packages/node_modules/pouchdb-utils/src/clone.js

import isBinaryObject from './isBinaryObject';
import cloneBinaryObject from './cloneBinaryObject';
import isPlainObject from './isPlainObject';

function clone(object) {
  var newObject;
  var i;
  var len;

  if (!object || typeof object !== 'object') {
    return object;
  }

  if (Array.isArray(object)) {
    newObject = [];
    for (i = 0, len = object.length; i < len; i++) {
      newObject[i] = clone(object[i]);
    }
    return newObject;
  }

  // special case: to avoid inconsistencies between IndexedDB
  // and other backends, we automatically stringify Dates
  if (object instanceof Date && isFinite(object)) {
    return object.toISOString();
  }

  if (isBinaryObject(object)) {
    return cloneBinaryObject(object);
  }

  if (!isPlainObject(object)) {
    return object; // don't clone objects like Workers
  }

  newObject = {};
  for (i in object) {
    /* istanbul ignore else */
    if (Object.prototype.hasOwnProperty.call(object, i) && i !== '__proto__') {
      var value = clone(object[i]);
      if (typeof value !== 'undefined') {
        newObject[i] = value;
        Object.defineProperty(newObject, i, {
          value, writable: true, enumerable: true, configurable: true
        });
      }
    }
  }
  return newObject;
}

export default clone;