message: add error testing for if it's undefined
diff: * Removes all null entries.
  */
  export function filterNull<T> (obj: Record<string, T>) {
  + if (typeof obj === 'undefined') return
  const propNames = Object.getOwnPropertyNames(obj)
  for (let i = 0; i < propNames.length; i++) {
  const propName = propNames[i]
  