fix(css): ignore font properties inside @supports rules in useGenericFontNames

[ddmoney420]

Summary

• Fixed false positive in useGenericFontNames rule when font or font-family properties are used inside @supports rules
• The @supports at-rule is used for feature detection (e.g., @supports (font: -apple-system-body) {}) and should not be treated as an actual font-family declaration

Fixes #8845

Test plan

• Added test cases for @supports (font: -apple-system-body) {} and @supports (font-family: -apple-system) {} to valid.css
• Tests pass locally with cargo test -p biome_css_analyze use_generic_font_names

AI Disclosure

This PR was written primarily by Claude Code.

🤖 Generated with Claude Code

[changeset-bot]

🦋 Changeset detected

Latest commit: f665652

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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[coderabbitai]

Walkthrough

Adds logic to the useGenericFontNames CSS a11y rule to skip linting when a declaration is inside a CSS @supports feature-detection at-rule. Introduces an internal helper that walks the AST to detect CssSupportsAtRule ancestry and early-returns to avoid analysing font / font-family tokens in @supports. Updates tests to include @supports and nested-at-rule scenarios. No public API changes.

Possibly related PRs

• fix(useGenericFontNames): handle CSS variable as last font-family value #8443: Touches the same use_generic_font_names rule and introduces helper checks / early-exit logic to avoid false positives.
• fix(linter): false positive for noDuplicateFontNames #7156: Modifies the same a11y lint implementation and its handling of font-related values.

Suggested reviewers

• siketyan
• ematipico

🚥 Pre-merge checks | ✅ 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately describes the main change: fixing the useGenericFontNames rule to ignore font properties inside @supports rules.
Description check	✅ Passed	The description clearly explains the fix, references issue #8845, includes test details, and discloses AI assistance appropriately.
Linked Issues check	✅ Passed	The PR addresses issue #8845 by implementing the desired outcome: suppressing useGenericFontNames errors for tokens inside @supports at-rules through a helper function.
Out of Scope Changes check	✅ Passed	All changes are scoped to fixing the useGenericFontNames rule for @supports blocks, with appropriate test additions and changelog entry.

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✨ Finishing touches

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🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment

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[coderabbitai]

Actionable comments posted: 1

🤖 Fix all issues with AI agents

In `@crates/biome_css_analyze/src/lint/a11y/use_generic_font_names.rs`:
- Around line 172-178: The current is_in_supports_at_rule uses
ancestors().find(...) which only checks the first matching at-rule ancestor and
misses cases where `@supports` is higher up (e.g. `@supports` wrapping `@media`);
change the ancestor scan to test all ancestors instead of using find: call
ancestors().any(...) and inside the closure check n.kind() ==
CssSyntaxKind::CSS_AT_RULE, cast to CssAtRule, call rule().ok() and return true
when matches!(rule, AnyCssAtRule::CssSupportsAtRule(_)); update the logic in
is_in_supports_at_rule accordingly so any ancestor `@supports` is detected
(referencing is_in_supports_at_rule, CssSyntaxKind::CSS_AT_RULE, CssAtRule,
rule().ok(), AnyCssAtRule::CssSupportsAtRule).

[codspeed-hq]

CodSpeed Performance Report

Merging this PR will not alter performance

_{Comparing ddmoney420:fix/use-generic-font-names-supports-false-positive (f665652) with main (2fb63a4)}

Summary

✅ 29 untouched benchmarks
⏩ 126 skipped benchmarks¹

Footnotes

1. 126 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. ↩

[ddmoney420]

Closing this PR — I opened too many contributions across projects and need to focus. Apologies for the noise.