code: function mergeHelper(base, mixin, name, mergeArrays) {
      if (Array.isArray(mixin[name])) {
          if (!mergeArrays && base[name] && Array.isArray(base[name])) {
              base[name] = base[name].concat(mixin[name]);
          } else {
              base[name] = mixin[name];
          }
      } else if (typeof mixin[name] === 'object' && mixin[name] !== null) {
          let newBase = base[name] || {};
          if (Array.isArray(newBase)) {
              newBase = {};
          }
          mergeInner(newBase, mixin[name], mergeArrays);
          base[name] = newBase;
      } else {
          base[name] = mixin[name];
      }
  }
docs: Merge helper - FOR INTERNAL USE ONLY
  
  @param {object} base Base object to merge `mixin` into
  @param {object} mixin Mixin object to merge into `base`
  @param {string} name Name of property to merge
  @param {boolean} [mergeArrays] Merge arrays instead of concatenating them