fix(linter/unicorn): fix ASI hazard in prefer-spread rule fixer

[camc314]

🤖 generated with help from Claude Opus 4.5

[camc314]

• fix(linter/unicorn): fix ASI hazard in prefer-spread rule fixer #16440 👈 (View in Graphite)
• feat(semantic): expose get_comment_at method #16439
• feat(ast): add get_comment_at to lookup a comment by span #16438
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #16440 will not alter performance

_{Comparing c/12-03-fix_linter_unicorn_fix_asi_hazard_in_prefer-spread_rule_fixer (b98310b) with main (5b10825)}

Summary

✅ 4 untouched
⏩ 41 skipped¹

Footnotes

1. 41 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. ↩

[camc314]

@overlookmotel assigned this to you to review as I'd appreciate another set of eyes. All good if you don't have time though - thanks

[overlookmotel]

My god this is tricky. It would be so much simpler and less error-prone if we had tokens to look at.

A couple more chars need adding to the check, I think, and a few notes on perf.

I've only nitpicked on perf because presumably this function is going to need to be used in lots of other rules too.

[Copilot]

Pull request overview

This PR fixes an ASI (Automatic Semicolon Insertion) hazard in the prefer-spread linter rule's auto-fixer. The fixer now detects when replacing code like Array.from(set) with [...set] could cause parsing issues due to JavaScript's ASI rules, and adds a semicolon prefix when needed (e.g., foo()\nArray.from(set) becomes foo()\n;[...set]).

Key Changes:

• Added could_be_asi_hazard() function to detect when a semicolon is needed before inserting code that starts with [
• Updated prefer-spread rule fixer to check for ASI hazards and add semicolons when necessary
• Added comprehensive test coverage for various ASI hazard scenarios including Unicode identifiers, comments, and irregular whitespace

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.

File	Description
crates/oxc_linter/src/ast_util.rs	Implements ASI hazard detection with could_be_asi_hazard() and helper function find_last_meaningful_char() to scan backwards through source text, skipping whitespace and comments
crates/oxc_linter/src/rules/unicorn/prefer_spread.rs	Threads node parameter through to fixer functions and adds ASI hazard checks to all auto-fixes for Array.from(), array.slice(), array.toSpliced(), and string.split()

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[camc314]

Merge activity

• Dec 9, 11:11 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Dec 9, 11:11 AM UTC: camc314 added this pull request to the Graphite merge queue.
• Dec 9, 11:17 AM UTC: Merged by the Graphite merge queue.