs Number types through the token kind, improving performance by replacing string operations with enum comparisons.

Key changes:

• Added four new Kind enum variants for BigInt literals (DecimalBigInt, BinaryBigInt, OctalBigInt, HexBigInt)
• Updated lexer logic to return BigInt-specific kinds when 'n' suffix is detected
• Modified parser to match on BigInt kinds instead of performing string suffix checks

Reviewed Changes

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

File	Description
crates/oxc_parser/src/lexer/kind.rs	Added new BigInt token kinds and updated is_number() method
crates/oxc_parser/src/lexer/numeric.rs	Modified lexer to return BigInt kinds when 'n' suffix is consumed
crates/oxc_parser/src/js/expression.rs	Updated parser to match BigInt kinds directly instead of string checking

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[codspeed-hq]

CodSpeed Performance Report

Merging #14405 will not alter performance

_{Comparing perf/add-bigint-token-kinds (791c72a) with main (266b982)¹}

Summary

✅ 37 untouched

Footnotes

1. No successful run was found on main (791c72a) during the generation of this report, so 266b982 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[Boshen]

Merge activity

• Oct 7, 9:55 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Oct 7, 9:55 AM UTC: Boshen added this pull request to the Graphite merge queue.
• Oct 7, 10:01 AM UTC: Merged by the Graphite merge queue.