<===> input.scss
@function foo($bar) {
  @return $bar;
}

$foo: foo(#{});

<===> error
Error: Invalid CSS after "$foo: foo(#{": expected expression (e.g. 1px, bold), was "});"
        on line 5 of input.scss
  Use --trace for backtrace.

<===> error-dart-sass
Error: Expected expression.
  ,
5 | $foo: foo(#{});
  |           ^^
  '
  input.scss 5:11  root stylesheet