fix(css): ignore @supports queries in useGenericFontNames rule

[LouisLau-art]

Summary

Fixes #8845 by making lint/a11y/useGenericFontNames ignore font / font-family declarations that appear in the @supports (...) condition (supports feature declarations), so feature-detection tokens like -apple-system-body don’t trigger a misleading a11y diagnostic.

This does not ignore style declarations inside the @supports { ... } block — those are still linted as usual.

Changeset: .changeset/quiet-ads-fix2.md

AI assistance: Yes (OpenAI Codex was used for editing and response drafting.)

Test Plan

• cargo test -p biome_css_analyze --test spec_tests a11y::use_generic_font_names::valid_css
• cargo test -p biome_css_analyze --test spec_tests a11y::use_generic_font_names::invalid_css

Docs

N/A

[changeset-bot]

🦋 Changeset detected

Latest commit: 186f5ae

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

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[coderabbitai]

Walkthrough

Adds a guard to the useGenericFontNames lint to skip diagnostics when a CssGenericProperty appears inside the condition of a CSS @supports feature declaration. Implements an is_in_supports_feature_declaration helper that walks ancestor nodes to detect CSS_SUPPORTS_FEATURE_DECLARATION, and the lint's run returns early when that helper is true. Tests were updated (fixing a selector and adding an @supports case) and a changeset recording the patch was added. No public API changes.

Possibly related PRs

• fix(linter): false positive for noDuplicateFontNames #7156: Refactors font-value handling in the same use_generic_font_names lint implementation — strong code-level overlap.

Suggested reviewers

• siketyan
• ematipico

🚥 Pre-merge checks | ✅ 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and concisely describes the main change: ignoring @supports queries in the useGenericFontNames CSS linting rule.
Description check	✅ Passed	The description thoroughly explains the fix, distinguishing between ignoring feature declarations in @supports conditions versus style declarations inside the block, and includes test plan and changeset reference.
Linked Issues check	✅ Passed	The changes fully address issue #8845 by preventing useGenericFontNames from triggering on font tokens used in @supports feature conditions, whilst preserving linting for declarations inside the block.
Out of Scope Changes check	✅ Passed	All changes are directly scoped to the objective: helper function for @supports detection, test updates with valid and invalid cases, and changeset documentation. No extraneous modifications present.

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✨ Finishing touches

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• 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 166-173: The helper is_in_supports_at_rule currently only checks
the first ancestor that is an at‑rule (using find) so nested cases like
`@supports` { `@media` { ... } } are missed; update it to examine all ancestor
at‑rules by iterating/filtering all ancestors with kind() ==
CssSyntaxKind::CSS_AT_RULE, casting each to CssAtRule, retrieving rule().ok(),
and returning true if any of those rules matches
AnyCssAtRule::CssSupportsAtRule(_); reference the function
is_in_supports_at_rule and the types CssGenericProperty, CssAtRule, and
AnyCssAtRule when making the change.

[dyc3]

Please use our PR template.

[coderabbitai]

Actionable comments posted: 1

🤖 Fix all issues with AI agents

In @.changeset/quiet-ads-fix2.md:
- Line 5: Update the changeset title wording for clarity: in
.changeset/quiet-ads-fix2.md replace the phrase "ignore `@supports` queries in
useGenericFontNames rule" with a smoother variant such as "ignore `@supports`
queries within useGenericFontNames rule" or "ignore `@supports` queries inside
useGenericFontNames rule" so the message reads grammatically fluent while
preserving the same intent and scope.

[LouisLau-art]

Updated the PR body to follow the template (including AI assistance disclosure) and refined the changeset wording as suggested.

[LouisLau-art]

Thanks for the review!

Follow-ups applied:

• Updated the PR body to match the template (incl. AI assistance disclosure).
• Simplified the @supports detection to a single ancestors().any(...) check (addressing the redundant filtering concern).
• Tweaked the changeset wording and added a @supports (font: ...) valid spec case.

Could you please re-review when you have time?

[codspeed-hq]

CodSpeed Performance Report

Merging this PR will not alter performance

_{Comparing LouisLau-art:fix/css-use-generic-font-names-in-supports (186f5ae) with main (fd33f86)}

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. ↩

[LouisLau-art]

Pushed an update to address the review feedback:

• The rule now only ignores feature declarations (the condition), not declarations inside the block.
• Added a regression case in to ensure is still flagged.
• Updated the PR description to use the PR template + corrected the summary/test plan.

Could you please re-review when you have a moment?

[LouisLau-art]

Follow-up update (addressing review feedback):

• The rule now only ignores @supports (...) feature declarations (the condition), not declarations inside the @supports { ... } block.
• Added a regression case in invalid.css to ensure @supports { a { font-family: Arial; } } is still flagged.
• Updated the PR description to use the PR template + corrected the summary/test plan.

Could you please re-review when you have a moment?

[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 167-176: Update the rustdoc comment examples around the
is_in_supports_feature_declaration function to use a fenced code block (triple
backticks) so they become proper doctests; replace the inline backtick example
text with a ```css fenced block containing the `@supports` example and any
necessary runnable assertions or comments so the doctest compiles and passes.
Ensure the narrative lines remain as comments or plain text inside the fenced
block and keep references to the `@supports` condition versus block behavior
intact.

[LouisLau-art]

Addressed the review note: updated the rustdoc around to use a fenced code block for the example. Also verified locally with .

[LouisLau-art]

Follow-up: updated the rustdoc around is_in_supports_feature_declaration to use a fenced code block for the @supports example. Also verified locally with cargo test -p biome_css_analyze.

Feedback addressed