fix(formatter): Count emoji sequences correctly

[leaysgur]

Fixes #17271

It seems U+FE0F is not counted as 1 by char. Please see https://github.com/oxc-project/oxc/pull/17331/changes#diff-68ae34cbf2a12b1e38d6edaa09bda33717157a1c90311e2adcd8f060eed45223R572-R579 for explanation.

[leaysgur]

• feat(formatter): Support Vitest test functions #17340
• fix(formatter): Fix Deno() to not detect as test functions #17339
• fix(formatter): Handle more test functions #17337
• fix(formatter): Count emoji sequences correctly #17331 👈 (View in Graphite)
• main

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[Copilot]

Pull request overview

This PR fixes a bug where emoji sequences (particularly those with variation selectors) were counted incorrectly when calculating text width in the formatter. The fix changes from character-by-character width calculation to segment-based calculation using UnicodeWidthStr::width(), which correctly handles complex Unicode sequences as grapheme clusters.

Key Changes:

• Replaced character-by-character iteration with segment-based width calculation in TextWidth::from_text()
• Removed unused UnicodeWidthChar import and retained UnicodeWidthStr
• Added comprehensive test coverage for emoji sequences with variation selectors

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[codspeed-hq]

CodSpeed Performance Report

Merging #17331 will not alter performance

_{Comparing 12-24-fix_formatter_count_emoji_sequences_correctly (b58d3de) with main (b00da37)¹}

Summary

✅ 38 untouched
⏩ 7 skipped²

Footnotes

1. No successful run was found on main (0e79375) during the generation of this report, so b00da37 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

2. 7 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. ↩

[Dunqing]

Please add a test in the fixtures; I want to see the final output

[Dunqing]

Nice finding

[graphite-app]

Merge activity

• Dec 25, 1:12 AM UTC: Dunqing added this pull request to the Graphite merge queue.
• Dec 25, 1:23 AM UTC: Merged by the Graphite merge queue.