fix(lint/css): treat math as a generic font family

[MHJahanbakhsh]

Summary

Fixes #11229.

math is a CSS Fonts Level 4 generic font family, but useGenericFontNames did not treat it as one, so declarations like font-family: math were incorrectly flagged as missing a generic fallback.

This adds math to FONT_FAMILY_KEYWORDS (kept sorted for binary_search) and covers it in the rule’s valid fixtures.

Test Plan

• cargo test -p biome_css_syntax -- test_font_family_keywords_sorted
• cargo test -p biome_css_analyze -- use_generic_font_names

Docs

No website docs PR needed; the rule now accepts the standard math keyword via the shared keyword list.

AI assistance

AI assistance was used to navigate the codebase and draft the change. The fix, tests, and PR text were reviewed and verified by me before submission.

[changeset-bot]

🦋 Changeset detected

Latest commit: 5116574

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 13 packages

Name	Type
@biomejs/biome	Patch
@biomejs/cli-win32-x64	Patch
@biomejs/cli-win32-arm64	Patch
@biomejs/cli-darwin-x64	Patch
@biomejs/cli-darwin-arm64	Patch
@biomejs/cli-linux-x64	Patch
@biomejs/cli-linux-arm64	Patch
@biomejs/cli-linux-x64-musl	Patch
@biomejs/cli-linux-arm64-musl	Patch
@biomejs/wasm-web	Patch
@biomejs/wasm-bundler	Patch
@biomejs/wasm-nodejs	Patch
@biomejs/backend-jsonrpc	Patch

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Reviewing files that changed from the base of the PR and between fc4d61e and 5116574.

⛔ Files ignored due to path filters (1)

• crates/biome_css_analyze/tests/specs/a11y/useGenericFontNames/valid.css.snap is excluded by !**/*.snap and included by **

📒 Files selected for processing (1)

• crates/biome_css_analyze/tests/specs/a11y/useGenericFontNames/valid.css

🚧 Files skipped from review as they are similar to previous changes (1)

• crates/biome_css_analyze/tests/specs/a11y/useGenericFontNames/valid.css

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---

Walkthrough

The CSS font-family keyword list now includes math. Accessibility tests cover math alone and after STIX Two Math. A patch changeset documents the update for useGenericFontNames.

Merge Risk: ⚪ Minimal · up to 51165

This localized change adds the standard CSS math generic font family and updates its valid fixtures; no actionable merge-blocking risk remains beyond normal checks and review.

🚥 Pre-merge checks | ✅ 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and concisely describes the main change: treating math as a generic CSS font family.
Description check	✅ Passed	The description explains the issue, implementation, valid fixtures, and test plan, and it matches the changeset.
Linked Issues check	✅ Passed	The changes satisfy issue #11229 by adding math to the font-family keywords and covering it with a valid rule fixture.
Out of Scope Changes check	✅ Passed	All reported changes support issue #11229 and the stated objective; no unrelated code changes are present.

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Actionable comments posted: 1

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Inline comments:
In `@crates/biome_css_analyze/tests/specs/a11y/useGenericFontNames/valid.css`:
- Line 13: Update the valid.css fixture declaration for the b selector to quote
the multi-word font family as "STIX Two Math" while preserving the lowercase
generic math keyword.

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📥 Commits

Reviewing files that changed from the base of the PR and between 6cd3263 and fc4d61e.

⛔ Files ignored due to path filters (1)

• crates/biome_css_analyze/tests/specs/a11y/useGenericFontNames/valid.css.snap is excluded by !**/*.snap and included by **

📒 Files selected for processing (3)

• .changeset/math-generic-font-family.md
• crates/biome_css_analyze/tests/specs/a11y/useGenericFontNames/valid.css
• crates/biome_css_syntax/src/keywords/mod.rs

Included review availability: Your plan includes up to 10 reviews per rolling hour; 9 remain after this review.

[codspeed-hq]

Merging this PR will not alter performance

✅ 29 untouched benchmarks
⏩ 278 skipped benchmarks¹

---

_{Comparing MHJahanbakhsh:fix/use-generic-font-names-math (5116574) with main (6cd3263)}

Footnotes

1. 278 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. ↩