fix(transformer): don't ignore the entity after a stray '&'

[s7tya]

Fixes #13546

Currently, an input like & &, which should be transformed into & &, is incorrectly treated as a single entity. As a result, the output becomes & &.

This PR fixes the issue by resetting the start index when the decoder encounters another & before a ;.

[graphite-app]

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[Copilot]

Pull Request Overview

This PR fixes a bug in the JSX entity decoder where stray ampersands (&) would interfere with proper entity decoding. The issue occurred when an input like & & was incorrectly treated as a single entity instead of a stray & followed by a valid & entity.

• Updates the entity decoder to reset the start index when encountering another & before finding a ;
• Adds a test case to verify the fix for the stray ampersand scenario

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[overlookmotel]

Thank you for tackling this. Sorry that Copilot called your elegant solution into question!

Note: Boshen assigned Dunqing to this issue, but Dunqing and I had already discussed the other day. As I was the last to touch this code, I said I'd look at it first.

[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #13554 will not alter performance

_{Comparing s7tya:fix-entity-after-stray-amp (7f7be0d) with main (1425da2)¹}

Summary

✅ 37 untouched benchmarks

Footnotes

1. No successful run was found on main (e1adb0f) during the generation of this report, so 1425da2 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[graphite-app]

Merge activity

• Sep 6, 2:13 PM UTC: @s7tya we removed the merge queue label because we could not find a Graphite account associated with your GitHub profile.

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[robw-mercury]

Thank you all for addressing this so quickly!