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"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = deepCyclicCopy;
/**
 * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */

const EMPTY = new Set();
function deepCyclicCopy(value, options = {
  blacklist: EMPTY,
  keepPrototype: false
}, cycles = new WeakMap()) {
  if (typeof value !== 'object' || value === null || Buffer.isBuffer(value)) {
    return value;
  } else if (cycles.has(value)) {
    return cycles.get(value);
  } else if (Array.isArray(value)) {
    return deepCyclicCopyArray(value, options, cycles);
  } else {
    return deepCyclicCopyObject(value, options, cycles);
  }
}
function deepCyclicCopyObject(object, options, cycles) {
  const newObject = options.keepPrototype ? Object.create(Object.getPrototypeOf(object)) : {};
  const descriptors = Object.getOwnPropertyDescriptors(object);
  cycles.set(object, newObject);
  Object.keys(descriptors).forEach(key => {
    if (options.blacklist && options.blacklist.has(key)) {
      delete descriptors[key];
      return;
    }
    const descriptor = descriptors[key];
    if (typeof descriptor.value !== 'undefined') {
      descriptor.value = deepCyclicCopy(descriptor.value, {
        blacklist: EMPTY,
        keepPrototype: options.keepPrototype
      }, cycles);
    }
    descriptor.configurable = true;
  });
  return Object.defineProperties(newObject, descriptors);
}
function deepCyclicCopyArray(array, options, cycles) {
  const newArray = options.keepPrototype ? new (Object.getPrototypeOf(array).constructor)(array.length) : [];
  const length = array.length;
  cycles.set(array, newArray);
  for (let i = 0; i < length; i++) {
    newArray[i] = deepCyclicCopy(array[i], {
      blacklist: EMPTY,
      keepPrototype: options.keepPrototype
    }, cycles);
  }
  return newArray;
}