Pug: classes not extracted after a text line with an unbalanced `(`

[timmapme]

What version of Tailwind CSS are you using?

v4.3.3 (@tailwindcss/oxide 4.3.3)

What build tool (or framework if it abstracts the build tool) are you using?

Vite 8 with @tailwindcss/vite, Vue 3 SFCs with <template lang="pug">; reproduced with the bare Oxide Scanner too.

Reproduction

broken.pug:

p
  | (
  span.underline.font-bold(title="x") km
  | )

working.pug (same, but the text lines contain no bracket):

p
  | x
  span.underline.font-bold(title="x") km
  | x

const {Scanner} = require('@tailwindcss/oxide')
for (const f of ['broken.pug', 'working.pug'])
  console.log(f, new Scanner({sources: [{base: __dirname, pattern: f, negated: false}]}).scan()
    .filter(c => ['underline', 'font-bold'].includes(c)))

broken.pug   []
working.pug  [ 'font-bold', 'underline' ]

Describe your issue

A Pug text line containing an unbalanced opening bracket (here | (, which renders a literal "(") stops the
class shorthand on the next tag from being extracted, so those utilities silently get no CSS. Pug itself
renders the template correctly. A real-world case is wrapping a button in parentheses: | (, then
v-btn.px-0.normal-case(...), then | ).

The cause appears to be the bracket tracking in crates/oxide/src/extractor/pre_processors/pug.rs: the
BracketStack is kept across the whole file, so the ( in the text line is pushed and never matched.
While the stack is non-empty, . is no longer replaced with a space, so span.underline.font-bold stays a
single, invalid candidate. The tag's own attribute parens don't help: its ) pops only its own (.

The same happens inside Vue SFCs (<template lang="pug">), where only some of the classes are extracted.

A comment line behaves the same way: //- a bare "(" here before the tag reproduces it too.

Workaround: write the bracket as an HTML entity (| () or keep brackets balanced on the text line.

Possible fix: reset the bracket stack at line boundaries unless the line is inside an attribute list
(Pug attribute lists may span lines, so a plain per-line reset is not enough), or skip piped text (| ...)
and comment (//, //-) lines in the pre-processor.