code: function normalizeWatchItem(value) {
      let handlers;
      let options = {};
      let valueType = typeof value;
      if (valueType === 'function' || valueType === 'string') {
          handlers = [value];
      }
      else if (Array.isArray(value)) {
          handlers = value;
      }
      else {
          handlers = [value.handler];
          options.immediate = value.immediate;
      }
  
      let watchHandler = function (...args) {
          for (let i = 0, len = handlers.length; i < len; i++) {
              let item = handlers[i];
              if (typeof item === 'string') {
                  item = this[item];
              }
              item.apply(this, args);
          }
      };
  
      return {
          handler: watchHandler,
          options
      };
  }
docs: /* eslint-disable fecs-camelcase 
  Normalize watch info
  
  @inner
  @param {*} value the watch info to normalize
  @return {Object}