babel-plugin-transform-object-enumerables/lib/index.js

Helps obtain an array of keys, values, and key/value pairs (what the spec calls “entries”) from an object, for the purposes of iteration or serialization

"use strict";

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

exports.default = function () {
  return {
    visitor: {
      CallExpression: function CallExpression(path) {
        if (path.get("callee").matchesPattern("Object.enumerableKeys")) {
          path.replaceWithSourceString(keysSource);
        } else if (path.get("callee").matchesPattern("Object.enumerableValues")) {
          path.replaceWithSourceString(valuesSource);
        } else if (path.get("callee").matchesPattern("Object.enumerableEntries")) {
          path.replaceWithSourceString(entriesSource);
        }
      }
    }
  };
};

var keysSource = "((o) => { var r = []; for (var k in o) { r.push(k) } return r; })";
var valuesSource = "((o) => { var r = []; for (var k in o) { r.push(o[k]) } return r; })";
var entriesSource = "((o) => { var r = []; for (var k in o) { r.push([k, o[k]]) } return r; })";