Allow @for to include only styles

src/atrule.rs

@@ -164,19 +164,21 @@ impl AtRule {
                 };
                 let mut body = Vec::new();
                 let mut n = 1;
-                for tok in toks {
+                while let Some(tok) = toks.next() {
                     match tok.kind {
                         TokenKind::Symbol(Symbol::OpenCurlyBrace) => n += 1,
                         TokenKind::Symbol(Symbol::CloseCurlyBrace) => n -= 1,
                         TokenKind::Interpolation => n += 1,
                         _ => {}
                     }
-                    body.push(tok);
                     if n == 0 {
                         break;
                     }
+                    body.push(tok);
                 }
 
+                devour_whitespace_or_comment(toks);
+
                 let mut scope = scope.clone();
                 if from < to {
                     for i in from..(to + through) {

src/css.rs

@@ -145,8 +145,7 @@ impl Css {
                             writeln!(buf, "{}@{} {} {{", padding, u.name, u.params)?;
                         }
                         Css::from_stylesheet(StyleSheet::from_stmts(u.body.clone()))
-                            .pretty_print(buf, nesting + 1)
-                            .unwrap();
+                            .pretty_print(buf, nesting + 1)?;
                         writeln!(buf, "{}}}", padding)?;
                     }
                     _ => todo!(),

src/lib.rs

@@ -498,7 +498,10 @@ impl<'a> StyleSheetParser<'a> {
         while let Some(expr) = eat_expr(&mut self.lexer, scope, super_selector)? {
             match expr {
                 Expr::Style(s) => stmts.push(Stmt::Style(*s)),
-                Expr::AtRule(s) => stmts.push(Stmt::AtRule(s)),
+                Expr::AtRule(a) => match a {
+                    AtRule::For(s) => stmts.extend(s),
+                    r => stmts.push(Stmt::AtRule(r)),
+                },
                 Expr::Styles(s) => stmts.extend(s.into_iter().map(Stmt::Style)),
                 Expr::MixinDecl(name, mixin) => {
                     scope.insert_mixin(&name, *mixin);

src/value/parse.rs

@@ -160,7 +160,7 @@ impl Value {
         let kind = if let Some(tok) = toks.next() {
             tok.kind
         } else {
-            return Err("Unexpected EOF".into());
+            panic!("Unexpected EOF");
         };
         match kind {
             TokenKind::Number(val) => {

tests/for.rs

@@ -33,3 +33,8 @@ test!(
     "@for $x from 1 to 3 {\n  $limit: $x;\n\n  a {\n    color: $limit;\n  }\n}\n",
     "a {\n  color: 1;\n}\n\na {\n  color: 2;\n}\n"
 );
+test!(
+    for_styles,
+    "a {\n  @for $i from 1 to 3 {\n    color: $i;\n  }\n}\n",
+    "a {\n  color: 1;\n  color: 2;\n}\n"
+);