improve handling of newlines for @at-root

src/output.rs

@@ -80,6 +80,17 @@ impl Toplevel {
     }
 }
 
+fn set_group_end(group: &mut [Toplevel]) {
+    match group.last_mut() {
+        Some(Toplevel::RuleSet { is_group_end, .. })
+        | Some(Toplevel::Supports { is_group_end, .. })
+        | Some(Toplevel::Media { is_group_end, .. }) => {
+            *is_group_end = true;
+        }
+        _ => {}
+    }
+}
+
 #[derive(Debug, Clone)]
 enum BlockEntry {
     Style(Style),
@@ -206,7 +217,11 @@ impl Css {
                         Stmt::Return(..) => unreachable!(),
                         Stmt::AtRoot { body } => {
                             body.into_iter().try_for_each(|r| -> SassResult<()> {
-                                vals.append(&mut self.parse_stmt(r)?);
+                                let mut stmts = self.parse_stmt(r)?;
+
+                                set_group_end(&mut stmts);
+
+                                vals.append(&mut stmts);
                                 Ok(())
                             })?;
                         }
@@ -285,14 +300,7 @@ impl Css {
         for stmt in stmts {
             let mut v = self.parse_stmt(stmt)?;
 
-            match v.last_mut() {
-                Some(Toplevel::RuleSet { is_group_end, .. })
-                | Some(Toplevel::Supports { is_group_end, .. })
-                | Some(Toplevel::Media { is_group_end, .. }) => {
-                    *is_group_end = true;
-                }
-                _ => {}
-            }
+            set_group_end(&mut v);
 
             self.blocks.extend(v);
         }

src/parse/mod.rs

@@ -184,9 +184,8 @@ impl<'a> Parser<'a> {
                             if self.at_root {
                                 stmts.append(&mut self.parse_at_root()?);
                             } else {
-                                stmts.push(Stmt::AtRoot {
-                                    body: self.parse_at_root()?,
-                                });
+                                let body = self.parse_at_root()?;
+                                stmts.push(Stmt::AtRoot { body });
                             }
                         }
                         AtRuleKind::Error => {
@@ -780,11 +779,27 @@ impl<'a> Parser<'a> {
             _ => Some(Ok(s)),
         })
         .collect::<SassResult<Vec<Stmt>>>()?;
-        let mut stmts = vec![Stmt::RuleSet {
-            selector: at_rule_selector,
-            body: styles,
-        }];
-        stmts.extend(raw_stmts);
+
+        let stmts = if at_root_has_selector {
+            let mut body = styles;
+            body.extend(raw_stmts);
+
+            vec![Stmt::RuleSet {
+                body,
+                selector: at_rule_selector,
+            }]
+        } else {
+            if !styles.is_empty() {
+                return Err((
+                    "Found style at the toplevel inside @at-root.",
+                    self.span_before,
+                )
+                    .into());
+            }
+
+            raw_stmts
+        };
+
         Ok(stmts)
     }
 

tests/at-root.rs

@@ -66,8 +66,53 @@ test!(
     "a {}\n\n@at-root {\n    @-ms-viewport { width: device-width; }\n}\n",
     "@-ms-viewport {\n  width: device-width;\n}\n"
 );
+test!(
+    newline_between_style_rules_with_same_parent_but_first_is_in_at_root,
+    "a {
+      @at-root {
+        b {
+          color: red;
+        }
+      }
+    
+      b {
+        color: red;
+      }
+    }",
+    "b {\n  color: red;\n}\n\na b {\n  color: red;\n}\n"
+);
+test!(
+    no_newline_between_style_rules_when_there_exists_a_selector,
+    "@at-root a {
+      a {
+        color: red;
+      }
+    
+      a {
+        color: red;
+      }
+    }",
+    "a a {\n  color: red;\n}\na a {\n  color: red;\n}\n"
+);
+test!(
+    newline_between_style_rules_when_there_does_not_exist_a_selector,
+    "@at-root {
+      a {
+        color: red;
+      }
+    
+      a {
+        color: red;
+      }
+    }",
+    "a {\n  color: red;\n}\n\na {\n  color: red;\n}\n"
+);
 error!(
     #[ignore = "we do not currently validate missing closing curly braces"]
     missing_closing_curly_brace,
     "@at-root {", "Error: expected \"}\"."
 );
+error!(
+    style_at_toplevel_without_selector,
+    "@at-root { color: red; }", "Error: Found style at the toplevel inside @at-root."
+);