A pair of tools allowing to pick a set of properties from object or get an object without passed list of properties

pick-omit.js

const match = (fields, key) => {
  if (["string", "number"].indexOf(typeof fields) !== -1) return fields === key
  if (fields.indexOf) return fields.indexOf(key) !== -1

  return false
}

const omit = (obj, fields) => Object.keys(obj).reduce((accum, propName) => {
  if (match(fields, propName)) return accum
  return { ...accum, [propName]: obj[propName] }
}, {})

const pick = (obj, fields) => Object.keys(obj).reduce((accum, propName) => {
  if (match(fields, propName)) return { ...accum, [propName]: obj[propName] }
  return accum
}, {})