fix(es/compat): Handle label block in constructor (#9528)

**Related issue:**
- Closes https://github.com/swc-project/swc/issues/9527

.changeset/popular-fireants-hang.md

@@ -0,0 +1,7 @@
+---
+swc_ecma_compat_es2015: patch
+swc_ecma_transforms_compat: patch
+swc_core: patch
+---
+
+fix(es/compat): Handle label block in constructor

crates/swc/tests/exec/issues-9xxx/9527/.swcrc

@@ -0,0 +1,10 @@
+{
+  "jsc": {
+    "parser": {
+      "syntax": "ecmascript"
+    },
+    "externalHelpers": false,
+    "target": "es5"
+  },
+  "isModule": true
+}

crates/swc/tests/exec/issues-9xxx/9527/1/exec.js

@@ -0,0 +1,50 @@
+class Base { };
+
+expect(() => new class extends Base {
+    constructor() {
+        x: { break x; super(); }
+    }
+}).toThrow();
+
+expect(() => new class extends Base {
+    constructor() {
+        try { } catch { super(); }
+    }
+}).toThrow();
+
+expect(() => new class extends Base {
+    constructor() {
+        try { throw 0; super(); } catch { }
+    }
+}).toThrow();
+
+expect(() => new class extends Base {
+    constructor() {
+        true || super();
+    }
+}).toThrow();
+
+expect(() => new class extends Base {
+    constructor() {
+        ({}) ?? super();
+    }
+}).toThrow();
+
+expect(() => new class extends Base {
+    constructor() {
+        false && super();
+    }
+}).toThrow();
+
+expect(() => new class extends Base {
+    constructor() {
+        null?.(super());
+    }
+}).toThrow();
+
+
+expect(() => new class extends Base {
+    constructor() {
+        null?.[super()];
+    }
+}).toThrow();

crates/swc/tests/fixture/issues-9xxx/9527/input/.swcrc

@@ -0,0 +1,10 @@
+{
+  "jsc": {
+    "parser": {
+      "syntax": "ecmascript"
+    },
+    "externalHelpers": false,
+    "target": "es5"
+  },
+  "isModule": true
+}

crates/swc/tests/fixture/issues-9xxx/9527/input/2.js

@@ -0,0 +1,17 @@
+class Bar { }
+class Foo extends Bar {
+    constructor() {
+        switch (0) {
+            case 0:
+                break;
+            default:
+                super();
+        }
+    }
+}
+
+try {
+    new Foo();
+} catch {
+    console.log("catched");
+}

crates/swc/tests/fixture/issues-9xxx/9527/input/exec.js

@@ -0,0 +1,50 @@
+class Base { };
+
+expect(() => new class extends Base {
+    constructor() {
+        x: { break x; super(); }
+    }
+}).toThrow();
+
+expect(() => new class extends Base {
+    constructor() {
+        try { } catch { super(); }
+    }
+}).toThrow();
+
+expect(() => new class extends Base {
+    constructor() {
+        try { throw 0; super(); } catch { }
+    }
+}).toThrow();
+
+expect(() => new class extends Base {
+    constructor() {
+        true || super();
+    }
+}).toThrow();
+
+expect(() => new class extends Base {
+    constructor() {
+        ({}) ?? super();
+    }
+}).toThrow();
+
+expect(() => new class extends Base {
+    constructor() {
+        false && super();
+    }
+}).toThrow();
+
+expect(() => new class extends Base {
+    constructor() {
+        null?.(super());
+    }
+}).toThrow();
+
+
+expect(() => new class extends Base {
+    constructor() {
+        null?.[super()];
+    }
+}).toThrow();

crates/swc/tests/fixture/issues-9xxx/9527/input/index.js

@@ -0,0 +1,15 @@
+class Bar { }
+class Foo extends Bar {
+    constructor() {
+        x: {
+            break x;
+            super();
+        }
+    }
+}
+
+try {
+    new Foo();
+} catch {
+    console.log("catched");
+}

crates/swc/tests/fixture/issues-9xxx/9527/input/test.js

@@ -0,0 +1,25 @@
+class Base { };
+
+new class extends Base {
+    constructor() {
+        super() || null;
+    }
+}
+
+new class extends Base {
+    constructor() {
+        super()?.();
+    }
+}
+
+new class extends Base {
+    constructor() {
+        super()?.[null];
+    }
+}
+
+new class extends Base {
+    constructor() {
+        1 + super();
+    }
+}

crates/swc/tests/fixture/issues-9xxx/9527/output/2.js

@@ -0,0 +1,29 @@
+var _assert_this_initialized = require("@swc/helpers/_/_assert_this_initialized");
+var _call_super = require("@swc/helpers/_/_call_super");
+var _class_call_check = require("@swc/helpers/_/_class_call_check");
+var _inherits = require("@swc/helpers/_/_inherits");
+var Bar = function Bar() {
+    "use strict";
+    _class_call_check._(this, Bar);
+};
+var Foo = /*#__PURE__*/ function(Bar) {
+    "use strict";
+    _inherits._(Foo, Bar);
+    function Foo() {
+        _class_call_check._(this, Foo);
+        var _this;
+        switch(0){
+            case 0:
+                break;
+            default:
+                _this = _call_super._(this, Foo);
+        }
+        return _assert_this_initialized._(_this);
+    }
+    return Foo;
+}(Bar);
+try {
+    new Foo();
+} catch (e) {
+    console.log("catched");
+}

crates/swc/tests/fixture/issues-9xxx/9527/output/exec.js

@@ -0,0 +1,124 @@
+var _assert_this_initialized = require("@swc/helpers/_/_assert_this_initialized");
+var _call_super = require("@swc/helpers/_/_call_super");
+var _class_call_check = require("@swc/helpers/_/_class_call_check");
+var _inherits = require("@swc/helpers/_/_inherits");
+var Base = function Base() {
+    "use strict";
+    _class_call_check._(this, Base);
+};
+;
+expect(function() {
+    return new /*#__PURE__*/ (function(Base) {
+        "use strict";
+        _inherits._(_class, Base);
+        function _class() {
+            _class_call_check._(this, _class);
+            var _this;
+            x: {
+                break x;
+                _this = _call_super._(this, _class);
+            }
+            return _assert_this_initialized._(_this);
+        }
+        return _class;
+    }(Base));
+}).toThrow();
+expect(function() {
+    return new /*#__PURE__*/ (function(Base) {
+        "use strict";
+        _inherits._(_class, Base);
+        function _class() {
+            _class_call_check._(this, _class);
+            var _this;
+            try {} catch (e) {
+                _this = _call_super._(this, _class);
+            }
+            return _assert_this_initialized._(_this);
+        }
+        return _class;
+    }(Base));
+}).toThrow();
+expect(function() {
+    return new /*#__PURE__*/ (function(Base) {
+        "use strict";
+        _inherits._(_class, Base);
+        function _class() {
+            _class_call_check._(this, _class);
+            var _this;
+            try {
+                throw 0;
+                _this = _call_super._(this, _class);
+            } catch (e) {}
+            return _assert_this_initialized._(_this);
+        }
+        return _class;
+    }(Base));
+}).toThrow();
+expect(function() {
+    return new /*#__PURE__*/ (function(Base) {
+        "use strict";
+        _inherits._(_class, Base);
+        function _class() {
+            _class_call_check._(this, _class);
+            var _this;
+            true || (_this = _call_super._(this, _class));
+            return _assert_this_initialized._(_this);
+        }
+        return _class;
+    }(Base));
+}).toThrow();
+expect(function() {
+    return new /*#__PURE__*/ (function(Base) {
+        "use strict";
+        _inherits._(_class, Base);
+        function _class() {
+            _class_call_check._(this, _class);
+            var _this;
+            var _ref;
+            (_ref = {}) !== null && _ref !== void 0 ? _ref : _this = _call_super._(this, _class);
+            return _assert_this_initialized._(_this);
+        }
+        return _class;
+    }(Base));
+}).toThrow();
+expect(function() {
+    return new /*#__PURE__*/ (function(Base) {
+        "use strict";
+        _inherits._(_class, Base);
+        function _class() {
+            _class_call_check._(this, _class);
+            var _this;
+            false && (_this = _call_super._(this, _class));
+            return _assert_this_initialized._(_this);
+        }
+        return _class;
+    }(Base));
+}).toThrow();
+expect(function() {
+    return new /*#__PURE__*/ (function(Base) {
+        "use strict";
+        _inherits._(_class, Base);
+        function _class() {
+            _class_call_check._(this, _class);
+            var _this;
+            var _this1;
+            (_this1 = null) === null || _this1 === void 0 ? void 0 : _this1(_this = _call_super._(this, _class));
+            return _assert_this_initialized._(_this);
+        }
+        return _class;
+    }(Base));
+}).toThrow();
+expect(function() {
+    return new /*#__PURE__*/ (function(Base) {
+        "use strict";
+        _inherits._(_class, Base);
+        function _class() {
+            _class_call_check._(this, _class);
+            var _this;
+            var _this1;
+            (_this1 = null) === null || _this1 === void 0 ? void 0 : _this1[_this = _call_super._(this, _class)];
+            return _assert_this_initialized._(_this);
+        }
+        return _class;
+    }(Base));
+}).toThrow();

crates/swc/tests/fixture/issues-9xxx/9527/output/index.js

@@ -0,0 +1,27 @@
+var _assert_this_initialized = require("@swc/helpers/_/_assert_this_initialized");
+var _call_super = require("@swc/helpers/_/_call_super");
+var _class_call_check = require("@swc/helpers/_/_class_call_check");
+var _inherits = require("@swc/helpers/_/_inherits");
+var Bar = function Bar() {
+    "use strict";
+    _class_call_check._(this, Bar);
+};
+var Foo = /*#__PURE__*/ function(Bar) {
+    "use strict";
+    _inherits._(Foo, Bar);
+    function Foo() {
+        _class_call_check._(this, Foo);
+        var _this;
+        x: {
+            break x;
+            _this = _call_super._(this, Foo);
+        }
+        return _assert_this_initialized._(_this);
+    }
+    return Foo;
+}(Bar);
+try {
+    new Foo();
+} catch (e) {
+    console.log("catched");
+}

crates/swc/tests/fixture/issues-9xxx/9527/output/test.js

@@ -0,0 +1,54 @@
+var _call_super = require("@swc/helpers/_/_call_super");
+var _class_call_check = require("@swc/helpers/_/_class_call_check");
+var _inherits = require("@swc/helpers/_/_inherits");
+var Base = function Base() {
+    "use strict";
+    _class_call_check._(this, Base);
+};
+;
+new /*#__PURE__*/ (function(Base) {
+    "use strict";
+    _inherits._(_class, Base);
+    function _class() {
+        _class_call_check._(this, _class);
+        var _this;
+        (_this = _call_super._(this, _class)) || null;
+        return _this;
+    }
+    return _class;
+}(Base));
+new /*#__PURE__*/ (function(Base) {
+    "use strict";
+    _inherits._(_class, Base);
+    function _class() {
+        _class_call_check._(this, _class);
+        var _this;
+        var _this1;
+        (_this1 = _this = _call_super._(this, _class)) === null || _this1 === void 0 ? void 0 : _this1();
+        return _this;
+    }
+    return _class;
+}(Base));
+new /*#__PURE__*/ (function(Base) {
+    "use strict";
+    _inherits._(_class, Base);
+    function _class() {
+        _class_call_check._(this, _class);
+        var _this;
+        var _this1;
+        (_this1 = _this = _call_super._(this, _class)) === null || _this1 === void 0 ? void 0 : _this1[null];
+        return _this;
+    }
+    return _class;
+}(Base));
+new /*#__PURE__*/ (function(Base) {
+    "use strict";
+    _inherits._(_class, Base);
+    function _class() {
+        _class_call_check._(this, _class);
+        var _this;
+        1 + (_this = _call_super._(this, _class));
+        return _this;
+    }
+    return _class;
+}(Base));

crates/swc/tests/tsc-references/constructorFunctionTypeIsAssignableToBaseType2.1.normal.js

@@ -29,7 +29,6 @@ var Derived2 = /*#__PURE__*/ function(Base) {
             x
         ]);
         return _possible_constructor_return(_this, 1);
-        return _this;
     }
     return Derived2;
 }(Base);

crates/swc/tests/tsc-references/derivedClassConstructorWithoutSuperCall.1.normal.js

@@ -1,9 +1,9 @@
 //// [derivedClassConstructorWithoutSuperCall.ts]
 // derived class constructors must contain a super call
+import { _ as _assert_this_initialized } from "@swc/helpers/_/_assert_this_initialized";
 import { _ as _call_super } from "@swc/helpers/_/_call_super";
 import { _ as _class_call_check } from "@swc/helpers/_/_class_call_check";
 import { _ as _inherits } from "@swc/helpers/_/_inherits";
-import { _ as _possible_constructor_return } from "@swc/helpers/_/_possible_constructor_return";
 var Base = function Base() {
     "use strict";
     _class_call_check(this, Base);
@@ -13,7 +13,7 @@ var Derived = /*#__PURE__*/ function(Base) {
     _inherits(Derived, Base);
     function Derived() {
         _class_call_check(this, Derived);
-        return _possible_constructor_return(void 0);
+        return _assert_this_initialized(void 0);
     }
     return Derived;
 }(Base);
@@ -31,7 +31,7 @@ var Derived2 = /*#__PURE__*/ function(Base2) {
         var r2 = function() {
             return _this1 = _call_super(_this, Derived2);
         }; // error for misplaced super call (nested function)
-        return _possible_constructor_return(_this1);
+        return _assert_this_initialized(_this1);
     }
     return Derived2;
 }(Base2);
@@ -44,7 +44,7 @@ var Derived3 = /*#__PURE__*/ function(Base2) {
             super();
         } // error
         ;
-        return _possible_constructor_return(void 0);
+        return _assert_this_initialized(void 0);
     }
     return Derived3;
 }(Base2);

crates/swc/tests/tsc-references/derivedClassConstructorWithoutSuperCall.2.minified.js

@@ -1,5 +1,5 @@
 //// [derivedClassConstructorWithoutSuperCall.ts]
+import { _ as _assert_this_initialized } from "@swc/helpers/_/_assert_this_initialized";
 import { _ as _call_super } from "@swc/helpers/_/_call_super";
 import { _ as _class_call_check } from "@swc/helpers/_/_class_call_check";
 import { _ as _inherits } from "@swc/helpers/_/_inherits";
-import { _ as _possible_constructor_return } from "@swc/helpers/_/_possible_constructor_return";

crates/swc/tests/tsc-references/jsDeclarationsClasses.1.normal.js

@@ -4,7 +4,6 @@ import { _ as _call_super } from "@swc/helpers/_/_call_super";
 import { _ as _class_call_check } from "@swc/helpers/_/_class_call_check";
 import { _ as _create_class } from "@swc/helpers/_/_create_class";
 import { _ as _inherits } from "@swc/helpers/_/_inherits";
-import { _ as _possible_constructor_return } from "@swc/helpers/_/_possible_constructor_return";
 export var A = function A() {
     "use strict";
     _class_call_check(this, A);
@@ -155,7 +154,7 @@ export var M = /*#__PURE__*/ function(_superClass) {
         _class_call_check(this, M);
         var _this;
         _assert_this_initialized(_this).prop = 12;
-        return _possible_constructor_return(_this);
+        return _assert_this_initialized(_this);
     }
     return M;
 }(null);

crates/swc/tests/tsc-references/jsDeclarationsClasses.2.minified.js

@@ -4,7 +4,6 @@ import { _ as _call_super } from "@swc/helpers/_/_call_super";
 import { _ as _class_call_check } from "@swc/helpers/_/_class_call_check";
 import { _ as _create_class } from "@swc/helpers/_/_create_class";
 import { _ as _inherits } from "@swc/helpers/_/_inherits";
-import { _ as _possible_constructor_return } from "@swc/helpers/_/_possible_constructor_return";
 export var A = function A() {
     _class_call_check(this, A);
 };
@@ -101,7 +100,7 @@ export var L = /*#__PURE__*/ function(K) {
 export var M = /*#__PURE__*/ function(_superClass) {
     function M() {
         var _this;
-        return _class_call_check(this, M), _assert_this_initialized(_this).prop = 12, _possible_constructor_return(_this);
+        return _class_call_check(this, M), _assert_this_initialized(_this).prop = 12, _assert_this_initialized(_this);
     }
     return _inherits(M, null), M;
 }(0);

crates/swc/tests/tsc-references/superCallBeforeThisAccessing5.1.normal.js

@@ -2,7 +2,6 @@
 import { _ as _assert_this_initialized } from "@swc/helpers/_/_assert_this_initialized";
 import { _ as _class_call_check } from "@swc/helpers/_/_class_call_check";
 import { _ as _inherits } from "@swc/helpers/_/_inherits";
-import { _ as _possible_constructor_return } from "@swc/helpers/_/_possible_constructor_return";
 var D = /*#__PURE__*/ function(_superClass) {
     "use strict";
     _inherits(D, _superClass);
@@ -10,7 +9,7 @@ var D = /*#__PURE__*/ function(_superClass) {
         _class_call_check(this, D);
         var _this;
         _assert_this_initialized(_this)._t; // No error
-        return _possible_constructor_return(_this);
+        return _assert_this_initialized(_this);
     }
     return D;
 }(null);

crates/swc/tests/tsc-references/superCallBeforeThisAccessing5.2.minified.js

@@ -2,4 +2,3 @@
 import { _ as _assert_this_initialized } from "@swc/helpers/_/_assert_this_initialized";
 import { _ as _class_call_check } from "@swc/helpers/_/_class_call_check";
 import { _ as _inherits } from "@swc/helpers/_/_inherits";
-import { _ as _possible_constructor_return } from "@swc/helpers/_/_possible_constructor_return";

crates/swc/tests/tsc-references/usingDeclarations.1(target=es5).1.normal.js

@@ -1,4 +1,5 @@
 //// [usingDeclarations.1.ts]
+import { _ as _assert_this_initialized } from "@swc/helpers/_/_assert_this_initialized";
 import { _ as _async_to_generator } from "@swc/helpers/_/_async_to_generator";
 import { _ as _await_async_generator } from "@swc/helpers/_/_await_async_generator";
 import { _ as _call_super } from "@swc/helpers/_/_call_super";
@@ -6,7 +7,6 @@ import { _ as _class_call_check } from "@swc/helpers/_/_class_call_check";
 import { _ as _create_class } from "@swc/helpers/_/_create_class";
 import { _ as _define_property } from "@swc/helpers/_/_define_property";
 import { _ as _inherits } from "@swc/helpers/_/_inherits";
-import { _ as _possible_constructor_return } from "@swc/helpers/_/_possible_constructor_return";
 import { _ as _wrap_async_generator } from "@swc/helpers/_/_wrap_async_generator";
 import { _ as _ts_generator } from "@swc/helpers/_/_ts_generator";
 import { _ as _using_ctx } from "@swc/helpers/_/_using_ctx";
@@ -396,7 +396,7 @@ try {
             } finally{
                 _usingCtx.d();
             }
-            return _possible_constructor_return(_this);
+            return _assert_this_initialized(_this);
         }
         return C2;
     }(C1);
@@ -415,7 +415,7 @@ try {
             } finally{
                 _usingCtx.d();
             }
-            return _possible_constructor_return(_this);
+            return _assert_this_initialized(_this);
         }
         return C3;
     }(C1);

crates/swc/tests/tsc-references/usingDeclarations.1(target=es5).2.minified.js

@@ -1,4 +1,5 @@
 //// [usingDeclarations.1.ts]
+import { _ as _assert_this_initialized } from "@swc/helpers/_/_assert_this_initialized";
 import { _ as _async_to_generator } from "@swc/helpers/_/_async_to_generator";
 import { _ as _await_async_generator } from "@swc/helpers/_/_await_async_generator";
 import { _ as _call_super } from "@swc/helpers/_/_call_super";
@@ -6,7 +7,6 @@ import { _ as _class_call_check } from "@swc/helpers/_/_class_call_check";
 import { _ as _create_class } from "@swc/helpers/_/_create_class";
 import { _ as _define_property } from "@swc/helpers/_/_define_property";
 import { _ as _inherits } from "@swc/helpers/_/_inherits";
-import { _ as _possible_constructor_return } from "@swc/helpers/_/_possible_constructor_return";
 import { _ as _wrap_async_generator } from "@swc/helpers/_/_wrap_async_generator";
 import { _ as _ts_generator } from "@swc/helpers/_/_ts_generator";
 import { _ as _using_ctx } from "@swc/helpers/_/_using_ctx";

crates/swc/tests/tsc-references/usingDeclarations.11.1.normal.js

@@ -1,8 +1,8 @@
 //// [usingDeclarations.11.ts]
+import { _ as _assert_this_initialized } from "@swc/helpers/_/_assert_this_initialized";
 import { _ as _call_super } from "@swc/helpers/_/_call_super";
 import { _ as _class_call_check } from "@swc/helpers/_/_class_call_check";
 import { _ as _inherits } from "@swc/helpers/_/_inherits";
-import { _ as _possible_constructor_return } from "@swc/helpers/_/_possible_constructor_return";
 import { _ as _using_ctx } from "@swc/helpers/_/_using_ctx";
 var A = function A() {
     "use strict";
@@ -23,7 +23,7 @@ var C1 = /*#__PURE__*/ function(A) {
         } finally{
             _usingCtx.d();
         }
-        return _possible_constructor_return(_this);
+        return _assert_this_initialized(_this);
     }
     return C1;
 }(A);
@@ -42,7 +42,7 @@ var C2 = /*#__PURE__*/ function(A) {
         } finally{
             _usingCtx.d();
         }
-        return _possible_constructor_return(_this);
+        return _assert_this_initialized(_this);
     }
     return C2;
 }(A);
@@ -61,7 +61,7 @@ var C3 = /*#__PURE__*/ function(A) {
         } finally{
             _usingCtx.d();
         }
-        return _possible_constructor_return(_this);
+        return _assert_this_initialized(_this);
     }
     return C3;
 }(A);
@@ -80,7 +80,7 @@ var C4 = /*#__PURE__*/ function(A) {
         } finally{
             _usingCtx.d();
         }
-        return _possible_constructor_return(_this);
+        return _assert_this_initialized(_this);
     }
     return C4;
 }(A);
@@ -99,7 +99,7 @@ var C5 = /*#__PURE__*/ function(A) {
         } finally{
             _usingCtx.d();
         }
-        return _possible_constructor_return(_this);
+        return _assert_this_initialized(_this);
     }
     return C5;
 }(A);

crates/swc/tests/tsc-references/usingDeclarations.11.2.minified.js

@@ -1,6 +1,6 @@
 //// [usingDeclarations.11.ts]
+import { _ as _assert_this_initialized } from "@swc/helpers/_/_assert_this_initialized";
 import { _ as _call_super } from "@swc/helpers/_/_call_super";
 import { _ as _class_call_check } from "@swc/helpers/_/_class_call_check";
 import { _ as _inherits } from "@swc/helpers/_/_inherits";
-import { _ as _possible_constructor_return } from "@swc/helpers/_/_possible_constructor_return";
 import { _ as _using_ctx } from "@swc/helpers/_/_using_ctx";

crates/swc_ecma_compat_es2015/src/classes/constructor.rs

@@ -58,6 +58,7 @@ pub(super) fn fold_constructor(
     let mut body = constructor.body.take().unwrap();
     if let Some(class_super_name) = class_super_name {
         let is_last_super = (&*body.stmts).is_super_last_call();
+        let is_last_return = body.stmts.last().map_or(false, Stmt::is_return_stmt);
 
         let mut constructor_folder = ConstructorFolder {
             class_key_init: vec![],
@@ -134,7 +135,7 @@ pub(super) fn fold_constructor(
             stmts.push(var.into());
         }
 
-        if !is_last_super {
+        if !is_last_super && !is_last_return {
             let this = if constructor_folder.super_found {
                 Expr::Ident(constructor_folder.this.unwrap())
             } else {
@@ -142,7 +143,7 @@ pub(super) fn fold_constructor(
                     .this
                     .map_or_else(|| Expr::undefined(DUMMY_SP).as_arg(), |this| this.as_arg());
 
-                helper_expr!(possible_constructor_return).as_call(DUMMY_SP, vec![this])
+                helper_expr!(assert_this_initialized).as_call(DUMMY_SP, vec![this])
             };
 
             let return_this = ReturnStmt {
@@ -303,6 +304,13 @@ impl VisitMut for ConstructorFolder {
         self.super_found = super_found;
     }
 
+    fn visit_mut_switch_stmt(&mut self, node: &mut SwitchStmt) {
+        node.discriminant.visit_mut_with(self);
+        let super_found = self.super_found;
+        node.cases.visit_mut_with(self);
+        self.super_found = super_found;
+    }
+
     fn visit_mut_try_stmt(&mut self, node: &mut TryStmt) {
         let super_found = self.super_found;
         node.block.visit_mut_with(self);
@@ -311,6 +319,16 @@ impl VisitMut for ConstructorFolder {
         node.finalizer.visit_mut_with(self);
     }
 
+    fn visit_mut_labeled_stmt(&mut self, node: &mut LabeledStmt) {
+        if node.body.is_block() {
+            let super_found = self.super_found;
+            node.body.visit_mut_with(self);
+            self.super_found = super_found;
+        } else {
+            node.body.visit_mut_with(self);
+        }
+    }
+
     fn visit_mut_bin_expr(&mut self, node: &mut BinExpr) {
         match node.op {
             op!("&&") | op!("||") => {

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2015_classes.rs/constant_super_update.js

@@ -8,7 +8,7 @@ let A = /*#__PURE__*/ function(B) {
         _update(A.prototype, "bar", _this, true)._ += 123;
         _update(A.prototype, baz, _this, true)._--;
         _update(A.prototype, quz, _this, true)._ -= 456;
-        return _possible_constructor_return(_this);
+        return _assert_this_initialized(_this);
     }
     return A;
 }(B);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2015_classes.rs/constructor_super_update.js

@@ -8,7 +8,7 @@ let A = /*#__PURE__*/ function(B) {
         _update((_assert_this_initialized(_this), _get_prototype_of(A.prototype)), "bar", _this, true)._ += 123;
         _update((_assert_this_initialized(_this), _get_prototype_of(A.prototype)), baz, _this, true)._--;
         _update((_assert_this_initialized(_this), _get_prototype_of(A.prototype)), quz, _this, true)._ -= 456;
-        return _possible_constructor_return(_this);
+        return _assert_this_initialized(_this);
     }
     return A;
 }(B);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2015_classes.rs/duplicate_ident.js

@@ -5,7 +5,7 @@ let Foo = /*#__PURE__*/ function(Bar1) {
         _class_call_check(this, Foo);
         var Foo1 = 123;
         console.log(Foo1);
-        return _possible_constructor_return(void 0);
+        return _assert_this_initialized(void 0);
     }
     return Foo;
 }(Bar);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2015_classes.rs/nested_this_in_key.js

@@ -22,7 +22,6 @@ let Outer = /*#__PURE__*/ function(B) {
             return this;
         }
         return _possible_constructor_return(_this, new Inner());
-        return _possible_constructor_return(_this);
     }
     return Outer;
 }(B);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2015_classes.rs/no_class_call_super.js

@@ -10,7 +10,7 @@ let A = /*#__PURE__*/ function(B) {
             track
         ]);
         else _this = _call_super(this, A);
-        return _possible_constructor_return(_this);
+        return _assert_this_initialized(_this);
     }
     return A;
 }(B);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2015_classes.rs/spec_derived_constructor_must_call_super.js

@@ -3,7 +3,7 @@ var Foo = /*#__PURE__*/ function(Bar1) {
     _inherits(Foo, Bar1);
     function Foo() {
         _class_call_check(this, Foo);
-        return _possible_constructor_return(void 0);
+        return _assert_this_initialized(void 0);
     }
     return Foo;
 }(Bar);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2015_classes.rs/spec_derived_constructor_must_call_super_2.js

@@ -5,7 +5,7 @@ var Foo = /*#__PURE__*/ function(Bar1) {
         _class_call_check(this, Foo);
         var _this;
         if (eval("false")) _this = _call_super(this, Foo);
-        return _possible_constructor_return(_this);
+        return _assert_this_initialized(_this);
     }
     return Foo;
 }(Bar);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2015_classes.rs/spec_derived_constructor_must_call_super_3.js

@@ -6,7 +6,7 @@ var Foo = /*#__PURE__*/ function(Bar1) {
         var _this;
         var fn = ()=>_this = _call_super(this, Foo);
         fn();
-        return _possible_constructor_return(_this);
+        return _assert_this_initialized(_this);
     }
     return Foo;
 }(Bar);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2015_classes.rs/spec_derived_constructor_must_call_super_4.js

@@ -5,7 +5,7 @@ var Foo = /*#__PURE__*/ function(Bar1) {
         _class_call_check(this, Foo);
         var _this;
         var fn = ()=>_this = _call_super(this, Foo);
-        return _possible_constructor_return(_this);
+        return _assert_this_initialized(_this);
     }
     return Foo;
 }(Bar);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2015_classes.rs/spec_derived_constructor_no_super_return_falsey.js

@@ -5,7 +5,6 @@ var Child = /*#__PURE__*/ function(Base1) {
         _class_call_check(this, Child);
         var _this;
         return _possible_constructor_return(_this, false);
-        return _possible_constructor_return(_this);
     }
     return Child;
 }(Base);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2015_classes.rs/spec_derived_constructor_no_super_return_object.js

@@ -5,7 +5,6 @@ var Child = /*#__PURE__*/ function(Base1) {
         _class_call_check(this, Child);
         var _this;
         return _possible_constructor_return(_this, {});
-        return _possible_constructor_return(_this);
     }
     return Child;
 }(Base);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2015_classes.rs/spec_nested_class_super_call_in_key.js

@@ -29,7 +29,6 @@ var Outer = /*#__PURE__*/ function(Hello) {
             return Inner;
         }();
         return _possible_constructor_return(_this, new Inner());
-        return _this;
     }
     return Outer;
 }(Hello);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2015_classes.rs/spec_nested_class_super_property_in_key.js

@@ -35,7 +35,6 @@ var Outer = /*#__PURE__*/ function(Hello) {
             return Inner;
         }();
         return _possible_constructor_return(_this, new Inner());
-        return _this;
     }
     return Outer;
 }(Hello);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2015_classes.rs/spec_nested_object_super_call_in_key.js

@@ -19,7 +19,6 @@ var Outer = /*#__PURE__*/ function(Hello) {
             }
         };
         return _possible_constructor_return(_this, Inner);
-        return _this;
     }
     return Outer;
 }(Hello);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2015_classes.rs/spec_nested_object_super_property_in_key.js

@@ -26,7 +26,6 @@ var Outer = /*#__PURE__*/ function(Hello) {
             }
         };
         return _possible_constructor_return(_this, Inner);
-        return _this;
     }
     return Outer;
 }(Hello);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2015_classes.rs/spec_this_not_allowed_before_super_in_derived_classes_5.js

@@ -5,7 +5,7 @@ var Foo = /*#__PURE__*/ function(Bar1) {
         _class_call_check(this, Foo);
         var _this;
         Foo[_assert_this_initialized(_this)];
-        return _possible_constructor_return(_this);
+        return _assert_this_initialized(_this);
     }
     return Foo;
 }(Bar);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2022_class_properties.rs/nested_class_super_call_in_key.js

@@ -19,7 +19,6 @@ var Outer = /*#__PURE__*/ function(Hello) {
             _define_property(this, _ref, "hello");
         };
         return _possible_constructor_return(_this, new Inner());
-        return _this;
     }
     return Outer;
 }(Hello);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2022_class_properties.rs/nested_class_super_property_in_key.js

@@ -26,7 +26,6 @@ var Outer = /*#__PURE__*/ function(Hello) {
             _define_property(this, _super_toString, 'hello');
         };
         return _possible_constructor_return(_this, new Inner());
-        return _this;
     }
     return Outer;
 }(Hello);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2022_class_properties.rs/private_derived_multiple_supers.js

@@ -16,7 +16,7 @@ var Foo = /*#__PURE__*/ function(Bar1) {
                 value: "foo"
             });
         }
-        return _possible_constructor_return(_this);
+        return _assert_this_initialized(_this);
     }
     return Foo;
 }(Bar);

crates/swc_ecma_transforms_compat/tests/__swc_snapshots__/tests/es2022_class_properties.rs/public_derived_multiple_supers.js

@@ -9,7 +9,7 @@ var Foo = /*#__PURE__*/ function(Bar1) {
         } else {
             _this = _call_super(this, Foo), _define_property(_this, "bar", "foo");
         }
-        return _possible_constructor_return(_this);
+        return _assert_this_initialized(_this);
     }
     return Foo;
 }(Bar);