babel-plugin-transform-builtin-classes/lib/index.js

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'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});

var _symbol = require('babel-runtime/core-js/symbol');

var _symbol2 = _interopRequireDefault(_symbol);

exports.default = function (babel) {

  var name = void 0;

  var VISITED = (0, _symbol2.default)();
  var t = babel.types;


  var needsWrapping = function needsWrapping(path, globals) {
    var superClass = path.get('superClass');
    return !!superClass.node && (globals || []).some(function (name) {
      return superClass.isIdentifier({ name: name });
    });
  };

  var getName = function getName(path) {
    if (!name) {
      name = path.scope.generateUidIdentifier('fixBabelExtend');
      path.scope.getProgramParent().path.unshiftContainer('body', fixAsTemplate({ HELPER: name }));
    }
    return name;
  };

  return {
    pre: function pre() {
      name = null;
    },

    visitor: {
      ClassDeclaration: function ClassDeclaration(path) {
        var node = path.node;

        if (!node[VISITED] && needsWrapping(path, this.opts.globals)) {
          var _name = getName(path);
          var ref = node.id || path.scope.generateUidIdentifier('class');
          path.replaceWith(t.variableDeclaration('let', [t.variableDeclarator(ref, t.callExpression(_name, [t.toExpression(node)]))]));
        }
        node[VISITED] = true;
      },
      ClassExpression: function ClassExpression(path) {
        var node = path.node;

        if (!node[VISITED] && needsWrapping(path, this.opts.globals)) {
          var _name2 = getName(path);
          path.replaceWith(t.callExpression(_name2, [t.toExpression(node)]));
        }
        node[VISITED] = true;
      }
    },
    post: function post() {
      if (name && this.opts.logIfPatched) console.warn(' ✔ builtin extends patched');
    }
  };
};

var _babelTemplate = require('babel-template');

var _babelTemplate2 = _interopRequireDefault(_babelTemplate);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

var fixAsTemplate = (0, _babelTemplate2.default)('\nvar HELPER = (function (O) {\n  var\n    gPO = O.getPrototypeOf || function (o) { return o.__proto__; },\n    sPO = O.setPrototypeOf || function (o, p) { o.__proto__ = p; return o; },\n    construct = typeof Reflect === \'object\' ?\n      Reflect.construct :\n      function (Parent, args, Class) {\n        var Constructor, a = [null];\n        a.push.apply(a, args);\n        Constructor = Parent.bind.apply(Parent, a);\n        return sPO(new Constructor, Class.prototype);\n      }\n  ;\n  return function fixBabelExtend(Class) {\n    var Parent = gPO(Class);\n    return sPO(\n      Class,\n      sPO(\n        function Super() {\n          return construct(Parent, arguments, gPO(this).constructor);\n        },\n        Parent\n      )\n    );\n  };\n}(Object));\n');