Segfault if a function definition has a css comment

[soulan]

@function text-contrast($bg-color, $dark-text: $dark-text-color, $light-text: $light-text-color) {
/*
$bg-brightness: round(red($bg-color) * 0.3) + (green($bg-color) * 0.59) + (blue($bg-color) * 0.11);
@if abs($bg-brightness) < 200 {
    @return $light-text;
} @else {
    @return $dark-text;
}
*/

@if use-dark-text($bg-color){
    @return $dark-text;
} @else {
    @return $light-text;
}

/*
$color-brightness: round((red($bg-color) * 300) + (green($bg-color) * 590) + (blue($bg-color) * 110) / 1000);
$light-text-brightness: round((red($light-text) * 300) + (green($light-text) * 590) + (blue($light-text) * 110) / 1000);
$dark-text-brightness: round((red($dark-text) * 300) + (green($dark-text) * 590) + (blue($dark-text) * 110) / 1000);

@if abs($color-brightness - $light-text-brightness) > abs($color-brightness - $dark-text-brightness) {
    @return $light-text;
} @else {
    @return $dark-text;
}
*/
}

@mixin contrasted-important($background-color, $dark-text: $dark-text-color, $light-text: $light-text-color){
background-color: $background-color !important;
color: text-contrast($background-color, $dark-text, $light-text) !important;
}

I've got these 2 mixins, when I call contrasted-important in this setup I get a segemntation fault

@mixin contrasted-important($background-color, $dark-text: $dark-text-color, $light-text: $light-text-color){
background-color: $background-color !important;
color: text-contrast($background-color, $dark-text, $light-text);
}

and in this setup the value of color gets

color: /*
$bg-brightness: round(red($bg-color) * 0.3) + (green($bg-color) * 0.59) + (blue($bg-color) * 0.11);
@if abs($bg-brightness) < 200 {
    @return $light-text;
} @else {
    @return $dark-text;
}
*/;

[xzyfer]

This is because css style comments /* */ are still parsed (somewhat). The errors described are likely due to the commented out code being invalid sass. Ideally we would fail gracefully though.

If you want to truly comment sass code you need to use sass line comments //.

[xzyfer]

Sassmeister gist for reference: http://sassmeister.com/gist/b83650c20ec46ac1246b

[xzyfer]

Reduced test case

@function foo() {
  /* $bar: 1; */
 @return true;
}

a {
  a: foo();
}

This cases Libsass to hang indefinitely.

[xzyfer]

Spec added sass/sass-spec#241.

[xzyfer]

This is fixed and will be in 3.2.