[xiehuanyi]

[data-foo="ä" i] currently matches data-foo="Ä". The same non-ASCII folding affects all insensitive comparison operators and attributes whose default comparison is insensitive. Selectors require ASCII case-insensitive comparison, so these distinct non-ASCII characters must remain distinct.

Restrict folding to A–Z in string comparisons. Build explicit ASCII character pairs for regex-based comparisons instead of using JavaScript's Unicode-aware i flag. Regex metacharacters remain escaped. Existing ASCII-insensitive behavior is retained.

Validation: eight new cases fail before the fix. npm test passes 226 tests with one existing skipped test, including ESLint, TypeScript and Biome. Tests cover all operators, implicit HTML attribute comparison, exact non-ASCII matches, and literal regex characters. npm run build and git diff --check pass.

Prepared and tested with OpenAI Codex assistance.

Summary by CodeRabbit

• Bug Fixes
  • Case-insensitive attribute selectors now match ASCII letters without treating non-ASCII uppercase and lowercase characters as equivalent. This applies to equality, prefix, suffix, substring, word, and hyphen-prefix matching, including negated equality and implicit type matching.
  • Regex metacharacters in attribute values are matched literally by case-insensitive substring and word selectors. Case-sensitive matching remains unchanged.

[Copilot]

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[chatgpt-codex-connector]

Codex Review Summary: ✅ Completed

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-11-06T21:11:45.237248Z	bb3de07	New commits

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[coderabbitai]

No actionable comments were generated in the recent review.

Walkthrough

Case-insensitive attribute selector matching now folds ASCII uppercase letters only. Equality, hyphen, word, prefix, suffix, substring, and negated-equality selectors use this behavior. Tests cover non-ASCII distinctions, implicit type matching, and literal regex characters.

Changes: Attribute selector matching

Layer / File(s)	Summary
ASCII case-insensitive matching src/attributes.ts, test/attributes.ts	Case-insensitive selectors now fold ASCII letters only. Word and substring selectors use escaped patterns with explicit ASCII case alternatives. Tests check non-ASCII distinctions, implicit type matching, and literal regex characters.

Estimated code review effort: 2 (Simple) | ~12 minutes

Change: Bug fix

Suggested reviewers: nevandecoteau

Merge Risk: Minimal · up to bb3de

The ASCII-only matching change is mergeable after normal checks.

Pre-merge checks: 5

Check name	Status	Explanation
Title check		The title accurately describes the change to ASCII-only case-insensitive attribute comparisons.
Docstring Coverage		No eligible functions found in the changed files. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff with cyclomatic complexity of at least 2. Documentat…
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.
Description Check		Check skipped - CodeRabbit’s high-level summary is enabled.

Full details: Docstring Coverage

Explanation

No eligible functions found in the changed files. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff with cyclomatic complexity of at least 2. Documentation-only edits and deletions within surviving functions are included; unchanged diff context and fully deleted functions are excluded. Analyzed 0 functions across 2 files.

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_{A rabbit checks each letter bright
ASCII cases settle right
Regex metacharacters stay
Non-ASCII keeps its own way
The selectors match by day}

Recent review info

Run configuration

• Source mode: Auto
• Repository: Unavailable
• Branch: Unavailable
• File: No configuration file from this repository applied
• Commit: Unavailable
• Layers: Organization UI
• Review profile: ASSERTIVE
• Plan: Advanced
• Run ID: b05b19ba-0147-41e4-ad44-5e23517cbe7a

Commits

Reviewing files that changed from the base of the PR and between 258df45 and bb3de07.

Files selected for processing: 2

• src/attributes.ts
• test/attributes.ts

Included review availability: This review used your included allowance. Your plan provides up to 4 included reviews per hour; 3 remain after this review.

[cubic-dev-ai]

No issues found across 2 files

_{View guided diff | Re-trigger cubic}

[greptile-apps]

Confidence Score: 5/5

[Medium impact] The PR appears safe to merge.

Summary

Limits case-insensitive attribute comparisons to ASCII letters.

• Attribute selectors ignore case only for ASCII letters.

No actionable issues were found. Tests were not run during this review.

_{Reviews (2) · Last reviewed commit: "Merge latest master to resolve attribute..." · Reviewed by Greptile}