How to debug 'SassC::SyntaxError: Unknown error occurred' about sassc-rails

[bolandrm]

This is a probably a syntax error that Libsass doesn't do a good job of explaining.

Are you able to narrow this down at all? If your CSS is split into multiple files, can you incrementally add files until you figure out which part of the CSS is at fault?

If you can narrow it down to the particular CSS that is causing the problem, we can create a issue for Libsass.

[pkmiec]

Yes, I can attempt to do so. I will report what I find out.

[pkmiec]

I had this pattern,

$grid-classes: ();

@mixin generate($viewport) {
  $grid-classes: append($grid-classes, ..., comma);
  ...
}

@include generate(small);
@include generate(medium);
@include generate(large);

#{$grid-classes} {
 ...
}

which worked in sass / sass-rails.

The problem in sassc is that the global $grid-classes variable is not modified by the mixin. So #{$grid-classes} at the end is empty, which causes the Unknown error occurred error.

I'm not sure whether sass or sassc has the correct treatment of global variables inside of mixins. But I changed my code so that it works with both sass and sassc.

[bolandrm]

Thanks for the follow up. I'm going to close this - since it's a libsass issue. I'd encourage you to report this behavior over at https://github.com/sass/libsass/issues.