message: fixed filterNull
diff: /* for removing null entries */
  export function filterNull<T> (obj: Record<string, T>) {
  - return Object.keys(obj)
  - .filter(e => obj[e] !== null)
  - .reduce((o, e) => {
  - o[e] = obj[e]
  - return o
  - }, {})
  + const propNames = Object.getOwnPropertyNames(obj)
  + for (let i = 0; i < propNames.length; i++) {
  + const propName = propNames[i]
  + if (obj[propName] === null || obj[propName] === undefined) {
  + delete obj[propName]
  + }
  + }
  }
  