Mark class prototype as read-only (#12115)

* initial code 2 fix the issue #2025 * Mark class prototype as read-only * Update fixtures * Fix failure * Update Babel 8 fixtures * Disable in loose mode * Update fixtures Co-authored-by: Nicolò Ribaudo <nicolo.ribaudo@gmail.com>
2021-12-10 23:44:48 +03:00
parent 39080492f4
commit c59870c526
221 changed files with 490 additions and 458 deletions
--- a/packages/babel-plugin-transform-classes/src/transformClass.ts
+++ b/packages/babel-plugin-transform-classes/src/transformClass.ts
@@ -58,6 +58,7 @@ export default function transformClass(
    superThises: [],
    pushedConstructor: false,
    pushedInherits: false,
+    pushedCreateClass: false,
    protoAlias: null,
    isLoose: false,

@@ -93,6 +94,10 @@ export default function transformClass(
    },
  ]);

+  function createClassHelper(args) {
+    return t.callExpression(classState.file.addHelper("createClass"), args);
+  }
+
  /**
   * Creates a class constructor or bail out if there is none
   */
@@ -240,11 +245,8 @@ export default function transformClass(
      }
      args = args.slice(0, lastNonNullIndex + 1);

-      body.push(
-        t.expressionStatement(
-          t.callExpression(classState.file.addHelper("createClass"), args),
-        ),
-      );
+      body.push(t.expressionStatement(createClassHelper(args)));
+      classState.pushedCreateClass = true;
    }
  }

@@ -737,10 +739,16 @@ export default function transformClass(

    if (constructorOnly) {
      // named class with only a constructor
-      return t.toExpression(body[0]);
+      const expr = t.toExpression(body[0]);
+      return classState.isLoose ? expr : createClassHelper([expr]);
    }

-    body.push(t.returnStatement(t.cloneNode(classState.classRef)));
+    let returnArg = t.cloneNode(classState.classRef);
+    if (!classState.pushedCreateClass && !classState.isLoose) {
+      returnArg = createClassHelper([returnArg]);
+    }
+
+    body.push(t.returnStatement(returnArg));
    const container = t.arrowFunctionExpression(
      closureParams,
      t.blockStatement(body, directives),
--- a/packages/babel-plugin-transform-classes/test/fixtures/assumption-constantSuper/accessing-super-class/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/assumption-constantSuper/accessing-super-class/output.js
@@ -26,5 +26,5 @@ var Test = /*#__PURE__*/function (_Foo) {
    return _this;
  }

-  return Test;
+  return babelHelpers.createClass(Test);
 }(Foo);
--- a/packages/babel-plugin-transform-classes/test/fixtures/assumption-constantSuper/accessing-super-properties/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/assumption-constantSuper/accessing-super-properties/output.js
@@ -15,5 +15,5 @@ var Test = /*#__PURE__*/function (_Foo) {
    return _this;
  }

-  return Test;
+  return babelHelpers.createClass(Test);
 }(Foo);
--- a/packages/babel-plugin-transform-classes/test/fixtures/assumption-constantSuper/super-function-fallback/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/assumption-constantSuper/super-function-fallback/output.js
@@ -1,6 +1,6 @@
-var Test = function Test() {
+var Test = /*#__PURE__*/babelHelpers.createClass(function Test() {
  "use strict";

  babelHelpers.classCallCheck(this, Test);
  Object.prototype.hasOwnProperty.call(this, "test");
-};
+});
--- a/packages/babel-plugin-transform-classes/test/fixtures/assumption-noCallClass/class/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/assumption-noCallClass/class/output.js
@@ -1,3 +1,3 @@
-var A = function A() {
+var A = /*#__PURE__*/babelHelpers.createClass(function A() {
  "use strict";
-};
+});
--- a/packages/babel-plugin-transform-classes/test/fixtures/assumption-noCallClass/with-constructor/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/assumption-noCallClass/with-constructor/output.js
@@ -1,8 +1,8 @@
-var A = function A() {
+var A = /*#__PURE__*/babelHelpers.createClass(function A() {
  "use strict";

  console.log('a');
-};
+});

 var B = /*#__PURE__*/function () {
  "use strict";
--- a/packages/babel-plugin-transform-classes/test/fixtures/assumption-noCallClass/with-superClass/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/assumption-noCallClass/with-superClass/output.js
@@ -1,6 +1,6 @@
-var B = function B() {
+var B = /*#__PURE__*/babelHelpers.createClass(function B() {
  "use strict";
-};
+});

 var A = /*#__PURE__*/function (_B) {
  "use strict";
@@ -16,5 +16,5 @@ var A = /*#__PURE__*/function (_B) {
    return babelHelpers.possibleConstructorReturn(_this);
  }

-  return A;
+  return babelHelpers.createClass(A);
 }(B);
--- a/packages/babel-plugin-transform-classes/test/fixtures/assumption-setClassMethods/literal-key/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/assumption-setClassMethods/literal-key/output.js
@@ -9,5 +9,5 @@ var Foo = /*#__PURE__*/function () {

  _proto["bar"] = function bar() {};

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }();
--- a/packages/babel-plugin-transform-classes/test/fixtures/assumption-setClassMethods/method-reuse-prototype/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/assumption-setClassMethods/method-reuse-prototype/output.js
@@ -13,5 +13,5 @@ var Test = /*#__PURE__*/function () {

  _proto.c = function c() {};

-  return Test;
+  return babelHelpers.createClass(Test);
 }();
--- a/packages/babel-plugin-transform-classes/test/fixtures/assumption-setClassMethods/program-with-use-strict-directive/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/assumption-setClassMethods/program-with-use-strict-directive/output.js
@@ -9,5 +9,5 @@ var Foo = /*#__PURE__*/function () {

  _proto.method = function method() {};

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }();
--- a/packages/babel-plugin-transform-classes/test/fixtures/assumption-superIsCallableConstructor/super-class-id-member-expression/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/assumption-superIsCallableConstructor/super-class-id-member-expression/output.js
@@ -8,7 +8,7 @@ var BaseController = /*#__PURE__*/function (_Chaplin$Controller) {
    return _Chaplin$Controller.apply(this, arguments) || this;
  }

-  return BaseController;
+  return babelHelpers.createClass(BaseController);
 }(Chaplin.Controller);

 var BaseController2 = /*#__PURE__*/function (_Chaplin$Controller$A) {
@@ -21,5 +21,5 @@ var BaseController2 = /*#__PURE__*/function (_Chaplin$Controller$A) {
    return _Chaplin$Controller$A.apply(this, arguments) || this;
  }

-  return BaseController2;
+  return babelHelpers.createClass(BaseController2);
 }(Chaplin.Controller.Another);
--- a/packages/babel-plugin-transform-classes/test/fixtures/assumption-superIsCallableConstructor/super-class-this-usage/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/assumption-superIsCallableConstructor/super-class-this-usage/output.js
@@ -13,5 +13,5 @@ var Test = /*#__PURE__*/function (_Foo) {
    return _this;
  }

-  return Test;
+  return babelHelpers.createClass(Test);
 }(Foo);
--- a/packages/babel-plugin-transform-classes/test/fixtures/assumption-superIsCallableConstructor/super-class/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/assumption-superIsCallableConstructor/super-class/output.js
@@ -8,5 +8,5 @@ var Test = /*#__PURE__*/function (_Foo) {
    return _Foo.apply(this, arguments) || this;
  }

-  return Test;
+  return babelHelpers.createClass(Test);
 }(Foo);
--- a/packages/babel-plugin-transform-classes/test/fixtures/exec/prototype-descriptor.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/exec/prototype-descriptor.js
@@ -0,0 +1,16 @@
+class A {}
+class B extends A {}
+
+expect(Object.getOwnPropertyDescriptor(A, "prototype")).toEqual({
+  value: A.prototype,
+  configurable: false,
+  enumerable: false,
+  writable: false,
+});
+
+expect(Object.getOwnPropertyDescriptor(B, "prototype")).toEqual({
+  value: B.prototype,
+  configurable: false,
+  enumerable: false,
+  writable: false,
+});
--- a/packages/babel-plugin-transform-classes/test/fixtures/extend-builtins/shadowed/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/extend-builtins/shadowed/output.js
@@ -1,8 +1,8 @@
-let Array = function Array() {
+let Array = /*#__PURE__*/babelHelpers.createClass(function Array() {
  "use strict";

  babelHelpers.classCallCheck(this, Array);
-};
+});

 let List = /*#__PURE__*/function (_Array) {
  "use strict";
@@ -16,5 +16,5 @@ let List = /*#__PURE__*/function (_Array) {
    return _super.apply(this, arguments);
  }

-  return List;
+  return babelHelpers.createClass(List);
 }(Array);
--- a/packages/babel-plugin-transform-classes/test/fixtures/extend-builtins/spec/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/extend-builtins/spec/output.js
@@ -10,5 +10,5 @@ var List = /*#__PURE__*/function (_Array) {
    return _super.apply(this, arguments);
  }

-  return List;
+  return babelHelpers.createClass(List);
 }( /*#__PURE__*/babelHelpers.wrapNativeSuper(Array));
--- a/packages/babel-plugin-transform-classes/test/fixtures/get-set/call-semantics-not-defined-on-parent/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/get-set/call-semantics-not-defined-on-parent/output.js
@@ -1,8 +1,8 @@
 "use strict";

-let Base = function Base() {
+let Base = /*#__PURE__*/babelHelpers.createClass(function Base() {
  babelHelpers.classCallCheck(this, Base);
-};
+});

 let Obj = /*#__PURE__*/function (_Base) {
  babelHelpers.inherits(Obj, _Base);
--- a/packages/babel-plugin-transform-classes/test/fixtures/get-set/get-semantics-data-defined-on-parent/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/get-set/get-semantics-data-defined-on-parent/output.js
@@ -1,9 +1,8 @@
 "use strict";

-let Base = function Base() {
+let Base = /*#__PURE__*/babelHelpers.createClass(function Base() {
  babelHelpers.classCallCheck(this, Base);
-};
-
+});
 Base.prototype.test = 1;

 let Obj = /*#__PURE__*/function (_Base) {
--- a/packages/babel-plugin-transform-classes/test/fixtures/get-set/get-semantics-not-defined-on-parent/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/get-set/get-semantics-not-defined-on-parent/output.js
@@ -1,8 +1,8 @@
 "use strict";

-let Base = function Base() {
+let Base = /*#__PURE__*/babelHelpers.createClass(function Base() {
  babelHelpers.classCallCheck(this, Base);
-};
+});

 let Obj = /*#__PURE__*/function (_Base) {
  babelHelpers.inherits(Obj, _Base);
--- a/packages/babel-plugin-transform-classes/test/fixtures/get-set/memoized-assign/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/get-set/memoized-assign/output.js
@@ -1,9 +1,8 @@
 "use strict";

-let Base = function Base() {
+let Base = /*#__PURE__*/babelHelpers.createClass(function Base() {
  babelHelpers.classCallCheck(this, Base);
-};
-
+});
 Object.defineProperty(Base.prototype, 0, {
  value: 0,
  writable: true,
--- a/packages/babel-plugin-transform-classes/test/fixtures/get-set/memoized-update/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/get-set/memoized-update/output.js
@@ -1,9 +1,8 @@
 "use strict";

-let Base = function Base() {
+let Base = /*#__PURE__*/babelHelpers.createClass(function Base() {
  babelHelpers.classCallCheck(this, Base);
-};
-
+});
 Object.defineProperty(Base.prototype, 0, {
  value: 0,
  writable: true,
--- a/packages/babel-plugin-transform-classes/test/fixtures/get-set/set-semantics-data-defined-on-parent/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/get-set/set-semantics-data-defined-on-parent/output.js
@@ -1,9 +1,8 @@
 "use strict";

-let Base = function Base() {
+let Base = /*#__PURE__*/babelHelpers.createClass(function Base() {
  babelHelpers.classCallCheck(this, Base);
-};
-
+});
 Object.defineProperty(Base.prototype, 'test', {
  value: 1,
  writable: true,
--- a/packages/babel-plugin-transform-classes/test/fixtures/get-set/set-semantics-not-defined-on-parent-data-on-obj/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/get-set/set-semantics-not-defined-on-parent-data-on-obj/output.js
@@ -1,8 +1,8 @@
 "use strict";

-let Base = function Base() {
+let Base = /*#__PURE__*/babelHelpers.createClass(function Base() {
  babelHelpers.classCallCheck(this, Base);
-};
+});

 let Obj = /*#__PURE__*/function (_Base) {
  babelHelpers.inherits(Obj, _Base);
--- a/packages/babel-plugin-transform-classes/test/fixtures/get-set/set-semantics-not-defined-on-parent-getter-on-obj/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/get-set/set-semantics-not-defined-on-parent-getter-on-obj/output.js
@@ -1,8 +1,8 @@
 "use strict";

-let Base = function Base() {
+let Base = /*#__PURE__*/babelHelpers.createClass(function Base() {
  babelHelpers.classCallCheck(this, Base);
-};
+});

 let Obj = /*#__PURE__*/function (_Base) {
  babelHelpers.inherits(Obj, _Base);
--- a/packages/babel-plugin-transform-classes/test/fixtures/get-set/set-semantics-not-defined-on-parent-not-on-obj/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/get-set/set-semantics-not-defined-on-parent-not-on-obj/output.js
@@ -1,8 +1,8 @@
 "use strict";

-let Base = function Base() {
+let Base = /*#__PURE__*/babelHelpers.createClass(function Base() {
  babelHelpers.classCallCheck(this, Base);
-};
+});

 let Obj = /*#__PURE__*/function (_Base) {
  babelHelpers.inherits(Obj, _Base);
--- a/packages/babel-plugin-transform-classes/test/fixtures/get-set/set-semantics-not-defined-on-parent-setter-on-obj/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/get-set/set-semantics-not-defined-on-parent-setter-on-obj/output.js
@@ -1,9 +1,8 @@
 "use strict";

-let Base = function Base() {
+let Base = /*#__PURE__*/babelHelpers.createClass(function Base() {
  babelHelpers.classCallCheck(this, Base);
-};
-
+});
 let value = 2;

 let Obj = /*#__PURE__*/function (_Base) {
--- a/packages/babel-plugin-transform-classes/test/fixtures/regression/2941/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/regression/2941/output.js
@@ -5,8 +5,8 @@ Object.defineProperty(exports, "__esModule", {
 });
 exports["default"] = void 0;

-var _default = function _default() {
+var _default = /*#__PURE__*/babelHelpers.createClass(function _default() {
  babelHelpers.classCallCheck(this, _default);
-};
+});

 exports["default"] = _default;
--- a/packages/babel-plugin-transform-classes/test/fixtures/regression/3028/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/regression/3028/output.js
@@ -4,10 +4,9 @@ Object.defineProperty(exports, "__esModule", {
  value: true
 });
 exports["default"] = void 0;
-
-var b = function b() {
+var b = /*#__PURE__*/babelHelpers.createClass(function b() {
  babelHelpers.classCallCheck(this, b);
-};
+});

 var a1 = /*#__PURE__*/function (_b) {
  babelHelpers.inherits(a1, _b);
@@ -27,7 +26,7 @@ var a1 = /*#__PURE__*/function (_b) {
    return _this;
  }

-  return a1;
+  return babelHelpers.createClass(a1);
 }(b);

 var a2 = /*#__PURE__*/function (_b2) {
@@ -48,7 +47,7 @@ var a2 = /*#__PURE__*/function (_b2) {
    return _this2;
  }

-  return a2;
+  return babelHelpers.createClass(a2);
 }(b);

 exports["default"] = a2;
--- a/packages/babel-plugin-transform-classes/test/fixtures/regression/5817/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/regression/5817/output.js
@@ -22,5 +22,5 @@ var A = /*#__PURE__*/function (_B) {
    return _this;
  }

-  return A;
+  return babelHelpers.createClass(A);
 }(B);
--- a/packages/babel-plugin-transform-classes/test/fixtures/regression/8499/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/regression/8499/output.js
@@ -25,7 +25,7 @@ try {
      return _super.apply(this, arguments);
    }

-    return CustomElement;
+    return babelHelpers.createClass(CustomElement);
  }( /*#__PURE__*/babelHelpers.wrapNativeSuper(HTMLElement));

  ;
--- a/packages/babel-plugin-transform-classes/test/fixtures/regression/T2494/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/regression/T2494/output.js
@@ -11,6 +11,6 @@ var x = {
      return _super.apply(this, arguments);
    }

-    return _class;
+    return babelHelpers.createClass(_class);
  }(Foo)
 };
--- a/packages/babel-plugin-transform-classes/test/fixtures/regression/T2997/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/regression/T2997/output.js
@@ -1,8 +1,8 @@
-var A = function A() {
+var A = /*#__PURE__*/babelHelpers.createClass(function A() {
  "use strict";

  babelHelpers.classCallCheck(this, A);
-};
+});

 var B = /*#__PURE__*/function (_A) {
  "use strict";
@@ -18,5 +18,5 @@ var B = /*#__PURE__*/function (_A) {
    return babelHelpers.possibleConstructorReturn(_this, _this = _super.call(this));
  }

-  return B;
+  return babelHelpers.createClass(B);
 }(A);
--- a/packages/babel-plugin-transform-classes/test/fixtures/regression/T7537/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/regression/T7537/output.js
@@ -1,8 +1,8 @@
-var B = function B() {
+var B = /*#__PURE__*/babelHelpers.createClass(function B() {
  "use strict";

  babelHelpers.classCallCheck(this, B);
-};
+});

 var A = /*#__PURE__*/function (_B) {
  "use strict";
@@ -19,5 +19,5 @@ var A = /*#__PURE__*/function (_B) {
    return babelHelpers.possibleConstructorReturn(_this);
  }

-  return A;
+  return babelHelpers.createClass(A);
 }(B);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/accessing-super-properties/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/accessing-super-properties/output.js
@@ -15,5 +15,5 @@ var Test = /*#__PURE__*/function (_Foo) {
    return _this;
  }

-  return Test;
+  return babelHelpers.createClass(Test);
 }(Foo);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/accessing-super-property-optional-chain/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/accessing-super-property-optional-chain/output.js
@@ -16,5 +16,5 @@ var Test = /*#__PURE__*/function (_Foo) {
    return babelHelpers.possibleConstructorReturn(_this);
  }

-  return Test;
+  return babelHelpers.createClass(Test);
 }(Foo);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/constructor-binding-collision/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/constructor-binding-collision/output.js
@@ -1,9 +1,8 @@
-var Example = function Example() {
+var Example = /*#__PURE__*/babelHelpers.createClass(function Example() {
  "use strict";

  babelHelpers.classCallCheck(this, Example);

  var _Example;
-};
-
+});
 var t = new Example();
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/constructor-only/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/constructor-only/output.js
@@ -1,5 +1,5 @@
-var Foo = function Foo() {
+var Foo = /*#__PURE__*/babelHelpers.createClass(function Foo() {
  "use strict";

  babelHelpers.classCallCheck(this, Foo);
-};
+});
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/constructor/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/constructor/output.js
@@ -1,9 +1,9 @@
-var Test = function Test() {
+var Test = /*#__PURE__*/babelHelpers.createClass(function Test() {
  "use strict";

  babelHelpers.classCallCheck(this, Test);
  this.state = "test";
-};
+});

 var Foo = /*#__PURE__*/function (_Bar) {
  "use strict";
@@ -21,10 +21,10 @@ var Foo = /*#__PURE__*/function (_Bar) {
    return _this;
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);

-var ConstructorScoping = function ConstructorScoping() {
+var ConstructorScoping = /*#__PURE__*/babelHelpers.createClass(function ConstructorScoping() {
  "use strict";

  babelHelpers.classCallCheck(this, ConstructorScoping);
@@ -32,4 +32,4 @@ var ConstructorScoping = function ConstructorScoping() {
  {
    var _bar;
  }
-};
+});
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/delay-arrow-function-for-bare-super-derived/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/delay-arrow-function-for-bare-super-derived/output.js
@@ -14,5 +14,5 @@ var Foo = /*#__PURE__*/function (_Bar) {
    });
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-must-call-super-2/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-must-call-super-2/output.js
@@ -13,5 +13,5 @@ var Foo = /*#__PURE__*/function (_Bar) {
    return babelHelpers.possibleConstructorReturn(_this);
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-must-call-super-3/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-must-call-super-3/output.js
@@ -16,5 +16,5 @@ var Foo = /*#__PURE__*/function (_Bar) {
    return babelHelpers.possibleConstructorReturn(_this);
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-must-call-super-4/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-must-call-super-4/output.js
@@ -15,5 +15,5 @@ var Foo = /*#__PURE__*/function (_Bar) {
    return babelHelpers.possibleConstructorReturn(_this);
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-must-call-super/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-must-call-super/output.js
@@ -12,5 +12,5 @@ var Foo = /*#__PURE__*/function (_Bar) {
    return babelHelpers.possibleConstructorReturn(_this);
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-no-primitive-return/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-no-primitive-return/output.js
@@ -13,5 +13,5 @@ var Foo = /*#__PURE__*/function (_Bar) {
    return babelHelpers.possibleConstructorReturn(_this, 3);
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-no-super-return-falsey/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-no-super-return-falsey/output.js
@@ -12,5 +12,5 @@ var Child = /*#__PURE__*/function (_Base) {
    return babelHelpers.possibleConstructorReturn(_this, false);
  }

-  return Child;
+  return babelHelpers.createClass(Child);
 }(Base);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-no-super-return-object/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-no-super-return-object/output.js
@@ -12,5 +12,5 @@ var Child = /*#__PURE__*/function (_Base) {
    return babelHelpers.possibleConstructorReturn(_this, {});
  }

-  return Child;
+  return babelHelpers.createClass(Child);
 }(Base);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/export-default/output.mjs
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/export-default/output.mjs
@@ -1,5 +1,4 @@
-var Foo = function Foo() {
+var Foo = /*#__PURE__*/babelHelpers.createClass(function Foo() {
  babelHelpers.classCallCheck(this, Foo);
-};
-
+});
 export { Foo as default };
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/export-super-class/output.mjs
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/export-super-class/output.mjs
@@ -8,7 +8,7 @@ var _default = /*#__PURE__*/function (_A) {
    return _super.apply(this, arguments);
  }

-  return _default;
+  return babelHelpers.createClass(_default);
 }(A);

 export { _default as default };
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/inferred-expression-name/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/inferred-expression-name/output.js
@@ -1,7 +1,7 @@
 var o = {
-  foo: function foo() {
+  foo: /*#__PURE__*/babelHelpers.createClass(function foo() {
    "use strict";

    babelHelpers.classCallCheck(this, foo);
-  }
+  })
 };
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/name-collisions-with-class-ref-in-computed-key/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/name-collisions-with-class-ref-in-computed-key/output.js
@@ -30,5 +30,5 @@ var Foo = /*#__PURE__*/function (_Bar) {
    return _this;
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/nested-class-super-call-in-key/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/nested-class-super-call-in-key/output.js
@@ -1,6 +1,6 @@
 "use strict";

-var Hello = function Hello() {
+var Hello = /*#__PURE__*/babelHelpers.createClass(function Hello() {
  babelHelpers.classCallCheck(this, Hello);
  return {
    toString() {
@@ -8,7 +8,7 @@ var Hello = function Hello() {
    }

  };
-};
+});

 var Outer = /*#__PURE__*/function (_Hello) {
  babelHelpers.inherits(Outer, _Hello);
@@ -37,7 +37,7 @@ var Outer = /*#__PURE__*/function (_Hello) {
    return babelHelpers.possibleConstructorReturn(_this, new Inner());
  }

-  return Outer;
+  return babelHelpers.createClass(Outer);
 }(Hello);

 expect(new Outer().hello()).toBe('hello');
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/nested-class-super-property-in-key/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/nested-class-super-property-in-key/output.js
@@ -42,7 +42,7 @@ var Outer = /*#__PURE__*/function (_Hello) {
    return babelHelpers.possibleConstructorReturn(_this, new Inner());
  }

-  return Outer;
+  return babelHelpers.createClass(Outer);
 }(Hello);

 expect(new Outer().hello()).toBe('hello');
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/nested-object-super-call-in-key/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/nested-object-super-call-in-key/output.js
@@ -1,6 +1,6 @@
 "use strict";

-var Hello = function Hello() {
+var Hello = /*#__PURE__*/babelHelpers.createClass(function Hello() {
  babelHelpers.classCallCheck(this, Hello);
  return {
    toString() {
@@ -8,7 +8,7 @@ var Hello = function Hello() {
    }

  };
-};
+});

 var Outer = /*#__PURE__*/function (_Hello) {
  babelHelpers.inherits(Outer, _Hello);
@@ -28,7 +28,7 @@ var Outer = /*#__PURE__*/function (_Hello) {
    return babelHelpers.possibleConstructorReturn(_this, Inner);
  }

-  return Outer;
+  return babelHelpers.createClass(Outer);
 }(Hello);

 expect(new Outer().hello()).toBe('hello');
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/nested-object-super-property-in-key/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/nested-object-super-property-in-key/output.js
@@ -33,7 +33,7 @@ var Outer = /*#__PURE__*/function (_Hello) {
    return babelHelpers.possibleConstructorReturn(_this, Inner);
  }

-  return Outer;
+  return babelHelpers.createClass(Outer);
 }(Hello);

 expect(new Outer().hello()).toBe('hello');
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/plain-class/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/plain-class/output.js
@@ -1,5 +1,5 @@
-var Test = function Test() {
+var Test = /*#__PURE__*/babelHelpers.createClass(function Test() {
  "use strict";

  babelHelpers.classCallCheck(this, Test);
-};
+});
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/preserves-directives/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/preserves-directives/output.js
@@ -1,25 +1,23 @@
-var MyCtrl = function MyCtrl(a) {
+var MyCtrl = /*#__PURE__*/babelHelpers.createClass(function MyCtrl(a) {
  "any directive prologue";
  "use strict";

  babelHelpers.classCallCheck(this, MyCtrl);
  foo;
-};
-
-var MyCtrl2 = function MyCtrl2(a) {
+});
+var MyCtrl2 = /*#__PURE__*/babelHelpers.createClass(function MyCtrl2(a) {
  "a";
  "b";
  "use strict";

  babelHelpers.classCallCheck(this, MyCtrl2);
  foo;
-};
-
-var MyCtrl3 = function MyCtrl3(a) {
+});
+var MyCtrl3 = /*#__PURE__*/babelHelpers.createClass(function MyCtrl3(a) {
  "a";
  "use strict";

  babelHelpers.classCallCheck(this, MyCtrl3);
  foo;
  "b";
-};
+});
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/statement/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/statement/output.js
@@ -1,16 +1,15 @@
-var BaseView = function BaseView() {
+var BaseView = /*#__PURE__*/babelHelpers.createClass(function BaseView() {
  "use strict";

  babelHelpers.classCallCheck(this, BaseView);
  this.autoRender = true;
-};
-
-var BaseView = function BaseView() {
+});
+var BaseView = /*#__PURE__*/babelHelpers.createClass(function BaseView() {
  "use strict";

  babelHelpers.classCallCheck(this, BaseView);
  this.autoRender = true;
-};
+});

 var BaseView = /*#__PURE__*/function () {
  "use strict";
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/super-class-anonymous/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/super-class-anonymous/output.js
@@ -10,7 +10,7 @@ var TestEmpty = /*#__PURE__*/function (_ref) {
    return _super.apply(this, arguments);
  }

-  return TestEmpty;
+  return babelHelpers.createClass(TestEmpty);
 }( /*#__PURE__*/function () {
  "use strict";

@@ -18,7 +18,7 @@ var TestEmpty = /*#__PURE__*/function (_ref) {
    babelHelpers.classCallCheck(this, _class);
  }

-  return _class;
+  return babelHelpers.createClass(_class);
 }());

 var TestConstructorOnly = /*#__PURE__*/function (_ref2) {
@@ -33,7 +33,7 @@ var TestConstructorOnly = /*#__PURE__*/function (_ref2) {
    return _super2.apply(this, arguments);
  }

-  return TestConstructorOnly;
+  return babelHelpers.createClass(TestConstructorOnly);
 }( /*#__PURE__*/function () {
  "use strict";

@@ -41,7 +41,7 @@ var TestConstructorOnly = /*#__PURE__*/function (_ref2) {
    babelHelpers.classCallCheck(this, _class2);
  }

-  return _class2;
+  return babelHelpers.createClass(_class2);
 }());

 var TestMethodOnly = /*#__PURE__*/function (_ref3) {
@@ -56,7 +56,7 @@ var TestMethodOnly = /*#__PURE__*/function (_ref3) {
    return _super3.apply(this, arguments);
  }

-  return TestMethodOnly;
+  return babelHelpers.createClass(TestMethodOnly);
 }( /*#__PURE__*/function () {
  "use strict";

@@ -83,7 +83,7 @@ var TestConstructorAndMethod = /*#__PURE__*/function (_ref4) {
    return _super4.apply(this, arguments);
  }

-  return TestConstructorAndMethod;
+  return babelHelpers.createClass(TestConstructorAndMethod);
 }( /*#__PURE__*/function () {
  "use strict";

@@ -110,7 +110,7 @@ var TestMultipleMethods = /*#__PURE__*/function (_ref5) {
    return _super5.apply(this, arguments);
  }

-  return TestMultipleMethods;
+  return babelHelpers.createClass(TestMultipleMethods);
 }( /*#__PURE__*/function () {
  "use strict";

--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/super-class-id-member-expression/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/super-class-id-member-expression/output.js
@@ -10,7 +10,7 @@ var BaseController = /*#__PURE__*/function (_Chaplin$Controller) {
    return _super.apply(this, arguments);
  }

-  return BaseController;
+  return babelHelpers.createClass(BaseController);
 }(Chaplin.Controller);

 var BaseController2 = /*#__PURE__*/function (_Chaplin$Controller$A) {
@@ -25,5 +25,5 @@ var BaseController2 = /*#__PURE__*/function (_Chaplin$Controller$A) {
    return _super2.apply(this, arguments);
  }

-  return BaseController2;
+  return babelHelpers.createClass(BaseController2);
 }(Chaplin.Controller.Another);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/super-class/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/super-class/output.js
@@ -10,5 +10,5 @@ var Test = /*#__PURE__*/function (_Foo) {
    return _super.apply(this, arguments);
  }

-  return Test;
+  return babelHelpers.createClass(Test);
 }(Foo);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/super-function-fallback/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/super-function-fallback/output.js
@@ -1,6 +1,6 @@
-var Test = function Test() {
+var Test = /*#__PURE__*/babelHelpers.createClass(function Test() {
  "use strict";

  babelHelpers.classCallCheck(this, Test);
  babelHelpers.get(babelHelpers.getPrototypeOf(Test.prototype), "hasOwnProperty", this).call(this, "test");
-};
+});
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-bare-super-inline/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-bare-super-inline/output.js
@@ -13,5 +13,5 @@ var Foo = /*#__PURE__*/function (_Bar) {
    return _this;
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-bare-super/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-bare-super/output.js
@@ -13,5 +13,5 @@ var Foo = /*#__PURE__*/function (_Bar) {
    return _this = _super.call(this);
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-in-lambda-2/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-in-lambda-2/output.js
@@ -16,5 +16,5 @@ var Foo = /*#__PURE__*/function (_Bar) {
    return _this = _super.call(this);
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-in-lambda-3/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-in-lambda-3/output.js
@@ -17,5 +17,5 @@ var Foo = /*#__PURE__*/function (_Bar) {
    return _this;
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-in-lambda/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-in-lambda/output.js
@@ -15,5 +15,5 @@ var Foo = /*#__PURE__*/function (_Bar) {
    return _this = _super.call(this);
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-in-prop-exression/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-in-prop-exression/output.js
@@ -13,5 +13,5 @@ var Foo = /*#__PURE__*/function (_Bar) {
    return _this;
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/this-not-allowed-before-super-in-derived-classes-2/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/this-not-allowed-before-super-in-derived-classes-2/output.js
@@ -12,5 +12,5 @@ var Foo = /*#__PURE__*/function (_Bar) {
    return _this = _super.call(this, babelHelpers.assertThisInitialized(_this));
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/this-not-allowed-before-super-in-derived-classes-3/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/this-not-allowed-before-super-in-derived-classes-3/output.js
@@ -16,5 +16,5 @@ var Foo = /*#__PURE__*/function (_Bar) {
    return _this = _super.call(this);
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/this-not-allowed-before-super-in-derived-classes-4/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/this-not-allowed-before-super-in-derived-classes-4/output.js
@@ -17,5 +17,5 @@ var Foo = /*#__PURE__*/function (_Bar) {
    return _this;
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/this-not-allowed-before-super-in-derived-classes-5/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/this-not-allowed-before-super-in-derived-classes-5/output.js
@@ -13,5 +13,5 @@ var Foo = /*#__PURE__*/function (_Bar) {
    return babelHelpers.possibleConstructorReturn(_this);
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/this-not-allowed-before-super-in-derived-classes/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/this-not-allowed-before-super-in-derived-classes/output.js
@@ -13,5 +13,5 @@ var Foo = /*#__PURE__*/function (_Bar) {
    return _this = _super.call(this);
  }

-  return Foo;
+  return babelHelpers.createClass(Foo);
 }(Bar);