Function baseClone

lodash.js:2667–2741

* The base implementation of `_.clone` and `_.cloneDeep` which tracks * traversed objects. * * @private * @param {*} value The value to clone. * @param {boolean} bitmask The bitmask flags. * 1 - Deep clone * 2 - Flatten inherited properties * 4 - Clone symb

(value, bitmask, customizer, key, object, stack)

     * @returns {*} Returns the cloned value.
     */
    function baseClone(value, bitmask, customizer, key, object, stack) {
      var result,
          isDeep = bitmask & CLONE_DEEP_FLAG,
          isFlat = bitmask & CLONE_FLAT_FLAG,
          isFull = bitmask & CLONE_SYMBOLS_FLAG;

      if (customizer) {
        result = object ? customizer(value, key, object, stack) : customizer(value);
      }
      if (result !== undefined) {
        return result;
      }
      if (!isObject(value)) {
        return value;
      }
      var isArr = isArray(value);
      if (isArr) {
        result = initCloneArray(value);
        if (!isDeep) {
          return copyArray(value, result);
        }
      } else {
        var tag = getTag(value),
            isFunc = tag == funcTag || tag == genTag;

        if (isBuffer(value)) {
          return cloneBuffer(value, isDeep);
        }
        if (tag == objectTag || tag == argsTag || (isFunc && !object)) {
          result = (isFlat || isFunc) ? {} : initCloneObject(value);
          if (!isDeep) {
            return isFlat
              ? copySymbolsIn(value, baseAssignIn(result, value))
              : copySymbols(value, baseAssign(result, value));
          }
        } else {
          if (!cloneableTags[tag]) {
            return object ? value : {};
          }
          result = initCloneByTag(value, tag, isDeep);
        }
      }
      // Check for circular references and return its corresponding clone.
      stack || (stack = new Stack);
      var stacked = stack.get(value);
      if (stacked) {
        return stacked;
      }
      stack.set(value, result);

      if (isSet(value)) {
        value.forEach(function(subValue) {
          result.add(baseClone(subValue, bitmask, customizer, subValue, value, stack));
        });
      } else if (isMap(value)) {
        value.forEach(function(subValue, key) {
          result.set(key, baseClone(subValue, bitmask, customizer, key, value, stack));
        });