<===> input.scss
foo {
  foo: foo(());
}

<===> error
Error: () isn't a valid CSS value.
        on line 2 of input.scss
  Use --trace for backtrace.

<===> error-dart-sass
Error: () isn't a valid CSS value.
  ,
2 |   foo: foo(());
  |            ^^
  '
  input.scss 2:12  root stylesheet