avoid cloning the entire scope

src/atrule/mixin.rs

@@ -1,4 +1,4 @@
-use crate::{args::FuncArgs, scope::Scopes, Token};
+use crate::{args::FuncArgs, Token};
 
 #[derive(Debug, Clone)]
 pub(crate) struct Mixin {
@@ -28,7 +28,6 @@ impl Mixin {
 pub(crate) struct Content {
     pub content: Option<Vec<Token>>,
     pub content_args: Option<FuncArgs>,
-    pub scopes: Scopes,
 }
 
 impl Content {
@@ -36,7 +35,6 @@ impl Content {
         Self {
             content: None,
             content_args: None,
-            scopes: Scopes::new(),
         }
     }
 }

src/lib.rs

@@ -157,6 +157,7 @@ pub fn from_path(p: &str) -> Result<String> {
         at_root: true,
         at_root_has_selector: false,
         extender: &mut Extender::new(empty_span),
+        content_scopes: &mut Scopes::new(),
     }
     .parse()
     .map_err(|e| raw_to_parse_error(&map, *e))?;
@@ -199,6 +200,7 @@ pub fn from_string(p: String) -> Result<String> {
         at_root: true,
         at_root_has_selector: false,
         extender: &mut Extender::new(empty_span),
+        content_scopes: &mut Scopes::new(),
     }
     .parse()
     .map_err(|e| raw_to_parse_error(&map, *e))?;
@@ -232,6 +234,7 @@ pub fn from_string(p: String) -> std::result::Result<String, JsValue> {
         at_root: true,
         at_root_has_selector: false,
         extender: &mut Extender::new(empty_span),
+        content_scopes: &mut Scopes::new(),
     }
     .parse()
     .map_err(|e| raw_to_parse_error(&map, *e).to_string())?;

src/parse/args.rs

@@ -357,6 +357,10 @@ impl<'a> Parser<'a> {
         mut args: CallArgs,
     ) -> SassResult<Scope> {
         let mut scope = Scope::new();
+        if fn_args.0.is_empty() {
+            args.max_args(0)?;
+            return Ok(scope);
+        }
         self.scopes.enter_new_scope();
         for (idx, arg) in fn_args.0.iter_mut().enumerate() {
             if arg.is_variadic {

src/parse/control_flow.rs

@@ -51,6 +51,7 @@ impl<'a> Parser<'a> {
                 at_root: self.at_root,
                 at_root_has_selector: self.at_root_has_selector,
                 extender: self.extender,
+                content_scopes: self.content_scopes,
             }
             .parse_stmt()?;
         } else {
@@ -108,6 +109,7 @@ impl<'a> Parser<'a> {
                                 at_root: self.at_root,
                                 at_root_has_selector: self.at_root_has_selector,
                                 extender: self.extender,
+                                content_scopes: self.content_scopes,
                             }
                             .parse_stmt()?;
                         } else {
@@ -134,6 +136,7 @@ impl<'a> Parser<'a> {
                                 at_root: self.at_root,
                                 at_root_has_selector: self.at_root_has_selector,
                                 extender: self.extender,
+                                content_scopes: self.content_scopes,
                             }
                             .parse_stmt();
                         }
@@ -312,6 +315,7 @@ impl<'a> Parser<'a> {
                     at_root: self.at_root,
                     at_root_has_selector: self.at_root_has_selector,
                     extender: self.extender,
+                    content_scopes: self.content_scopes,
                 }
                 .parse()?;
                 if !these_stmts.is_empty() {
@@ -332,6 +336,7 @@ impl<'a> Parser<'a> {
                         at_root: self.at_root,
                         at_root_has_selector: self.at_root_has_selector,
                         extender: self.extender,
+                        content_scopes: self.content_scopes,
                     }
                     .parse()?,
                 );
@@ -380,6 +385,7 @@ impl<'a> Parser<'a> {
                     at_root: self.at_root,
                     at_root_has_selector: self.at_root_has_selector,
                     extender: self.extender,
+                    content_scopes: self.content_scopes,
                 }
                 .parse()?;
                 if !these_stmts.is_empty() {
@@ -400,6 +406,7 @@ impl<'a> Parser<'a> {
                         at_root: self.at_root,
                         at_root_has_selector: self.at_root_has_selector,
                         extender: self.extender,
+                        content_scopes: self.content_scopes,
                     }
                     .parse()?,
                 );
@@ -496,6 +503,7 @@ impl<'a> Parser<'a> {
                     at_root: self.at_root,
                     at_root_has_selector: self.at_root_has_selector,
                     extender: self.extender,
+                    content_scopes: self.content_scopes,
                 }
                 .parse()?;
                 if !these_stmts.is_empty() {
@@ -516,6 +524,7 @@ impl<'a> Parser<'a> {
                         at_root: self.at_root,
                         at_root_has_selector: self.at_root_has_selector,
                         extender: self.extender,
+                        content_scopes: self.content_scopes,
                     }
                     .parse()?,
                 );

src/parse/function.rs

@@ -106,6 +106,7 @@ impl<'a> Parser<'a> {
             at_root: false,
             at_root_has_selector: self.at_root_has_selector,
             extender: self.extender,
+            content_scopes: self.content_scopes,
         }
         .parse()?;
 

src/parse/import.rs

@@ -90,6 +90,7 @@ impl<'a> Parser<'a> {
                     at_root: self.at_root,
                     at_root_has_selector: self.at_root_has_selector,
                     extender: self.extender,
+                    content_scopes: self.content_scopes,
                 }
                 .parse();
             }

src/parse/keyframes.rs

@@ -164,6 +164,7 @@ impl<'a> Parser<'a> {
                         at_root: self.at_root,
                         at_root_has_selector: self.at_root_has_selector,
                         extender: self.extender,
+                        content_scopes: self.content_scopes,
                     })
                     .parse_keyframes_selector()?;
 
@@ -193,6 +194,7 @@ impl<'a> Parser<'a> {
             at_root: false,
             at_root_has_selector: self.at_root_has_selector,
             extender: self.extender,
+            content_scopes: self.content_scopes,
         }
         .parse_stmt()?;
 

src/parse/mixin.rs

@@ -1,3 +1,5 @@
+use std::mem;
+
 use codemap::Spanned;
 
 use peekmore::PeekMore;
@@ -6,7 +8,6 @@ use crate::{
     args::{CallArgs, FuncArgs},
     atrule::{Content, Mixin},
     error::SassResult,
-    scope::Scopes,
     utils::read_until_closing_curly_brace,
     Token,
 };
@@ -121,30 +122,32 @@ impl<'a> Parser<'a> {
 
         let scope = self.eval_args(fn_args, args)?;
 
-        let mut new_scope = Scopes::new();
+        let mut new_scope = std::mem::take(self.content_scopes);
-        let mut entered_scope = false;
-        if declared_at_root {
-            new_scope.enter_scope(scope);
-        } else {
-            entered_scope = true;
-            self.scopes.enter_scope(scope);
-        };
 
         self.content.push(Content {
             content,
             content_args,
-            scopes: self.scopes.clone(),
         });
 
+        let mut scopes = if declared_at_root {
+            mem::take(&mut new_scope)
+        } else {
+            mem::take(self.scopes)
+        };
+
+        let mut content_scopes = if declared_at_root {
+            mem::take(self.scopes)
+        } else {
+            mem::take(&mut new_scope)
+        };
+
+        scopes.enter_scope(scope);
+
         let body = Parser {
             toks: &mut body.into_iter().peekmore(),
             map: self.map,
             path: self.path,
-            scopes: if declared_at_root {
+            scopes: &mut scopes,
-                &mut new_scope
-            } else {
-                self.scopes
-            },
             global_scope: self.global_scope,
             super_selectors: self.super_selectors,
             span_before: self.span_before,
@@ -153,12 +156,18 @@ impl<'a> Parser<'a> {
             at_root: false,
             at_root_has_selector: self.at_root_has_selector,
             extender: self.extender,
+            content_scopes: &mut content_scopes,
         }
         .parse()?;
 
         self.content.pop();
-        if entered_scope {
+        if declared_at_root {
-            self.scopes.exit_scope();
+            *self.scopes = content_scopes;
+            *self.content_scopes = scopes;
+        } else {
+            scopes.exit_scope();
+            *self.scopes = scopes;
+            *self.content_scopes = content_scopes;
         }
 
         Ok(body)
@@ -173,19 +182,14 @@ impl<'a> Parser<'a> {
                 .into());
         }
 
-        let mut scope = self
-            .content
-            .last()
-            .cloned()
-            .unwrap_or_else(Content::new)
-            .scopes;
         if let Some(Token { kind: '(', .. }) = self.toks.peek() {
             self.toks.next();
             let args = self.parse_call_args()?;
             if let Some(Some(content_args)) = self.content.last().map(|v| v.content_args.clone()) {
                 args.max_args(content_args.len())?;
 
-                scope.merge(self.eval_args(content_args, args)?);
+                let scope = self.eval_args(content_args, args)?;
+                self.content_scopes.merge(scope);
             } else {
                 args.max_args(0)?;
             }
@@ -197,7 +201,7 @@ impl<'a> Parser<'a> {
                     toks: &mut body.into_iter().peekmore(),
                     map: self.map,
                     path: self.path,
-                    scopes: &mut scope,
+                    scopes: self.content_scopes,
                     global_scope: self.global_scope,
                     super_selectors: self.super_selectors,
                     span_before: self.span_before,
@@ -206,6 +210,7 @@ impl<'a> Parser<'a> {
                     at_root: self.at_root,
                     at_root_has_selector: self.at_root_has_selector,
                     extender: self.extender,
+                    content_scopes: self.scopes,
                 }
                 .parse()?
             } else {

src/parse/mod.rs

@@ -70,6 +70,7 @@ pub(crate) struct Parser<'a> {
     pub path: &'a Path,
     pub global_scope: &'a mut Scope,
     pub scopes: &'a mut Scopes,
+    pub content_scopes: &'a mut Scopes,
     pub super_selectors: &'a mut NeverEmptyVec<Selector>,
     pub span_before: Span,
     pub content: &'a mut Vec<Content>,
@@ -357,6 +358,7 @@ impl<'a> Parser<'a> {
                 at_root: self.at_root,
                 at_root_has_selector: self.at_root_has_selector,
                 extender: self.extender,
+                content_scopes: self.content_scopes,
             },
             allows_parent,
             true,
@@ -583,6 +585,7 @@ impl<'a> Parser<'a> {
             at_root: false,
             at_root_has_selector: self.at_root_has_selector,
             extender: self.extender,
+            content_scopes: self.content_scopes,
         }
         .parse_stmt()?;
 
@@ -649,6 +652,7 @@ impl<'a> Parser<'a> {
             at_root: true,
             at_root_has_selector,
             extender: self.extender,
+            content_scopes: self.content_scopes,
         }
         .parse()?
         .into_iter()
@@ -688,6 +692,7 @@ impl<'a> Parser<'a> {
             at_root: self.at_root,
             at_root_has_selector: self.at_root_has_selector,
             extender: self.extender,
+            content_scopes: self.content_scopes,
         }
         .parse_selector(false, true, String::new())?;
 
@@ -764,6 +769,7 @@ impl<'a> Parser<'a> {
             at_root: false,
             at_root_has_selector: self.at_root_has_selector,
             extender: self.extender,
+            content_scopes: self.content_scopes,
         }
         .parse()?;
 

src/parse/value/parse.rs

@@ -195,6 +195,7 @@ impl<'a> Parser<'a> {
             at_root: self.at_root,
             at_root_has_selector: self.at_root_has_selector,
             extender: self.extender,
+            content_scopes: self.content_scopes,
         }
         .parse_value()
     }

src/value/mod.rs

@@ -444,6 +444,7 @@ impl Value {
             at_root: parser.at_root,
             at_root_has_selector: parser.at_root_has_selector,
             extender: parser.extender,
+            content_scopes: parser.content_scopes,
         }
         .parse_selector(allows_parent, true, String::new())
     }

tests/mixins.rs

@@ -399,3 +399,30 @@ test!(
     }",
     "a {\n  color: foo;\n  color: bar;\n}\n"
 );
+test!(
+    three_depth_of_content,
+    "@mixin foo($arg) {
+        @include bar {
+            color: $arg;
+        }
+    }
+
+    @mixin bar {
+        @include baz {
+          @content;
+        }
+    }
+
+    @mixin baz {
+        @content;
+    }
+
+    @mixin font-size($value) {
+      @include foo($value);
+    }
+
+    a {
+        @include font-size(1rem);
+    }",
+    "a {\n  color: 1rem;\n}\n"
+);