fix(es/transforms): Fix bugs (#1769)

swc_ecma_transforms_optimization:
 - `dce`: Mark references from decorator as usage. (denoland/deno#10789)

swc_ecma_transforms_proposal:
 - Allow using `super` in decorated class methods. (#846)

ecmascript/transforms/classes/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+authors = ["강동윤 <kdy1997.dev@gmail.com>"]
+description = "Helper for transforms for the swc project"
+documentation = "https://rustdoc.swc.rs/swc_ecma_transforms_classes/"
+edition = "2018"
+license = "Apache-2.0/MIT"
+name = "swc_ecma_transforms_classes"
+repository = "https://github.com/swc-project/swc.git"
+version = "0.1.0"
+
+[dependencies]
+swc_atoms = {version = "0.2.6", path = "../../../atoms"}
+swc_common = {version = "0.10.20", path = "../../../common"}
+swc_ecma_ast = {version = "0.45.0", path = "../../ast"}
+swc_ecma_transforms_base = {version = "0.15.5", path = "../base"}
+swc_ecma_utils = {version = "0.36.0", path = "../../utils"}
+swc_ecma_visit = {version = "0.31.0", path = "../../visit"}

ecmascript/transforms/classes/src/lib.rs

@@ -0,0 +1,22 @@
+use swc_common::DUMMY_SP;
+use swc_ecma_ast::*;
+use swc_ecma_transforms_base::helper;
+use swc_ecma_utils::ExprFactory;
+
+#[macro_use]
+pub mod macros;
+pub mod super_field;
+
+/// Creates
+///
+/// ```js
+/// Child.__proto__ || Object.getPrototypeOf(Child)
+/// ```
+pub fn get_prototype_of(obj: Expr) -> Expr {
+    Expr::Call(CallExpr {
+        span: DUMMY_SP,
+        callee: helper!(get_prototype_of, "getPrototypeOf"),
+        args: vec![obj.as_arg()],
+        type_args: Default::default(),
+    })
+}

ecmascript/transforms/classes/src/macros.rs

@@ -1,3 +1,5 @@
+/// Not intended for public use.
+#[macro_export]
 macro_rules! fold_only_key {
     () => {
         fn fold_class_member(&mut self, m: ClassMember) -> ClassMember {

ecmascript/transforms/classes/src/super_field.rs

@@ -23,7 +23,7 @@ use swc_ecma_visit::{noop_fold_type, Fold, FoldWith};
 ///
 /// _get(Child.prototype.__proto__ || Object.getPrototypeOf(Child.prototype),
 /// 'foo', this).call(this, a);
-pub(crate) struct SuperFieldAccessFolder<'a> {
+pub struct SuperFieldAccessFolder<'a> {
     pub class_name: &'a Ident,
 
     pub vars: &'a mut Vec<VarDeclarator>,

ecmascript/transforms/compat/Cargo.toml

@@ -6,7 +6,7 @@ edition = "2018"
 license = "Apache-2.0/MIT"
 name = "swc_ecma_transforms_compat"
 repository = "https://github.com/swc-project/swc.git"
-version = "0.17.7"
+version = "0.17.8"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
@@ -22,6 +22,7 @@ swc_atoms = {version = "0.2.5", path = "../../../atoms"}
 swc_common = {version = "0.10.16", path = "../../../common"}
 swc_ecma_ast = {version = "0.45.0", path = "../../ast"}
 swc_ecma_transforms_base = {version = "0.15.0", path = "../base"}
+swc_ecma_transforms_classes = {version = "0.1.0", path = "../classes"}
 swc_ecma_transforms_macros = {version = "0.2.1", path = "../macros"}
 swc_ecma_utils = {version = "0.36.0", path = "../../utils"}
 swc_ecma_visit = {version = "0.31.0", path = "../../visit"}

ecmascript/transforms/compat/src/es2015/classes/constructor.rs

@@ -1,9 +1,10 @@
-use super::get_prototype_of;
 use std::iter;
 use swc_atoms::JsWord;
 use swc_common::{Mark, DUMMY_SP};
 use swc_ecma_ast::*;
 use swc_ecma_transforms_base::helper;
+use swc_ecma_transforms_classes::fold_only_key;
+use swc_ecma_transforms_classes::get_prototype_of;
 use swc_ecma_utils::quote_ident;
 use swc_ecma_utils::ExprFactory;
 use swc_ecma_visit::noop_visit_type;

ecmascript/transforms/compat/src/es2015/classes/mod.rs

@@ -1,4 +1,3 @@
-pub(crate) use self::super_field::SuperFieldAccessFolder;
 use self::{
     constructor::{
         constructor_fn, make_possible_return_value, replace_this_in_constructor, ConstructorFolder,
@@ -14,6 +13,7 @@ use swc_ecma_ast::*;
 use swc_ecma_transforms_base::helper;
 use swc_ecma_transforms_base::native::is_native;
 use swc_ecma_transforms_base::perf::Check;
+use swc_ecma_transforms_classes::super_field::SuperFieldAccessFolder;
 use swc_ecma_transforms_macros::fast_path;
 use swc_ecma_utils::quote_expr;
 use swc_ecma_utils::quote_str;
@@ -25,11 +25,8 @@ use swc_ecma_utils::{private_ident, quote_ident};
 use swc_ecma_visit::noop_visit_type;
 use swc_ecma_visit::{noop_fold_type, Fold, FoldWith, Node, Visit, VisitWith};
 
-#[macro_use]
-mod macros;
 mod constructor;
 mod prop_name;
-mod super_field;
 
 pub fn classes<C>(comments: Option<C>) -> impl Fold
 where
@@ -864,20 +861,6 @@ where
     }
 }
 
-/// Creates
-///
-/// ```js
-/// Child.__proto__ || Object.getPrototypeOf(Child)
-/// ```
-fn get_prototype_of(obj: Expr) -> Expr {
-    Expr::Call(CallExpr {
-        span: DUMMY_SP,
-        callee: helper!(get_prototype_of, "getPrototypeOf"),
-        args: vec![obj.as_arg()],
-        type_args: Default::default(),
-    })
-}
-
 fn inject_class_call_check(c: &mut Vec<Stmt>, name: Ident) {
     let class_call_check = CallExpr {
         span: DUMMY_SP,

ecmascript/transforms/compat/src/es2020/class_properties.rs

@@ -4,7 +4,6 @@ use self::{
     this_in_static::ThisInStaticFolder,
     used_name::{UsedNameCollector, UsedNameRenamer},
 };
-use crate::es2015::classes::SuperFieldAccessFolder;
 use std::{collections::HashSet, mem::take};
 use swc_atoms::JsWord;
 use swc_common::SyntaxContext;
@@ -12,6 +11,7 @@ use swc_common::{util::move_map::MoveMap, Mark, Spanned, DUMMY_SP};
 use swc_ecma_ast::*;
 use swc_ecma_transforms_base::helper;
 use swc_ecma_transforms_base::perf::Check;
+use swc_ecma_transforms_classes::super_field::SuperFieldAccessFolder;
 use swc_ecma_transforms_macros::fast_path;
 use swc_ecma_utils::private_ident;
 use swc_ecma_utils::quote_ident;

ecmascript/transforms/optimization/Cargo.toml

@@ -6,7 +6,7 @@ edition = "2018"
 license = "Apache-2.0/MIT"
 name = "swc_ecma_transforms_optimization"
 repository = "https://github.com/swc-project/swc.git"
-version = "0.20.1"
+version = "0.20.2"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]

ecmascript/transforms/optimization/src/simplify/dce/mod.rs

@@ -204,6 +204,24 @@ impl VisitMut for Dce<'_> {
     preserve!(visit_mut_break_stmt, BreakStmt);
     preserve!(visit_mut_continue_stmt, ContinueStmt);
 
+    fn visit_mut_bin_expr(&mut self, node: &mut BinExpr) {
+        if self.is_marked(node.span) {
+            return;
+        }
+
+        node.visit_mut_children_with(self);
+
+        if self.marking_phase
+            || self.is_marked(node.left.span())
+            || self.is_marked(node.right.span())
+        {
+            node.span = node.span.apply_mark(self.config.used_mark);
+
+            self.mark(&mut node.left);
+            self.mark(&mut node.right);
+        }
+    }
+
     fn visit_mut_block_stmt(&mut self, node: &mut BlockStmt) {
         if self.is_marked(node.span) {
             return;
@@ -216,6 +234,40 @@ impl VisitMut for Dce<'_> {
         }
     }
 
+    fn visit_mut_call_expr(&mut self, node: &mut CallExpr) {
+        if self.is_marked(node.span) {
+            return;
+        }
+
+        node.visit_mut_children_with(self);
+
+        if self.marking_phase
+            || self.is_marked(node.callee.span())
+            || node.args.iter().any(|arg| self.is_marked(arg.expr.span()))
+        {
+            node.span = node.span.apply_mark(self.config.used_mark);
+
+            self.mark(&mut node.callee);
+            self.mark(&mut node.args);
+        }
+    }
+
+    fn visit_mut_class_decl(&mut self, node: &mut ClassDecl) {
+        if self.is_marked(node.span()) {
+            return;
+        }
+        node.visit_mut_children_with(self);
+
+        if self.marking_phase
+            || self.included.contains(&node.ident.to_id())
+            || self.is_marked(node.ident.span())
+            || self.is_marked(node.class.span())
+        {
+            self.mark(&mut node.ident);
+            self.mark(&mut node.class);
+        }
+    }
+
     fn visit_mut_do_while_stmt(&mut self, node: &mut DoWhileStmt) {
         if self.is_marked(node.span) {
             return;
@@ -500,6 +552,13 @@ impl VisitMut for Dce<'_> {
         }
     }
 
+    fn visit_mut_module_items(&mut self, n: &mut Vec<ModuleItem>) {
+        self.visit_mut_stmt_like(n)
+    }
+
+    normal!(visit_mut_throw_stmt, ThrowStmt, arg);
+    normal!(visit_mut_try_stmt, TryStmt, block, handler, finalizer);
+
     fn visit_mut_named_export(&mut self, node: &mut NamedExport) {
         if self.is_marked(node.span) {
             return;
@@ -520,6 +579,26 @@ impl VisitMut for Dce<'_> {
         }
     }
 
+    fn visit_mut_new_expr(&mut self, node: &mut NewExpr) {
+        if self.is_marked(node.span) {
+            return;
+        }
+
+        node.span = node.span.apply_mark(self.config.used_mark);
+
+        self.mark(&mut node.callee);
+        self.mark(&mut node.args);
+    }
+
+    fn visit_mut_private_name(&mut self, _: &mut PrivateName) {}
+
+    fn visit_mut_prop_name(&mut self, n: &mut PropName) {
+        match n {
+            PropName::Computed(_) => n.visit_mut_children_with(self),
+            _ => {}
+        }
+    }
+
     fn visit_mut_return_stmt(&mut self, node: &mut ReturnStmt) {
         if self.is_marked(node.span) {
             return;
@@ -529,6 +608,14 @@ impl VisitMut for Dce<'_> {
         self.mark(&mut node.arg);
     }
 
+    fn visit_mut_stmts(&mut self, n: &mut Vec<Stmt>) {
+        if !self.decl_dropping_phase {
+            n.visit_mut_children_with(self);
+            return;
+        }
+        self.visit_mut_stmt_like(n)
+    }
+
     fn visit_mut_switch_case(&mut self, node: &mut SwitchCase) {
         if self.is_marked(node.span) {
             return;
@@ -566,8 +653,19 @@ impl VisitMut for Dce<'_> {
         }
     }
 
-    normal!(visit_mut_throw_stmt, ThrowStmt, arg);
-    normal!(visit_mut_try_stmt, TryStmt, block, handler, finalizer);
+    fn visit_mut_unary_expr(&mut self, node: &mut UnaryExpr) {
+        if self.is_marked(node.span) {
+            return;
+        }
+
+        node.visit_mut_children_with(self);
+
+        if self.marking_phase || self.is_marked(node.arg.span()) {
+            node.span = node.span.apply_mark(self.config.used_mark);
+
+            self.mark(&mut node.arg);
+        }
+    }
 
     fn visit_mut_update_expr(&mut self, node: &mut UpdateExpr) {
         if self.is_marked(node.span) {
@@ -578,18 +676,6 @@ impl VisitMut for Dce<'_> {
         self.mark(&mut node.arg);
     }
 
-    fn visit_mut_var_declarator(&mut self, d: &mut VarDeclarator) {
-        if self.is_marked(d.span) {
-            return;
-        }
-
-        d.visit_mut_children_with(self);
-
-        if self.is_marked(d.name.span()) || self.is_marked(d.init.span()) {
-            d.span = d.span.apply_mark(self.config.used_mark);
-        }
-    }
-
     fn visit_mut_var_decl(&mut self, mut var: &mut VarDecl) {
         if self.is_marked(var.span) {
             return;
@@ -622,6 +708,18 @@ impl VisitMut for Dce<'_> {
         var.span = var.span.apply_mark(self.config.used_mark);
     }
 
+    fn visit_mut_var_declarator(&mut self, d: &mut VarDeclarator) {
+        if self.is_marked(d.span) {
+            return;
+        }
+
+        d.visit_mut_children_with(self);
+
+        if self.is_marked(d.name.span()) || self.is_marked(d.init.span()) {
+            d.span = d.span.apply_mark(self.config.used_mark);
+        }
+    }
+
     fn visit_mut_while_stmt(&mut self, node: &mut WhileStmt) {
         if self.is_marked(node.span) {
             return;
@@ -637,104 +735,6 @@ impl VisitMut for Dce<'_> {
         }
     }
 
-    fn visit_mut_unary_expr(&mut self, node: &mut UnaryExpr) {
-        if self.is_marked(node.span) {
-            return;
-        }
-
-        node.visit_mut_children_with(self);
-
-        if self.marking_phase || self.is_marked(node.arg.span()) {
-            node.span = node.span.apply_mark(self.config.used_mark);
-
-            self.mark(&mut node.arg);
-        }
-    }
-
-    fn visit_mut_bin_expr(&mut self, node: &mut BinExpr) {
-        if self.is_marked(node.span) {
-            return;
-        }
-
-        node.visit_mut_children_with(self);
-
-        if self.marking_phase
-            || self.is_marked(node.left.span())
-            || self.is_marked(node.right.span())
-        {
-            node.span = node.span.apply_mark(self.config.used_mark);
-
-            self.mark(&mut node.left);
-            self.mark(&mut node.right);
-        }
-    }
-
-    fn visit_mut_new_expr(&mut self, node: &mut NewExpr) {
-        if self.is_marked(node.span) {
-            return;
-        }
-
-        node.span = node.span.apply_mark(self.config.used_mark);
-
-        self.mark(&mut node.callee);
-        self.mark(&mut node.args);
-    }
-
-    fn visit_mut_call_expr(&mut self, node: &mut CallExpr) {
-        if self.is_marked(node.span) {
-            return;
-        }
-
-        node.visit_mut_children_with(self);
-
-        if self.marking_phase
-            || self.is_marked(node.callee.span())
-            || node.args.iter().any(|arg| self.is_marked(arg.expr.span()))
-        {
-            node.span = node.span.apply_mark(self.config.used_mark);
-
-            self.mark(&mut node.callee);
-            self.mark(&mut node.args);
-        }
-    }
-
-    fn visit_mut_module_items(&mut self, n: &mut Vec<ModuleItem>) {
-        self.visit_mut_stmt_like(n)
-    }
-
-    fn visit_mut_stmts(&mut self, n: &mut Vec<Stmt>) {
-        if !self.decl_dropping_phase {
-            n.visit_mut_children_with(self);
-            return;
-        }
-        self.visit_mut_stmt_like(n)
-    }
-
-    fn visit_mut_private_name(&mut self, _: &mut PrivateName) {}
-
-    fn visit_mut_prop_name(&mut self, n: &mut PropName) {
-        match n {
-            PropName::Computed(_) => n.visit_mut_children_with(self),
-            _ => {}
-        }
-    }
-
-    fn visit_mut_class_decl(&mut self, node: &mut ClassDecl) {
-        if self.is_marked(node.span()) {
-            return;
-        }
-        node.visit_mut_children_with(self);
-
-        if self.marking_phase
-            || self.included.contains(&node.ident.to_id())
-            || self.is_marked(node.ident.span())
-            || self.is_marked(node.class.span())
-        {
-            self.mark(&mut node.ident);
-            self.mark(&mut node.class);
-        }
-    }
-
     // ---- ---- ----- ---- -----
     // If Spanned::span is synthesized, we should some work
 
@@ -919,9 +919,10 @@ impl Dce<'_> {
 
     pub fn has_marked_elem<T>(&self, n: &[T]) -> bool
     where
-        T: Spanned,
+        T: Spanned + IsDecorator,
     {
-        n.iter().any(|n| self.is_marked(n.span()))
+        n.iter()
+            .any(|n| T::is_decorator() || self.is_marked(n.span()))
     }
 
     pub fn should_preserve_export(&self, i: &JsWord) -> bool {
@@ -980,3 +981,59 @@ impl Dce<'_> {
         self.decl_dropping_phase = old;
     }
 }
+
+trait IsDecorator {
+    fn is_decorator() -> bool;
+}
+
+impl<T> IsDecorator for Option<T>
+where
+    T: IsDecorator,
+{
+    fn is_decorator() -> bool {
+        T::is_decorator()
+    }
+}
+
+impl<T> IsDecorator for Box<T>
+where
+    T: IsDecorator,
+{
+    fn is_decorator() -> bool {
+        T::is_decorator()
+    }
+}
+
+impl IsDecorator for Decorator {
+    fn is_decorator() -> bool {
+        true
+    }
+}
+
+macro_rules! not_decorator {
+    ($T:ty) => {
+        impl IsDecorator for $T {
+            fn is_decorator() -> bool {
+                false
+            }
+        }
+    };
+
+    ($($T:ty,)*) => {
+        $(
+            not_decorator!($T);
+        )*
+    };
+}
+
+not_decorator!(
+    ExprOrSpread,
+    Pat,
+    ClassMember,
+    ParamOrTsParamProp,
+    PropOrSpread,
+    Prop,
+    SpreadElement,
+    ObjectPatProp,
+    Expr,
+);

ecmascript/transforms/optimization/tests/dce/deno-18789/case1/input.js

@@ -0,0 +1,6 @@
+@decorator
+class Class { }
+
+function decorator(cls) {
+    console.log(cls.name);
+}

ecmascript/transforms/optimization/tests/dce/deno-18789/case1/output.full.js

@@ -0,0 +1,6 @@
+@decorator
+class Class {
+}
+function decorator(cls) {
+    console.log(cls.name);
+}

ecmascript/transforms/optimization/tests/dce/deno-18789/case1/output.js

@@ -0,0 +1,6 @@
+@decorator
+class Class {
+}
+function decorator(cls) {
+    console.log(cls.name);
+}

ecmascript/transforms/optimization/tests/fixture.rs

@@ -12,6 +12,7 @@ fn dce_single_pass(input: PathBuf) {
 
     test_fixture(
         Syntax::Es(EsConfig {
+            decorators: true,
             dynamic_import: true,
             ..Default::default()
         }),
@@ -27,6 +28,7 @@ fn dce_repeated(input: PathBuf) {
 
     test_fixture(
         Syntax::Es(EsConfig {
+            decorators: true,
             dynamic_import: true,
             ..Default::default()
         }),

ecmascript/transforms/proposal/Cargo.toml

@@ -25,6 +25,7 @@ swc_ecma_ast = {version = "0.45.0", path = "../../ast"}
 swc_ecma_loader = {version = "0.6.0", path = "../../loader", optional = true}
 swc_ecma_parser = {version = "0.57.0", path = "../../parser"}
 swc_ecma_transforms_base = {version = "0.15.0", path = "../base"}
+swc_ecma_transforms_classes = {version = "0.1.0", path = "../classes"}
 swc_ecma_utils = {version = "0.36.0", path = "../../utils"}
 swc_ecma_visit = {version = "0.31.0", path = "../../visit"}
 

ecmascript/transforms/proposal/src/decorators.rs

@@ -1,9 +1,12 @@
 use either::Either;
 use serde::Deserialize;
 use std::iter;
+use std::mem::take;
 use swc_common::{Spanned, DUMMY_SP};
 use swc_ecma_ast::*;
 use swc_ecma_transforms_base::helper;
+use swc_ecma_transforms_classes::super_field::SuperFieldAccessFolder;
+use swc_ecma_utils::prepend;
 use swc_ecma_utils::private_ident;
 use swc_ecma_utils::quote_ident;
 use swc_ecma_utils::quote_str;
@@ -64,6 +67,7 @@ pub fn decorators(c: Config) -> impl Fold {
         }
         Either::Right(Decorators {
             is_in_strict: false,
+            vars: Default::default(),
         })
     }
 }
@@ -79,6 +83,8 @@ pub struct Config {
 #[derive(Debug, Default)]
 struct Decorators {
     is_in_strict: bool,
+
+    vars: Vec<VarDeclarator>,
 }
 
 impl Fold for Decorators {
@@ -243,12 +249,25 @@ impl Fold for Decorators {
         });
 
         self.is_in_strict = old_strict;
+
+        if !self.vars.is_empty() {
+            prepend(
+                &mut buf,
+                ModuleItem::Stmt(Stmt::Decl(Decl::Var(VarDecl {
+                    span: DUMMY_SP,
+                    kind: VarDeclKind::Var,
+                    declare: false,
+                    decls: take(&mut self.vars),
+                }))),
+            )
+        }
+
         buf
     }
 }
 
 impl Decorators {
-    fn fold_class_inner(&self, ident: Ident, mut class: Class) -> Expr {
+    fn fold_class_inner(&mut self, ident: Ident, mut class: Class) -> Expr {
         let initialize = private_ident!("_initialize");
         let super_class_ident = match class.super_class {
             Some(ref expr) => Some(alias_ident_for(expr, "_super")),
@@ -324,9 +343,26 @@ impl Decorators {
             }
         };
 
+        let mut vars = vec![];
+
         macro_rules! fold_method {
             ($method:expr, $fn_name:expr, $key_prop_value:expr) => {{
                 let fn_name = $fn_name;
+                let method = $method;
+
+                let mut folder = SuperFieldAccessFolder {
+                    class_name: &ident,
+                    vars: &mut vars,
+                    constructor_this_mark: None,
+                    is_static: method.is_static,
+                    folding_constructor: true,
+                    in_nested_scope: false,
+                    in_injected_define_property_call: false,
+                    this_alias_mark: None,
+                };
+
+                let method = method.fold_with(&mut folder);
+
                 //   kind: "method",
                 //   key: getKeyJ(),
                 //   value: function () {
@@ -339,7 +375,7 @@ impl Decorators {
                             KeyValueProp {
                                 key: PropName::Ident(quote_ident!("kind")),
                                 value: Box::new(Expr::Lit(Lit::Str(quote_str!(
-                                    match $method.kind {
+                                    match method.kind {
                                         MethodKind::Method => "method",
                                         MethodKind::Getter => "get",
                                         MethodKind::Setter => "set",
@@ -347,7 +383,7 @@ impl Decorators {
                                 )))),
                             },
                         ))))
-                        .chain(if $method.is_static {
+                        .chain(if method.is_static {
                             Some(PropOrSpread::Prop(Box::new(Prop::KeyValue(KeyValueProp {
                                 key: PropName::Ident(quote_ident!("static")),
                                 value: Box::new(Expr::Lit(Lit::Bool(Bool {
@@ -360,14 +396,14 @@ impl Decorators {
                         })
                         .chain({
                             //
-                            if $method.function.decorators.is_empty() {
+                            if method.function.decorators.is_empty() {
                                 None
                             } else {
                                 Some(PropOrSpread::Prop(Box::new(Prop::KeyValue(KeyValueProp {
                                     key: PropName::Ident(quote_ident!("decorators")),
                                     value: Box::new(Expr::Array(ArrayLit {
                                         span: DUMMY_SP,
-                                        elems: $method
+                                        elems: method
                                             .function
                                             .decorators
                                             .into_iter()
@@ -392,7 +428,7 @@ impl Decorators {
                                         ident: fn_name.map(IdentExt::private),
                                         function: Function {
                                             decorators: vec![],
-                                            ..$method.function
+                                            ..method.function
                                         },
                                     }
                                     .into(),
@@ -420,7 +456,8 @@ impl Decorators {
                             PropName::Str(ref s) => Some(Ident::new(s.value.clone(), s.span)),
                             _ => None,
                         };
-                        let key_prop_value = Box::new(prop_name_to_expr_value(method.key));
+                        let key_prop_value = Box::new(prop_name_to_expr_value(method.key.clone()));
+
                         fold_method!(method, fn_name, key_prop_value)
                     }
                     ClassMember::PrivateMethod(method) => {
@@ -430,7 +467,7 @@ impl Decorators {
                         );
                         let key_prop_value = Box::new(Expr::Lit(Lit::Str(Str {
                             span: method.key.id.span,
-                            value: method.key.id.sym,
+                            value: method.key.id.sym.clone(),
                             has_escape: false,
                             kind: StrKind::Normal {
                                 contains_quote: false,
@@ -537,6 +574,8 @@ impl Decorators {
             .map(Some)
             .collect();
 
+        self.vars.extend(vars);
+
         Expr::Call(make_decorate_call(
             class.decorators,
             iter::once({

ecmascript/transforms/tests/decorators.rs

@@ -5736,3 +5736,71 @@ test!(
   }) || _class) || _class) || _class) || _class;
   "#
 );
+
+test!(
+    ts(),
+    |_| decorators(decorators::Config {
+        ..Default::default()
+    }),
+    issue_846_1,
+    "
+    class SomeClass {
+      @dec
+      someMethod() {}
+    }
+    
+    class OtherClass extends SomeClass {
+      @dec
+      anotherMethod() {
+        super.someMethod()
+      }
+    }
+    ",
+    "
+    let SomeClass = _decorate([], function(_initialize) {
+          class SomeClass {
+              constructor(){
+                  _initialize(this);
+              }
+          }
+          return {
+              F: SomeClass,
+              d: [
+                  {
+                      kind: 'method',
+                      decorators: [
+                          dec
+                      ],
+                      key: 'someMethod',
+                      value: function someMethod() {
+                      }
+                  }
+              ]
+          };
+      });
+      let OtherClass = _decorate([], function(_initialize, _SomeClass) {
+          class OtherClass extends _SomeClass {
+              constructor(...args){
+                  super(...args);
+                  _initialize(this);
+              }
+          }
+          return {
+              F: OtherClass,
+              d: [
+                  {
+                      kind: 'method',
+                      decorators: [
+                          dec
+                      ],
+                      key: 'anotherMethod',
+                      value: function anotherMethod() {
+                          _get(_getPrototypeOf(OtherClass.prototype), 'someMethod', \
+     this).call(this);
+                      }
+                  }
+              ]
+          };
+      }, SomeClass);
+    "
+);

package.json

@@ -1,6 +1,6 @@
 {
     "name": "@swc/core",
-    "version": "1.2.59",
+    "version": "1.2.60",
     "description": "Super-fast alternative for babel",
     "homepage": "https://swc.rs",
     "main": "./index.js",

tests/fixture/issue-846/case1/input/.swcrc

@@ -0,0 +1,8 @@
+{
+    "jsc": {
+        "parser": {
+            "syntax": "ecmascript",
+            "decorators": true
+        }
+    }
+}

tests/fixture/issue-846/case1/input/index.js

@@ -0,0 +1,11 @@
+class SomeClass {
+    @dec
+    someMethod() { }
+}
+
+class OtherClass extends SomeClass {
+    @dec
+    anotherMethod() {
+        super.someMethod()
+    }
+}

tests/fixture/issue-846/case1/output/index.js

@@ -0,0 +1,481 @@
+function _arrayWithHoles(arr) {
+    if (Array.isArray(arr)) return arr;
+}
+function _assertThisInitialized(self) {
+    if (self === void 0) {
+        throw new ReferenceError("this hasn't been initialised - super() hasn't been called");
+    }
+    return self;
+}
+function _classCallCheck(instance, Constructor) {
+    if (!(instance instanceof Constructor)) {
+        throw new TypeError("Cannot call a class as a function");
+    }
+}
+function _decorate(decorators, factory, superClass) {
+    var r = factory(function initialize(O) {
+        _initializeInstanceElements(O, decorated.elements);
+    }, superClass);
+    var decorated = _decorateClass(_coalesceClassElements(r.d.map(_createElementDescriptor)), decorators);
+    _initializeClassElements(r.F, decorated.elements);
+    return _runClassFinishers(r.F, decorated.finishers);
+}
+function _createElementDescriptor(def) {
+    var key = _toPropertyKey(def.key);
+    var descriptor;
+    if (def.kind === "method") {
+        descriptor = {
+            value: def.value,
+            writable: true,
+            configurable: true,
+            enumerable: false
+        };
+        Object.defineProperty(def.value, "name", {
+            value: _typeof(key) === "symbol" ? "" : key,
+            configurable: true
+        });
+    } else if (def.kind === "get") {
+        descriptor = {
+            get: def.value,
+            configurable: true,
+            enumerable: false
+        };
+    } else if (def.kind === "set") {
+        descriptor = {
+            set: def.value,
+            configurable: true,
+            enumerable: false
+        };
+    } else if (def.kind === "field") {
+        descriptor = {
+            configurable: true,
+            writable: true,
+            enumerable: true
+        };
+    }
+    var element = {
+        kind: def.kind === "field" ? "field" : "method",
+        key: key,
+        placement: def.static ? "static" : def.kind === "field" ? "own" : "prototype",
+        descriptor: descriptor
+    };
+    if (def.decorators) element.decorators = def.decorators;
+    if (def.kind === "field") element.initializer = def.value;
+    return element;
+}
+function _coalesceGetterSetter(element, other) {
+    if (element.descriptor.get !== undefined) {
+        other.descriptor.get = element.descriptor.get;
+    } else {
+        other.descriptor.set = element.descriptor.set;
+    }
+}
+function _coalesceClassElements(elements) {
+    var newElements = [];
+    var isSameElement = function isSameElement(other) {
+        return other.kind === "method" && other.key === element.key && other.placement === element.placement;
+    };
+    for(var i = 0; i < elements.length; i++){
+        var element = elements[i];
+        var other;
+        if (element.kind === "method" && (other = newElements.find(isSameElement))) {
+            if (_isDataDescriptor(element.descriptor) || _isDataDescriptor(other.descriptor)) {
+                if (_hasDecorators(element) || _hasDecorators(other)) {
+                    throw new ReferenceError("Duplicated methods (" + element.key + ") can't be decorated.");
+                }
+                other.descriptor = element.descriptor;
+            } else {
+                if (_hasDecorators(element)) {
+                    if (_hasDecorators(other)) {
+                        throw new ReferenceError("Decorators can't be placed on different accessors with for " + "the same property (" + element.key + ").");
+                    }
+                    other.decorators = element.decorators;
+                }
+                _coalesceGetterSetter(element, other);
+            }
+        } else {
+            newElements.push(element);
+        }
+    }
+    return newElements;
+}
+function _hasDecorators(element) {
+    return element.decorators && element.decorators.length;
+}
+function _isDataDescriptor(desc) {
+    return desc !== undefined && !(desc.value === undefined && desc.writable === undefined);
+}
+function _initializeClassElements(F, elements) {
+    var proto = F.prototype;
+    [
+        "method",
+        "field"
+    ].forEach(function(kind) {
+        elements.forEach(function(element) {
+            var placement = element.placement;
+            if (element.kind === kind && (placement === "static" || placement === "prototype")) {
+                var receiver = placement === "static" ? F : proto;
+                _defineClassElement(receiver, element);
+            }
+        });
+    });
+}
+function _initializeInstanceElements(O, elements) {
+    [
+        "method",
+        "field"
+    ].forEach(function(kind) {
+        elements.forEach(function(element) {
+            if (element.kind === kind && element.placement === "own") {
+                _defineClassElement(O, element);
+            }
+        });
+    });
+}
+function _defineClassElement(receiver, element) {
+    var descriptor = element.descriptor;
+    if (element.kind === "field") {
+        var initializer = element.initializer;
+        descriptor = {
+            enumerable: descriptor.enumerable,
+            writable: descriptor.writable,
+            configurable: descriptor.configurable,
+            value: initializer === void 0 ? void 0 : initializer.call(receiver)
+        };
+    }
+    Object.defineProperty(receiver, element.key, descriptor);
+}
+function _decorateClass(elements, decorators) {
+    var newElements = [];
+    var finishers = [];
+    var placements = {
+        static: [],
+        prototype: [],
+        own: []
+    };
+    elements.forEach(function(element) {
+        _addElementPlacement(element, placements);
+    });
+    elements.forEach(function(element) {
+        if (!_hasDecorators(element)) return newElements.push(element);
+        var elementFinishersExtras = _decorateElement(element, placements);
+        newElements.push(elementFinishersExtras.element);
+        newElements.push.apply(newElements, elementFinishersExtras.extras);
+        finishers.push.apply(finishers, elementFinishersExtras.finishers);
+    });
+    if (!decorators) {
+        return {
+            elements: newElements,
+            finishers: finishers
+        };
+    }
+    var result = _decorateConstructor(newElements, decorators);
+    finishers.push.apply(finishers, result.finishers);
+    result.finishers = finishers;
+    return result;
+}
+function _addElementPlacement(element, placements, silent) {
+    var keys = placements[element.placement];
+    if (!silent && keys.indexOf(element.key) !== -1) {
+        throw new TypeError("Duplicated element (" + element.key + ")");
+    }
+    keys.push(element.key);
+}
+function _decorateElement(element, placements) {
+    var extras = [];
+    var finishers = [];
+    for(var decorators = element.decorators, i = decorators.length - 1; i >= 0; i--){
+        var keys = placements[element.placement];
+        keys.splice(keys.indexOf(element.key), 1);
+        var elementObject = _fromElementDescriptor(element);
+        var elementFinisherExtras = _toElementFinisherExtras((0, decorators[i])(elementObject) || elementObject);
+        element = elementFinisherExtras.element;
+        _addElementPlacement(element, placements);
+        if (elementFinisherExtras.finisher) {
+            finishers.push(elementFinisherExtras.finisher);
+        }
+        var newExtras = elementFinisherExtras.extras;
+        if (newExtras) {
+            for(var j = 0; j < newExtras.length; j++){
+                _addElementPlacement(newExtras[j], placements);
+            }
+            extras.push.apply(extras, newExtras);
+        }
+    }
+    return {
+        element: element,
+        finishers: finishers,
+        extras: extras
+    };
+}
+function _decorateConstructor(elements, decorators) {
+    var finishers = [];
+    for(var i = decorators.length - 1; i >= 0; i--){
+        var obj = _fromClassDescriptor(elements);
+        var elementsAndFinisher = _toClassDescriptor((0, decorators[i])(obj) || obj);
+        if (elementsAndFinisher.finisher !== undefined) {
+            finishers.push(elementsAndFinisher.finisher);
+        }
+        if (elementsAndFinisher.elements !== undefined) {
+            elements = elementsAndFinisher.elements;
+            for(var j = 0; j < elements.length - 1; j++){
+                for(var k = j + 1; k < elements.length; k++){
+                    if (elements[j].key === elements[k].key && elements[j].placement === elements[k].placement) {
+                        throw new TypeError("Duplicated element (" + elements[j].key + ")");
+                    }
+                }
+            }
+        }
+    }
+    return {
+        elements: elements,
+        finishers: finishers
+    };
+}
+function _fromElementDescriptor(element) {
+    var obj = {
+        kind: element.kind,
+        key: element.key,
+        placement: element.placement,
+        descriptor: element.descriptor
+    };
+    var desc = {
+        value: "Descriptor",
+        configurable: true
+    };
+    Object.defineProperty(obj, Symbol.toStringTag, desc);
+    if (element.kind === "field") obj.initializer = element.initializer;
+    return obj;
+}
+function _toElementDescriptors(elementObjects) {
+    if (elementObjects === undefined) return;
+    return _toArray(elementObjects).map(function(elementObject) {
+        var element = _toElementDescriptor(elementObject);
+        _disallowProperty(elementObject, "finisher", "An element descriptor");
+        _disallowProperty(elementObject, "extras", "An element descriptor");
+        return element;
+    });
+}
+function _toElementDescriptor(elementObject) {
+    var kind = String(elementObject.kind);
+    if (kind !== "method" && kind !== "field") {
+        throw new TypeError("An element descriptor's .kind property must be either \"method\" or" + " \"field\", but a decorator created an element descriptor with" + " .kind \"" + kind + "\"");
+    }
+    var key = _toPropertyKey(elementObject.key);
+    var placement = String(elementObject.placement);
+    if (placement !== "static" && placement !== "prototype" && placement !== "own") {
+        throw new TypeError("An element descriptor's .placement property must be one of \"static\"," + " \"prototype\" or \"own\", but a decorator created an element descriptor" + " with .placement \"" + placement + "\"");
+    }
+    var descriptor = elementObject.descriptor;
+    _disallowProperty(elementObject, "elements", "An element descriptor");
+    var element = {
+        kind: kind,
+        key: key,
+        placement: placement,
+        descriptor: Object.assign({
+        }, descriptor)
+    };
+    if (kind !== "field") {
+        _disallowProperty(elementObject, "initializer", "A method descriptor");
+    } else {
+        _disallowProperty(descriptor, "get", "The property descriptor of a field descriptor");
+        _disallowProperty(descriptor, "set", "The property descriptor of a field descriptor");
+        _disallowProperty(descriptor, "value", "The property descriptor of a field descriptor");
+        element.initializer = elementObject.initializer;
+    }
+    return element;
+}
+function _toElementFinisherExtras(elementObject) {
+    var element = _toElementDescriptor(elementObject);
+    var finisher = _optionalCallableProperty(elementObject, "finisher");
+    var extras = _toElementDescriptors(elementObject.extras);
+    return {
+        element: element,
+        finisher: finisher,
+        extras: extras
+    };
+}
+function _fromClassDescriptor(elements) {
+    var obj = {
+        kind: "class",
+        elements: elements.map(_fromElementDescriptor)
+    };
+    var desc = {
+        value: "Descriptor",
+        configurable: true
+    };
+    Object.defineProperty(obj, Symbol.toStringTag, desc);
+    return obj;
+}
+function _toClassDescriptor(obj) {
+    var kind = String(obj.kind);
+    if (kind !== "class") {
+        throw new TypeError("A class descriptor's .kind property must be \"class\", but a decorator" + " created a class descriptor with .kind \"" + kind + "\"");
+    }
+    _disallowProperty(obj, "key", "A class descriptor");
+    _disallowProperty(obj, "placement", "A class descriptor");
+    _disallowProperty(obj, "descriptor", "A class descriptor");
+    _disallowProperty(obj, "initializer", "A class descriptor");
+    _disallowProperty(obj, "extras", "A class descriptor");
+    var finisher = _optionalCallableProperty(obj, "finisher");
+    var elements = _toElementDescriptors(obj.elements);
+    return {
+        elements: elements,
+        finisher: finisher
+    };
+}
+function _disallowProperty(obj, name, objectType) {
+    if (obj[name] !== undefined) {
+        throw new TypeError(objectType + " can't have a ." + name + " property.");
+    }
+}
+function _optionalCallableProperty(obj, name) {
+    var value = obj[name];
+    if (value !== undefined && typeof value !== "function") {
+        throw new TypeError("Expected '" + name + "' to be a function");
+    }
+    return value;
+}
+function _runClassFinishers(constructor, finishers) {
+    for(var i = 0; i < finishers.length; i++){
+        var newConstructor = (0, finishers[i])(constructor);
+        if (newConstructor !== undefined) {
+            if (typeof newConstructor !== "function") {
+                throw new TypeError("Finishers must return a constructor.");
+            }
+            constructor = newConstructor;
+        }
+    }
+    return constructor;
+}
+function _get(target, property, receiver) {
+    if (typeof Reflect !== "undefined" && Reflect.get) {
+        _get = Reflect.get;
+    } else {
+        _get = function _get(target, property, receiver) {
+            var base = _superPropBase(target, property);
+            if (!base) return;
+            var desc = Object.getOwnPropertyDescriptor(base, property);
+            if (desc.get) {
+                return desc.get.call(receiver);
+            }
+            return desc.value;
+        };
+    }
+    return _get(target, property, receiver || target);
+}
+function _getPrototypeOf(o) {
+    _getPrototypeOf = Object.setPrototypeOf ? Object.getPrototypeOf : function _getPrototypeOf(o) {
+        return o.__proto__ || Object.getPrototypeOf(o);
+    };
+    return _getPrototypeOf(o);
+}
+function _inherits(subClass, superClass) {
+    if (typeof superClass !== "function" && superClass !== null) {
+        throw new TypeError("Super expression must either be null or a function");
+    }
+    subClass.prototype = Object.create(superClass && superClass.prototype, {
+        constructor: {
+            value: subClass,
+            writable: true,
+            configurable: true
+        }
+    });
+    if (superClass) _setPrototypeOf(subClass, superClass);
+}
+function _iterableToArray(iter) {
+    if (Symbol.iterator in Object(iter) || Object.prototype.toString.call(iter) === "[object Arguments]") return Array.from(iter);
+}
+function _nonIterableRest() {
+    throw new TypeError("Invalid attempt to destructure non-iterable instance");
+}
+function _possibleConstructorReturn(self, call) {
+    if (call && (_typeof(call) === "object" || typeof call === "function")) {
+        return call;
+    }
+    return _assertThisInitialized(self);
+}
+function _setPrototypeOf(o, p) {
+    _setPrototypeOf = Object.setPrototypeOf || function _setPrototypeOf(o, p) {
+        o.__proto__ = p;
+        return o;
+    };
+    return _setPrototypeOf(o, p);
+}
+function _superPropBase(object, property) {
+    while(!Object.prototype.hasOwnProperty.call(object, property)){
+        object = _getPrototypeOf(object);
+        if (object === null) break;
+    }
+    return object;
+}
+function _toArray(arr) {
+    return _arrayWithHoles(arr) || _iterableToArray(arr) || _nonIterableRest();
+}
+function _toPrimitive(input, hint) {
+    if (_typeof(input) !== "object" || input === null) return input;
+    var prim = input[Symbol.toPrimitive];
+    if (prim !== undefined) {
+        var res = prim.call(input, hint || "default");
+        if (_typeof(res) !== "object") return res;
+        throw new TypeError("@@toPrimitive must return a primitive value.");
+    }
+    return (hint === "string" ? String : Number)(input);
+}
+function _toPropertyKey(arg) {
+    var key = _toPrimitive(arg, "string");
+    return _typeof(key) === "symbol" ? key : String(key);
+}
+var _typeof = function(obj) {
+    return obj && typeof Symbol !== "undefined" && obj.constructor === Symbol ? "symbol" : typeof obj;
+};
+var SomeClass = _decorate([], function(_initialize) {
+    var SomeClass1 = function SomeClass1() {
+        "use strict";
+        _classCallCheck(this, SomeClass1);
+        _initialize(this);
+    };
+    return {
+        F: SomeClass1,
+        d: [
+            {
+                kind: "method",
+                decorators: [
+                    dec
+                ],
+                key: "someMethod",
+                value: function someMethod() {
+                }
+            }
+        ]
+    };
+});
+var OtherClass = _decorate([], function(_initialize, _SomeClass) {
+    var OtherClass1 = /*#__PURE__*/ function(_SomeClass1) {
+        "use strict";
+        _inherits(OtherClass1, _SomeClass1);
+        function OtherClass1() {
+            _classCallCheck(this, OtherClass1);
+            var _this;
+            _this = _possibleConstructorReturn(this, _getPrototypeOf(OtherClass1).apply(this, arguments));
+            _initialize(_assertThisInitialized(_this));
+            return _this;
+        }
+        return OtherClass1;
+    }(_SomeClass);
+    return {
+        F: OtherClass1,
+        d: [
+            {
+                kind: "method",
+                decorators: [
+                    dec
+                ],
+                key: "anotherMethod",
+                value: function anotherMethod() {
+                    _get(_getPrototypeOf(OtherClass1.prototype), "someMethod", this).call(this);
+                }
+            }
+        ]
+    };
+}, SomeClass);

wasm/Cargo.toml

@@ -6,7 +6,7 @@ license = "Apache-2.0/MIT"
 name = "wasm"
 publish = false
 repository = "https://github.com/swc-project/swc.git"
-version = "1.2.59"
+version = "1.2.60"
 
 [lib]
 crate-type = ["cdylib"]