fix(transformer/styled-components): remove repeat whitespace in CSS minification

[overlookmotel]

Follow-on after #13346. Remove multiple spaces preceding {, }, ,, or ;.

Previously we removed a single space, but wouldn't remove multiple whitespace characters in a row.

[overlookmotel]

• test(transformer/styled-components): fix test case #13377
• fix(transformer/styled-components): remove trailing whitespace in CSS minification #13376
• refactor(transformer/styled-components): clarify whitespace removal logic in CSS minification #13375
• fix(transformer/styled-components): remove space before line comment in CSS minification #13371
• fix(transformer/styled-components): fix block comment containing expression in CSS minification #13370
• fix(transformer/styled-components): remove repeat whitespace in CSS minification #13369 👈 (View in Graphite)
• main

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[Copilot]

Pull Request Overview

This PR fixes CSS minification in the styled-components transformer by removing multiple consecutive whitespace characters before CSS delimiters ({, }, ,, ;), not just single spaces as the previous implementation did.

• Enhanced whitespace compression logic to consume all consecutive whitespace characters
• Added test case to verify the fix handles multiple spaces and various whitespace patterns

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
crates/oxc_transformer/src/plugins/styled_components.rs	Updated minification logic to consume all consecutive whitespace instead of single characters
tasks/transform_conformance/tests/plugin-styled-components/test/fixtures/minify-whitespace-repeated/input.js	Test input with multiple spaces and whitespace patterns before CSS delimiters
tasks/transform_conformance/tests/plugin-styled-components/test/fixtures/minify-whitespace-repeated/output.js	Expected output showing properly minified CSS with whitespace removed
tasks/transform_conformance/tests/plugin-styled-components/test/fixtures/minify-whitespace-repeated/options.json	Babel configuration for the test case
tasks/transform_conformance/snapshots/oxc.snap.md	Updated test count reflecting the new passing test

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #13369 will degrade performances by 10.72%

_{Comparing 08-28-fix_transformer_styled-components_remove_repeat_whitespace_in_css_minification (35d83ca) with main (8f98841)¹}

Summary

❌ 1 regressions
✅ 37 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
❌	mangler[cal.com.tsx]	3.4 ms	3.8 ms	-10.72%

Footnotes

1. No successful run was found on main (35d83ca) during the generation of this report, so 8f98841 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[graphite-app]

Merge activity

• Aug 29, 3:14 AM UTC: Boshen added this pull request to the Graphite merge queue.
• Aug 29, 3:20 AM UTC: Merged by the Graphite merge queue.