empty bracketed lists are not null

src/value/mod.rs

@@ -115,7 +115,7 @@ impl Value {
             Self::BinaryOp(..) | Self::Paren(..) | Self::UnaryOp(..) => {
                 self.clone().eval(span)?.is_null(span)
             }
-            Self::List(v, ..) => Ok(v.iter().all(|f| f.is_null(span).unwrap())),
+            Self::List(v, _, Brackets::None) => Ok(v.iter().all(|f| f.is_null(span).unwrap())),
             _ => Ok(false),
         }
     }

tests/list.rs

@@ -313,3 +313,4 @@ test!(
     "a {\n  color: length(zip((a, b, c)));\n}\n",
     "a {\n  color: 3;\n}\n"
 );
+test!(empty_bracketed_list, "a {\n  empty: [];\n}\n");