fix(es/decorators): Fix syntax context of decorated classes (#4905)

crates/swc/tests/fixture/issues-1xxx/1869/decorator/output/index.ts

@@ -1,9 +1,9 @@
 import _class_call_check from "@swc/helpers/lib/_class_call_check.js";
 import _ts_decorate from "@swc/helpers/lib/_ts_decorate.js";
 var _TestClass;
-var TestClass = (_TestClass = function TestClass() {
+var TestClass = (_TestClass = function TestClass1() {
     "use strict";
-    _class_call_check(this, TestClass);
+    _class_call_check(this, TestClass1);
 }, _TestClass.Something = "hello", _TestClass.SomeProperties = {
     firstProp: _TestClass.Something
 }, _TestClass);

crates/swc/tests/fixture/issues-4xxx/4899/input/.swcrc

@@ -0,0 +1,22 @@
+{
+    "$schema": "http://json.schemastore.org/swcrc",
+    "exclude": "\\.js$",
+    "jsc": {
+        "parser": {
+            "syntax": "typescript",
+            "tsx": false,
+            "decorators": true
+        },
+        "target": "es2020",
+        "loose": false,
+        "minify": {
+            "compress": false,
+            "mangle": false
+        }
+    },
+    "module": {
+        "type": "amd",
+        "noInterop": true
+    },
+    "minify": false
+}

crates/swc/tests/fixture/issues-4xxx/4899/input/index.ts

@@ -0,0 +1,23 @@
+function es5ClassCompat(target: Function): any {
+    ///@ts-expect-error
+    function _() {
+        return Reflect.construct(target, arguments, this.constructor);
+    }
+    Object.defineProperty(
+        _,
+        "name",
+        Object.getOwnPropertyDescriptor(target, "name")!
+    );
+    Object.setPrototypeOf(_, target);
+    Object.setPrototypeOf(_.prototype, target.prototype);
+    return _;
+}
+
+@es5ClassCompat
+class Foo {
+    static create() {
+        return new Foo();
+    }
+
+    constructor() {}
+}

crates/swc/tests/fixture/issues-4xxx/4899/output/index.ts

@@ -0,0 +1,24 @@
+define([
+    "require",
+    "@swc/helpers/lib/_ts_decorate.js"
+], function(require, _ts_decorate) {
+    "use strict";
+    function es5ClassCompat(target) {
+        function _() {
+            return Reflect.construct(target, arguments, this.constructor);
+        }
+        Object.defineProperty(_, "name", Object.getOwnPropertyDescriptor(target, "name"));
+        Object.setPrototypeOf(_, target);
+        Object.setPrototypeOf(_.prototype, target.prototype);
+        return _;
+    }
+    let Foo = class Foo1 {
+        static create() {
+            return new Foo();
+        }
+        constructor(){}
+    };
+    Foo = _ts_decorate([
+        es5ClassCompat
+    ], Foo);
+});

crates/swc_ecma_transforms/tests/fixture/legacy-only/issues/1869/1/output.ts

@@ -1,7 +1,7 @@
-let TestClass = class TestClass {
+let TestClass = class TestClass1 {
     static Something = "hello";
     static SomeProperties = {
-        firstProp: TestClass.Something
+        firstProp: TestClass1.Something
     };
 };
 TestClass = __decorate([

crates/swc_ecma_transforms_proposal/src/decorators/legacy/mod.rs

@@ -4,7 +4,7 @@ use swc_ecma_ast::*;
 use swc_ecma_transforms_base::helper;
 use swc_ecma_utils::{
     constructor::inject_after_super, default_constructor, private_ident, prop_name_to_expr_value,
-    quote_ident, undefined, ExprFactory, StmtLike,
+    quote_ident, replace_ident, undefined, ExprFactory, StmtLike,
 };
 use swc_ecma_visit::{Visit, VisitMut, VisitMutWith, VisitWith};
 
@@ -358,11 +358,26 @@ impl VisitMut for TscDecorator {
                 decl.visit_mut_with(self);
 
                 if convert_to_let {
+                    let inner_ident = private_ident!(decl.ident.sym.clone());
+
+                    decl.class.body.iter_mut().for_each(|m| match m {
+                        ClassMember::PrivateProp(PrivateProp {
+                            is_static: true, ..
+                        })
+                        | ClassMember::StaticBlock(..)
+                        | ClassMember::ClassProp(ClassProp {
+                            is_static: true, ..
+                        }) => {
+                            replace_ident(m, decl.ident.to_id(), &inner_ident);
+                        }
+                        _ => {}
+                    });
+
                     let d = VarDeclarator {
                         span: DUMMY_SP,
                         name: decl.ident.clone().into(),
                         init: Some(Box::new(Expr::Class(ClassExpr {
-                            ident: Some(decl.ident.clone()),
+                            ident: Some(inner_ident),
                             class: decl.class.take(),
                         }))),
                         definite: Default::default(),

crates/swc_ecma_utils/src/lib.rs

@@ -2292,6 +2292,27 @@ impl VisitMut for IdentReplacer<'_> {
 
     visit_mut_obj_and_computed!();
 
+    fn visit_mut_prop(&mut self, node: &mut Prop) {
+        match node {
+            Prop::Shorthand(i) => {
+                let cloned = i.clone();
+                i.visit_mut_with(self);
+                if i.sym != cloned.sym || i.span.ctxt != cloned.span.ctxt {
+                    *node = Prop::KeyValue(KeyValueProp {
+                        key: PropName::Ident(Ident::new(
+                            cloned.sym,
+                            cloned.span.with_ctxt(SyntaxContext::empty()),
+                        )),
+                        value: Box::new(Expr::Ident(i.clone())),
+                    });
+                }
+            }
+            _ => {
+                node.visit_mut_children_with(self);
+            }
+        }
+    }
+
     fn visit_mut_ident(&mut self, node: &mut Ident) {
         if node.sym == self.from.0 && node.span.ctxt == self.from.1 {
             *node = self.to.clone();