feat(selector): support special chars in class names (#150)

[pranaygp]

Summary

Closes #150.

Tailwind-style class names containing :, /, or non-ASCII characters were not handled correctly:

• findSelector stopped at /, so bg-red-500/50 was cut off mid-word.
• findDefinition built a regex from the raw selector value, so md:flex would not match .md\:flex in compiled CSS (and : was unescaped at the regex level).
• The chained-suffix matcher used [\w-], which excluded escaped chars like \: or \/ in subsequent class/id components.

Changes

• server/src/core/findSelector.ts — drop / from the start-of-word boundary set; the existing loop already passed through : and non-ASCII chars.
• server/src/core/findDefinition.ts — introduce escapeSelectorForRegex that escapes regex meta-chars and emits \\?: / \\?/ so source classes like md:flex match compiled symbols like .md\:flex. Extend the chained-suffix character class to include \\, :, and /.
• tests/fixture/tailwind.css + tests/fixture/tailwind.html — new fixtures with Tailwind-style classes and a Unicode class name.
• tests/src/findSelector.test.ts + tests/src/findDefinition.test.ts — 8 new tests covering md:flex, bg-red-500/50, café, and style:sm (the example from the issue).

Test plan

• yarn build passes with zero TS errors.
• yarn test — full suite (32 tests, including 8 new ones) passes.
• yarn lint clean.
• Existing pseudo-class behavior (:hover, ::before) still recognized as pseudo, not class.

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR extends the selector parsing + definition lookup logic to better support Tailwind-style class names containing special characters (notably : and /) and adds fixtures/tests to cover these cases (including a Unicode class name).

Changes:

• Update findSelector word-boundary scanning so / can be part of a class token (e.g. bg-red-500/50).
• Update findDefinition regex construction to escape selector values correctly and to match compiled CSS escapes like \.md\:flex.
• Add Tailwind-oriented HTML/CSS fixtures plus new unit tests for md:flex, bg-red-500/50, style:sm, and café.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
server/src/core/findSelector.ts	Adjusts selector token expansion rules to allow / inside class names.
server/src/core/findDefinition.ts	Escapes selector values for regex matching and broadens chained-suffix matching for Tailwind escapes.
tests/src/findSelector.test.ts	Adds fixture-driven tests for special-character and Unicode class extraction.
tests/src/findDefinition.test.ts	Adds definition-lookup tests for escaped Tailwind-style selectors.
tests/fixture/tailwind.html	New HTML fixture containing Tailwind-like and Unicode class names.
tests/fixture/tailwind.css	New CSS fixture with escaped selector forms (e.g. .md\\:flex, .bg-red-500\\/50).

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[pranaygp]

Fixed in 7e05e2a. The backward scan now treats / as a boundary only when the previous-previous char is < — i.e. only in the </ closing-tag sequence — so </div> resolves to div and aligns with the HTML scanner's EndTag offset, while Tailwind slash-values like bg-red-500/50 keep flowing through. Added a </h1> test case to findSelector.test.ts (run across html/jsx/php fixtures) to lock the behavior down.

[pranaygp]

Fixed in 7e05e2a. The chained-suffix matcher now uses a Unicode-aware identifier class ([\p{L}\p{N}_\\:/-]) with the u flag on both symbolRegexp and fileRegexp, so chained selectors with non-ASCII names like .foo.café and h1.café resolve correctly. Two ancillary tweaks required by switching to u: (a) escapeSelectorForRegex no longer emits a backslash before : or / (they're not regex meta-chars, and identity escapes are a SyntaxError under u); (b) the pseudo-class char range was reordered from [\w-()] to [\w()-] so \w- isn't read as a range. Added .foo.café and h1.café rules to tailwind.css plus matching tests resolving foo and h1 against those chained rules.