object filter

object-filter.js

export const objectFilter = ( obj, predicate ) => {
  if ( obj === null || obj === undefined )
    throw Error( 'Cannot convert null or undefined to an object' )

  if ( typeof predicate !== 'function' )
    throw Error( 'Expected predicate to be a function' )

  obj = Object( obj )

  return Object.keys( obj ).reduce(
    ( filtered, key ) => {
      if(
        Object.prototype.hasOwnProperty.call( obj, key ) &&
        predicate( obj[ key ], key, obj )
      ){
        filtered[ key ] = obj[ key ]
      }

      return filtered
    },
    {}
  )
}