Memoize computed super properties (#7776)

Fixes #7775.

packages/babel-plugin-transform-classes/test/fixtures/get-set/memoized-assign/exec.js

@@ -0,0 +1,41 @@
+"use strict";
+class Base {}
+Object.defineProperty(Base.prototype, 0, {
+  value: 0,
+  writable: true,
+  configurable: true,
+});
+Object.defineProperty(Base.prototype, 1, {
+  value: 1,
+  writable: true,
+  configurable: true,
+});
+
+let i = 0;
+const proper = {
+  get prop() {
+    return i++;
+  },
+};
+
+class Obj extends Base {
+  assign() {
+    super[proper.prop] += 1;
+  }
+
+  assign2() {
+    super[i] += 1;
+  }
+}
+
+const obj = new Obj();
+
+obj.assign();
+expect(i).toBe(1);
+expect(obj[0]).toBe(1);
+expect(obj[1]).toBe(1);
+
+obj.assign2();
+expect(i).toBe(1);
+expect(obj[0]).toBe(1);
+expect(obj[1]).toBe(2);

packages/babel-plugin-transform-classes/test/fixtures/get-set/memoized-assign/input.js

@@ -0,0 +1,41 @@
+"use strict";
+class Base {}
+Object.defineProperty(Base.prototype, 0, {
+  value: 0,
+  writable: true,
+  configurable: true,
+});
+Object.defineProperty(Base.prototype, 1, {
+  value: 1,
+  writable: true,
+  configurable: true,
+});
+
+let i = 0;
+const proper = {
+  get prop() {
+    return i++;
+  },
+};
+
+class Obj extends Base {
+  assign() {
+    super[proper.prop] += 1;
+  }
+
+  assign2() {
+    super[i] += 1;
+  }
+}
+
+const obj = new Obj();
+
+obj.assign();
+expect(i).toBe(1);
+expect(obj[0]).toBe(1);
+expect(obj[1]).toBe(1);
+
+obj.assign2();
+expect(i).toBe(1);
+expect(obj[0]).toBe(1);
+expect(obj[1]).toBe(2);

packages/babel-plugin-transform-classes/test/fixtures/get-set/memoized-assign/output.js

@@ -0,0 +1,89 @@
+"use strict";
+
+function _defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } }
+
+function _createClass(Constructor, protoProps, staticProps) { if (protoProps) _defineProperties(Constructor.prototype, protoProps); if (staticProps) _defineProperties(Constructor, staticProps); return Constructor; }
+
+function _possibleConstructorReturn(self, call) { if (call && (typeof call === "object" || typeof call === "function")) { return call; } return _assertThisInitialized(self); }
+
+function _assertThisInitialized(self) { if (self === void 0) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return self; }
+
+function set(target, property, value, receiver) { if (typeof Reflect !== "undefined" && Reflect.set) { set = Reflect.set; } else { set = function set(target, property, value, receiver) { var base = _superPropBase(target, property); var desc; if (base) { desc = Object.getOwnPropertyDescriptor(base, property); if (desc.set) { desc.set.call(receiver, value); return true; } else if (!desc.writable) { return false; } } desc = Object.getOwnPropertyDescriptor(receiver, property); if (desc) { if (!desc.writable) { return false; } desc.value = value; Object.defineProperty(receiver, property, desc); } else { _defineProperty(receiver, property, value); } return true; }; } return set(target, property, value, receiver); }
+
+function _set(target, property, value, receiver, isStrict) { const s = set(target, property, value, receiver || target); if (!s && isStrict) { throw new Error('failed to set property'); } return value; }
+
+function _defineProperty(obj, key, value) { if (key in obj) { Object.defineProperty(obj, key, { value: value, enumerable: true, configurable: true, writable: true }); } else { obj[key] = value; } return obj; }
+
+function _get(target, property, receiver) { if (typeof Reflect !== "undefined" && Reflect.get) { _get = Reflect.get; } else { _get = function _get(target, property, receiver) { var base = _superPropBase(target, property); if (!base) return; var desc = Object.getOwnPropertyDescriptor(base, property); if (desc.get) { return desc.get.call(receiver); } return desc.value; }; } return _get(target, property, receiver || target); }
+
+function _superPropBase(object, property) { while (!Object.prototype.hasOwnProperty.call(object, property)) { object = _getPrototypeOf(object); if (object === null) break; } return object; }
+
+function _getPrototypeOf(o) { _getPrototypeOf = Object.getPrototypeOf || function _getPrototypeOf(o) { return o.__proto__; }; return _getPrototypeOf(o); }
+
+function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function"); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) _setPrototypeOf(subClass, superClass); }
+
+function _setPrototypeOf(o, p) { _setPrototypeOf = Object.setPrototypeOf || function _setPrototypeOf(o, p) { o.__proto__ = p; return o; }; return _setPrototypeOf(o, p); }
+
+function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
+
+let Base = function Base() {
+  _classCallCheck(this, Base);
+};
+
+Object.defineProperty(Base.prototype, 0, {
+  value: 0,
+  writable: true,
+  configurable: true
+});
+Object.defineProperty(Base.prototype, 1, {
+  value: 1,
+  writable: true,
+  configurable: true
+});
+let i = 0;
+const proper = {
+  get prop() {
+    return i++;
+  }
+
+};
+
+let Obj =
+/*#__PURE__*/
+function (_Base) {
+  _inherits(Obj, _Base);
+
+  function Obj() {
+    _classCallCheck(this, Obj);
+
+    return _possibleConstructorReturn(this, _getPrototypeOf(Obj).apply(this, arguments));
+  }
+
+  _createClass(Obj, [{
+    key: "assign",
+    value: function assign() {
+      var _proper$prop;
+
+      _set(_getPrototypeOf(Obj.prototype), _proper$prop = proper.prop, _get(_getPrototypeOf(Obj.prototype), _proper$prop, this) + 1, this, true);
+    }
+  }, {
+    key: "assign2",
+    value: function assign2() {
+      var _i;
+
+      _set(_getPrototypeOf(Obj.prototype), _i = i, _get(_getPrototypeOf(Obj.prototype), _i, this) + 1, this, true);
+    }
+  }]);
+
+  return Obj;
+}(Base);
+
+const obj = new Obj();
+obj.assign();
+expect(i).toBe(1);
+expect(obj[0]).toBe(1);
+expect(obj[1]).toBe(1);
+obj.assign2();
+expect(i).toBe(1);
+expect(obj[0]).toBe(1);
+expect(obj[1]).toBe(2);

packages/babel-plugin-transform-classes/test/fixtures/get-set/memoized-update/exec.js

@@ -0,0 +1,41 @@
+"use strict";
+class Base {}
+Object.defineProperty(Base.prototype, 0, {
+  value: 0,
+  writable: true,
+  configurable: true,
+});
+Object.defineProperty(Base.prototype, 1, {
+  value: 1,
+  writable: true,
+  configurable: true,
+});
+
+let i = 0;
+const proper = {
+  get prop() {
+    return i++;
+  },
+};
+
+class Obj extends Base {
+  update() {
+    super[proper.prop]++;
+  }
+
+  update2() {
+    super[i]++;
+  }
+}
+
+const obj = new Obj();
+
+obj.update();
+expect(i).toBe(1);
+expect(obj[0]).toBe(1);
+expect(obj[1]).toBe(1);
+
+obj.update2();
+expect(i).toBe(1);
+expect(obj[0]).toBe(1);
+expect(obj[1]).toBe(2);

packages/babel-plugin-transform-classes/test/fixtures/get-set/memoized-update/input.js

@@ -0,0 +1,41 @@
+"use strict";
+class Base {}
+Object.defineProperty(Base.prototype, 0, {
+  value: 0,
+  writable: true,
+  configurable: true,
+});
+Object.defineProperty(Base.prototype, 1, {
+  value: 1,
+  writable: true,
+  configurable: true,
+});
+
+let i = 0;
+const proper = {
+  get prop() {
+    return i++;
+  },
+};
+
+class Obj extends Base {
+  update() {
+    super[proper.prop]++;
+  }
+
+  update2() {
+    super[i]++;
+  }
+}
+
+const obj = new Obj();
+
+obj.update();
+expect(i).toBe(1);
+expect(obj[0]).toBe(1);
+expect(obj[1]).toBe(1);
+
+obj.update2();
+expect(i).toBe(1);
+expect(obj[0]).toBe(1);
+expect(obj[1]).toBe(2);

packages/babel-plugin-transform-classes/test/fixtures/get-set/memoized-update/output.js

@@ -0,0 +1,89 @@
+"use strict";
+
+function _defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } }
+
+function _createClass(Constructor, protoProps, staticProps) { if (protoProps) _defineProperties(Constructor.prototype, protoProps); if (staticProps) _defineProperties(Constructor, staticProps); return Constructor; }
+
+function _possibleConstructorReturn(self, call) { if (call && (typeof call === "object" || typeof call === "function")) { return call; } return _assertThisInitialized(self); }
+
+function _assertThisInitialized(self) { if (self === void 0) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return self; }
+
+function set(target, property, value, receiver) { if (typeof Reflect !== "undefined" && Reflect.set) { set = Reflect.set; } else { set = function set(target, property, value, receiver) { var base = _superPropBase(target, property); var desc; if (base) { desc = Object.getOwnPropertyDescriptor(base, property); if (desc.set) { desc.set.call(receiver, value); return true; } else if (!desc.writable) { return false; } } desc = Object.getOwnPropertyDescriptor(receiver, property); if (desc) { if (!desc.writable) { return false; } desc.value = value; Object.defineProperty(receiver, property, desc); } else { _defineProperty(receiver, property, value); } return true; }; } return set(target, property, value, receiver); }
+
+function _set(target, property, value, receiver, isStrict) { const s = set(target, property, value, receiver || target); if (!s && isStrict) { throw new Error('failed to set property'); } return value; }
+
+function _defineProperty(obj, key, value) { if (key in obj) { Object.defineProperty(obj, key, { value: value, enumerable: true, configurable: true, writable: true }); } else { obj[key] = value; } return obj; }
+
+function _get(target, property, receiver) { if (typeof Reflect !== "undefined" && Reflect.get) { _get = Reflect.get; } else { _get = function _get(target, property, receiver) { var base = _superPropBase(target, property); if (!base) return; var desc = Object.getOwnPropertyDescriptor(base, property); if (desc.get) { return desc.get.call(receiver); } return desc.value; }; } return _get(target, property, receiver || target); }
+
+function _superPropBase(object, property) { while (!Object.prototype.hasOwnProperty.call(object, property)) { object = _getPrototypeOf(object); if (object === null) break; } return object; }
+
+function _getPrototypeOf(o) { _getPrototypeOf = Object.getPrototypeOf || function _getPrototypeOf(o) { return o.__proto__; }; return _getPrototypeOf(o); }
+
+function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function"); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) _setPrototypeOf(subClass, superClass); }
+
+function _setPrototypeOf(o, p) { _setPrototypeOf = Object.setPrototypeOf || function _setPrototypeOf(o, p) { o.__proto__ = p; return o; }; return _setPrototypeOf(o, p); }
+
+function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
+
+let Base = function Base() {
+  _classCallCheck(this, Base);
+};
+
+Object.defineProperty(Base.prototype, 0, {
+  value: 0,
+  writable: true,
+  configurable: true
+});
+Object.defineProperty(Base.prototype, 1, {
+  value: 1,
+  writable: true,
+  configurable: true
+});
+let i = 0;
+const proper = {
+  get prop() {
+    return i++;
+  }
+
+};
+
+let Obj =
+/*#__PURE__*/
+function (_Base) {
+  _inherits(Obj, _Base);
+
+  function Obj() {
+    _classCallCheck(this, Obj);
+
+    return _possibleConstructorReturn(this, _getPrototypeOf(Obj).apply(this, arguments));
+  }
+
+  _createClass(Obj, [{
+    key: "update",
+    value: function update() {
+      var _proper$prop, _super$proper$prop;
+
+      _set(_getPrototypeOf(Obj.prototype), _proper$prop = proper.prop, (_super$proper$prop = +_get(_getPrototypeOf(Obj.prototype), _proper$prop, this)) + 1, this, true), _super$proper$prop;
+    }
+  }, {
+    key: "update2",
+    value: function update2() {
+      var _i, _super$i;
+
+      _set(_getPrototypeOf(Obj.prototype), _i = i, (_super$i = +_get(_getPrototypeOf(Obj.prototype), _i, this)) + 1, this, true), _super$i;
+    }
+  }]);
+
+  return Obj;
+}(Base);
+
+const obj = new Obj();
+obj.update();
+expect(i).toBe(1);
+expect(obj[0]).toBe(1);
+expect(obj[1]).toBe(1);
+obj.update2();
+expect(i).toBe(1);
+expect(obj[0]).toBe(1);
+expect(obj[1]).toBe(2);