Custom at-rules causes LibSass an error but not the Ruby version of Sass

[lozandier]

Problem

Unlike the recent versions of Ruby Sass, LibSass communicates a parsing/syntax error if a custom at-rule is used.

The following syntax demonstrates this (Ignore the CSS Mixin --foo & the incorrect output both LibSass & Sass currently outputs for it, will be addressed by another issue when it's time)

:root {
 --foo: red;
 --bar: {
   color: red;
   background: yellow;
 }
}

x-foo {
  border: 1px solid var(--foo);  
  @apply(--bar); // Breaks in LibSass but not RubySass
}

Screenshots of Correct & Problematic Output

Ruby Sass Output

LibSass output

[KittyGiraudel]

Seconded. Sass should allow custom directives for forward-compatibility.

[mgreter]

Minimized test case:

foo {
  @--bar(--baz);
}

Expected result:

foo {
  @--bar (--baz); }

[mgreter]

The original issue is solved with my latest WIP 3.3 branch, but there seems to be a side issue when the custom at_rule block is not preceded by some other declaration. Need to investigate further!

[lozandier]

@mgreter Why is the minimal test case not the following (unless it implicitly also allowing the following to be legal):

Minimized test case:

foo {
  @bar(--baz);
}

Expected result:

foo {
  @bar (--baz); }

[mgreter]

We now have a passing spec test since #1249 was merged 🎈