Add "use strict" directive (#7411)

* #7349
- Add "use strict" directive to transformed class bodies

* Update tests (#7349)

* Add test for program with use strict directive (#7349)

* Update tests (#7349)

* Update source mapping (#7349)

* Add test for parent blockStatement with use strict directive (#7349)

* Update tests (#7349)

* Update tests (#7349)

* Update tests (#7349)

* Add test for constructor-only class (#7349)

* Constructor only classes are strict, too

But constructor only that use non-simple parameters must use a strict function wrapper.

* Fix test

* Wrapper not needed if class is already strict

* Revert change to lerna.json

packages/babel-plugin-transform-classes/test/fixtures/extend-builtins/loose/output.js

@@ -11,6 +11,8 @@ function _getPrototypeOf(o) { _getPrototypeOf = Object.getPrototypeOf || functio
 var List =
 /*#__PURE__*/
 function (_Array) {
+  "use strict";
+
   _inheritsLoose(List, _Array);
 
   function List() {

packages/babel-plugin-transform-classes/test/fixtures/extend-builtins/shadowed/output.js

@@ -1,10 +1,14 @@
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+  "use strict";
+
   babelHelpers.classCallCheck(this, Array);
 };
 
 let List =
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+  "use strict";
+
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packages/babel-plugin-transform-classes/test/fixtures/extend-builtins/spec/output.js

@@ -17,6 +17,8 @@ function _getPrototypeOf(o) { _getPrototypeOf = Object.getPrototypeOf || functio
 var List =
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 function (_Array) {
+  "use strict";
+
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packages/babel-plugin-transform-classes/test/fixtures/loose-classCallCheck/class/output.js

@@ -1 +1,3 @@
-let A = function A() {};
+let A = function A() {
+  "use strict";
+};

packages/babel-plugin-transform-classes/test/fixtures/loose-classCallCheck/with-constructor/output.js

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+  "use strict";
+
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+  "use strict";
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packages/babel-plugin-transform-classes/test/fixtures/loose-classCallCheck/with-superClass/output.js

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 function _inheritsLoose(subClass, superClass) { subClass.prototype = Object.create(superClass.prototype); subClass.prototype.constructor = subClass; subClass.__proto__ = superClass; }
 
-let B = function B() {};
+let B = function B() {
+  "use strict";
+};
 
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+  "use strict";
+
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packages/babel-plugin-transform-classes/test/fixtures/loose/accessing-super-class/output.js

@@ -1,6 +1,8 @@
 var Test =
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 function (_Foo) {
+  "use strict";
+
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packages/babel-plugin-transform-classes/test/fixtures/loose/accessing-super-properties/output.js

@@ -1,6 +1,8 @@
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 /*#__PURE__*/
 function (_Foo) {
+  "use strict";
+
   babelHelpers.inheritsLoose(Test, _Foo);
 
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packages/babel-plugin-transform-classes/test/fixtures/loose/blockstatement-with-use-strict-directive/input.js

@@ -0,0 +1,6 @@
+function t() {
+    "use strict";
+    class Foo {
+      method() {}
+    }
+  }

packages/babel-plugin-transform-classes/test/fixtures/loose/blockstatement-with-use-strict-directive/output.js

@@ -0,0 +1,15 @@
+function t() {
+  "use strict";
+
+  var Foo =
+  /*#__PURE__*/
+  function () {
+    function Foo() {}
+
+    var _proto = Foo.prototype;
+
+    _proto.method = function method() {};
+
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+  }();
+}

packages/babel-plugin-transform-classes/test/fixtures/loose/calling-super-properties/output.js

@@ -1,6 +1,8 @@
 var Test =
 /*#__PURE__*/
 function (_Foo) {
+  "use strict";
+
   babelHelpers.inheritsLoose(Test, _Foo);
 
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packages/babel-plugin-transform-classes/test/fixtures/loose/constructor-order/output.js

@@ -1,6 +1,8 @@
 var x =
 /*#__PURE__*/
 function () {
+  "use strict";
+
   var _proto = x.prototype;
 
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packages/babel-plugin-transform-classes/test/fixtures/loose/derived-constructor-must-call-super/output.js

@@ -1,6 +1,8 @@
 var Foo =
 /*#__PURE__*/
 function (_Bar) {
+  "use strict";
+
   babelHelpers.inheritsLoose(Foo, _Bar);
 
   function Foo() {

packages/babel-plugin-transform-classes/test/fixtures/loose/derived-constructor-no-super-return-falsey/output.js

@@ -1,6 +1,8 @@
 var Child =
 /*#__PURE__*/
 function (_Base) {
+  "use strict";
+
   babelHelpers.inheritsLoose(Child, _Base);
 
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packages/babel-plugin-transform-classes/test/fixtures/loose/derived-constructor-no-super-return-object/output.js

@@ -1,6 +1,8 @@
 var Child =
 /*#__PURE__*/
 function (_Base) {
+  "use strict";
+
   babelHelpers.inheritsLoose(Child, _Base);
 
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packages/babel-plugin-transform-classes/test/fixtures/loose/literal-key/output.js

@@ -1,6 +1,8 @@
 var Foo =
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+  "use strict";
+
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   var _proto = Foo.prototype;

packages/babel-plugin-transform-classes/test/fixtures/loose/method-return-type-annotation/output.js

@@ -2,6 +2,8 @@
 var C =
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+  "use strict";
+
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packages/babel-plugin-transform-classes/test/fixtures/loose/method-reuse-prototype/output.js

@@ -1,6 +1,8 @@
 var Test =
 /*#__PURE__*/
 function () {
+  "use strict";
+
   function Test() {}
 
   var _proto = Test.prototype;

packages/babel-plugin-transform-classes/test/fixtures/loose/program-with-use-strict-directive/input.js

@@ -0,0 +1,7 @@
+"use strict";
+
+class Foo {
+    method() {
+        
+    }
+}

packages/babel-plugin-transform-classes/test/fixtures/loose/program-with-use-strict-directive/output.js

@@ -0,0 +1,13 @@
+"use strict";
+
+var Foo =
+/*#__PURE__*/
+function () {
+  function Foo() {}
+
+  var _proto = Foo.prototype;
+
+  _proto.method = function method() {};
+
+  return Foo;
+}();

packages/babel-plugin-transform-classes/test/fixtures/loose/super-class-id-member-expression/output.js

@@ -1,6 +1,8 @@
 var BaseController =
 /*#__PURE__*/
 function (_Chaplin$Controller) {
+  "use strict";
+
   babelHelpers.inheritsLoose(BaseController, _Chaplin$Controller);
 
   function BaseController() {
@@ -13,6 +15,8 @@ function (_Chaplin$Controller) {
 var BaseController2 =
 /*#__PURE__*/
 function (_Chaplin$Controller$A) {
+  "use strict";
+
   babelHelpers.inheritsLoose(BaseController2, _Chaplin$Controller$A);
 
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packages/babel-plugin-transform-classes/test/fixtures/loose/super-class/output.js

@@ -1,6 +1,8 @@
 var Test =
 /*#__PURE__*/
 function (_Foo) {
+  "use strict";
+
   babelHelpers.inheritsLoose(Test, _Foo);
 
   function Test() {

packages/babel-plugin-transform-classes/test/fixtures/loose/super-function-fallback/output.js

@@ -1,3 +1,5 @@
 var Test = function Test() {
+  "use strict";
+
   Function.prototype.hasOwnProperty.call(this, "test");
 };

packages/babel-plugin-transform-classes/test/fixtures/regression/5817/output.js

@@ -1,6 +1,8 @@
 var A =
 /*#__PURE__*/
 function (_B) {
+  "use strict";
+
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packages/babel-plugin-transform-classes/test/fixtures/regression/T2494/output.js

@@ -2,6 +2,8 @@ var x = {
   Foo:
   /*#__PURE__*/
   function (_Foo) {
+    "use strict";
+
     babelHelpers.inherits(_class, _Foo);
 
     function _class() {

packages/babel-plugin-transform-classes/test/fixtures/regression/T2997/output.js

@@ -1,10 +1,14 @@
 var A = function A() {
+  "use strict";
+
   babelHelpers.classCallCheck(this, A);
 };
 
 var B =
 /*#__PURE__*/
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+  "use strict";
+
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packages/babel-plugin-transform-classes/test/fixtures/regression/T6712/output.js

@@ -1,6 +1,8 @@
 var A =
 /*#__PURE__*/
 function () {
+  "use strict";
+
   function A() {
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packages/babel-plugin-transform-classes/test/fixtures/regression/T6755/output.js

@@ -1,6 +1,8 @@
 var Example =
 /*#__PURE__*/
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+  "use strict";
+
   function Example() {}
 
   var _proto = Example.prototype;

packages/babel-plugin-transform-classes/test/fixtures/regression/T7010/output.js

@@ -1,6 +1,8 @@
 var Foo =
 /*#__PURE__*/
 function () {
+  "use strict";
+
   function Foo(val) {
     babelHelpers.classCallCheck(this, Foo);
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packages/babel-plugin-transform-classes/test/fixtures/regression/T7537/output.js

@@ -15,12 +15,16 @@ function _instanceof(left, right) { if (right != null && typeof Symbol !== "unde
 function _classCallCheck(instance, Constructor) { if (!_instanceof(instance, Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
 
 var B = function B() {
+  "use strict";
+
   _classCallCheck(this, B);
 };
 
 var A =
 /*#__PURE__*/
 function (_B) {
+  "use strict";
+
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packages/babel-plugin-transform-classes/test/fixtures/spec/accessing-super-class/output.js

@@ -1,6 +1,8 @@
 var Test =
 /*#__PURE__*/
 function (_Foo) {
+  "use strict";
+
   babelHelpers.inherits(Test, _Foo);
 
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packages/babel-plugin-transform-classes/test/fixtures/spec/accessing-super-properties/output.js

@@ -1,6 +1,8 @@
 var Test =
 /*#__PURE__*/
 function (_Foo) {
+  "use strict";
+
   babelHelpers.inherits(Test, _Foo);
 
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packages/babel-plugin-transform-classes/test/fixtures/spec/calling-super-properties/output.js

@@ -1,6 +1,8 @@
 var Test =
 /*#__PURE__*/
 function (_Foo) {
+  "use strict";
+
   babelHelpers.inherits(Test, _Foo);
 
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packages/babel-plugin-transform-classes/test/fixtures/spec/computed-methods/output.js

@@ -1,6 +1,8 @@
 var Foo =
 /*#__PURE__*/
 function () {
+  "use strict";
+
   function Foo() {
     babelHelpers.classCallCheck(this, Foo);
   }

packages/babel-plugin-transform-classes/test/fixtures/spec/constructor-binding-collision/output.js

@@ -1,4 +1,6 @@
 var Example = function Example() {
+  "use strict";
+
   babelHelpers.classCallCheck(this, Example);
 
   var _Example;

packages/babel-plugin-transform-classes/test/fixtures/spec/constructor-only/input.js

@@ -0,0 +1,5 @@
+class Foo {
+    constructor() {
+
+    }
+}

packages/babel-plugin-transform-classes/test/fixtures/spec/constructor-only/output.js

@@ -0,0 +1,5 @@
+var Foo = function Foo() {
+  "use strict";
+
+  babelHelpers.classCallCheck(this, Foo);
+};

packages/babel-plugin-transform-classes/test/fixtures/spec/constructor/output.js

@@ -1,4 +1,6 @@
 var Test = function Test() {
+  "use strict";
+
   babelHelpers.classCallCheck(this, Test);
   this.state = "test";
 };
@@ -6,6 +8,8 @@ var Test = function Test() {
 var Foo =
 /*#__PURE__*/
 function (_Bar) {
+  "use strict";
+
   babelHelpers.inherits(Foo, _Bar);
 
   function Foo() {
@@ -21,6 +25,8 @@ function (_Bar) {
 }(Bar);
 
 var ConstructorScoping = function ConstructorScoping() {
+  "use strict";
+
   babelHelpers.classCallCheck(this, ConstructorScoping);
   var bar;
   {

packages/babel-plugin-transform-classes/test/fixtures/spec/delay-arrow-function-for-bare-super-derived/output.js

@@ -1,6 +1,8 @@
 var Foo =
 /*#__PURE__*/
 function (_Bar) {
+  "use strict";
+
   babelHelpers.inherits(Foo, _Bar);
 
   function Foo() {

packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-must-call-super-2/output.js

@@ -1,6 +1,8 @@
 var Foo =
 /*#__PURE__*/
 function (_Bar) {
+  "use strict";
+
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packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-must-call-super-3/output.js

@@ -1,6 +1,8 @@
 var Foo =
 /*#__PURE__*/
 function (_Bar) {
+  "use strict";
+
   babelHelpers.inherits(Foo, _Bar);
 
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packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-must-call-super-4/output.js

@@ -1,6 +1,8 @@
 var Foo =
 /*#__PURE__*/
 function (_Bar) {
+  "use strict";
+
   babelHelpers.inherits(Foo, _Bar);
 
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packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-must-call-super/output.js

@@ -1,6 +1,8 @@
 var Foo =
 /*#__PURE__*/
 function (_Bar) {
+  "use strict";
+
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packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-no-super-return-falsey/output.js

@@ -1,6 +1,8 @@
 var Child =
 /*#__PURE__*/
 function (_Base) {
+  "use strict";
+
   babelHelpers.inherits(Child, _Base);
 
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packages/babel-plugin-transform-classes/test/fixtures/spec/derived-constructor-no-super-return-object/output.js

@@ -1,6 +1,8 @@
 var Child =
 /*#__PURE__*/
 function (_Base) {
+  "use strict";
+
   babelHelpers.inherits(Child, _Base);
 
   function Child() {

packages/babel-plugin-transform-classes/test/fixtures/spec/inferred-expression-name/output.js

@@ -1,5 +1,7 @@
 var o = {
   foo: function foo() {
+    "use strict";
+
     babelHelpers.classCallCheck(this, foo);
   }
 };

packages/babel-plugin-transform-classes/test/fixtures/spec/instance-getter-and-setter/output.js

@@ -1,6 +1,8 @@
 var Test =
 /*#__PURE__*/
 function () {
+  "use strict";
+
   function Test() {
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packages/babel-plugin-transform-classes/test/fixtures/spec/instance-getter/output.js

@@ -1,6 +1,8 @@
 var Test =
 /*#__PURE__*/
 function () {
+  "use strict";
+
   function Test() {
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   }

packages/babel-plugin-transform-classes/test/fixtures/spec/instance-method/output.js

@@ -1,6 +1,8 @@
 var Test =
 /*#__PURE__*/
 function () {
+  "use strict";
+
   function Test() {
     babelHelpers.classCallCheck(this, Test);
   }

packages/babel-plugin-transform-classes/test/fixtures/spec/instance-setter/output.js

@@ -1,6 +1,8 @@
 var Test =
 /*#__PURE__*/
 function () {
+  "use strict";
+
   function Test() {
     babelHelpers.classCallCheck(this, Test);
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packages/babel-plugin-transform-classes/test/fixtures/spec/method-return-type-annotation/output.js

@@ -2,6 +2,8 @@
 var C =
 /*#__PURE__*/
 function () {
+  "use strict";
+
   function C() {
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   }

packages/babel-plugin-transform-classes/test/fixtures/spec/plain-class/output.js

@@ -1,3 +1,5 @@
 var Test = function Test() {
+  "use strict";
+
   babelHelpers.classCallCheck(this, Test);
 };

packages/babel-plugin-transform-classes/test/fixtures/spec/preserves-directives/output.js

@@ -1,5 +1,6 @@
 var MyCtrl = function MyCtrl(a) {
   "any directive prologue";
+  "use strict";
 
   babelHelpers.classCallCheck(this, MyCtrl);
   foo;
@@ -8,6 +9,7 @@ var MyCtrl = function MyCtrl(a) {
 var MyCtrl2 = function MyCtrl2(a) {
   "a";
   "b";
+  "use strict";
 
   babelHelpers.classCallCheck(this, MyCtrl2);
   foo;
@@ -15,6 +17,7 @@ var MyCtrl2 = function MyCtrl2(a) {
 
 var MyCtrl3 = function MyCtrl3(a) {
   "a";
+  "use strict";
 
   babelHelpers.classCallCheck(this, MyCtrl3);
   foo;

packages/babel-plugin-transform-classes/test/fixtures/spec/relaxed-method-coercion/output.js

@@ -2,6 +2,8 @@
 var Foo =
 /*#__PURE__*/
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+  "use strict";
+
   function Foo() {
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packages/babel-plugin-transform-classes/test/fixtures/spec/statement/output.js

@@ -1,9 +1,13 @@
 var BaseView = function BaseView() {
+  "use strict";
+
   babelHelpers.classCallCheck(this, BaseView);
   this.autoRender = true;
 };
 
 var BaseView = function BaseView() {
+  "use strict";
+
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@@ -11,6 +15,8 @@ var BaseView = function BaseView() {
 var BaseView =
 /*#__PURE__*/
 function () {
+  "use strict";
+
   function BaseView() {
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packages/babel-plugin-transform-classes/test/fixtures/spec/static/output.js

@@ -1,6 +1,8 @@
 var A =
 /*#__PURE__*/
 function () {
+  "use strict";
+
   function A() {
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packages/babel-plugin-transform-classes/test/fixtures/spec/super-class-anonymous/output.js

@@ -1,6 +1,8 @@
 var TestEmpty =
 /*#__PURE__*/
 function (_ref) {
+  "use strict";
+
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   function TestEmpty() {
@@ -12,6 +14,8 @@ function (_ref) {
 }(
 /*#__PURE__*/
 function () {
+  "use strict";
+
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@@ -22,6 +26,8 @@ function () {
 var TestConstructorOnly =
 /*#__PURE__*/
 function (_ref2) {
+  "use strict";
+
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@@ -33,6 +39,8 @@ function (_ref2) {
 }(
 /*#__PURE__*/
 function () {
+  "use strict";
+
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 var TestMethodOnly =
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+
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 var BaseController =
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 function (_Chaplin$Controller) {
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packages/babel-plugin-transform-classes/test/fixtures/spec/super-class/output.js

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packages/babel-plugin-transform-classes/test/fixtures/spec/super-function-fallback/output.js

@@ -1,4 +1,6 @@
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+
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@@ -15,6 +15,8 @@ function _assertThisInitialized(self) { if (self === void 0) { throw new Referen
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