Split CSV

splitCSV.js

function splitCsv(str) {
  return str.split(',').reduce((accum,curr)=>{
    if(accum.isConcatting) {
      accum.soFar[accum.soFar.length-1] += ','+curr
    } else {
      accum.soFar.push(curr)
    }
    if(curr.split('"').length % 2 == 0) {
      accum.isConcatting= !accum.isConcatting
    }
    return accum;
  },{soFar:[],isConcatting:false}).soFar
}

console.log(splitCsv('asdf,"a,d",fdsa'),' should be ',['asdf','"a,d"','fdsa'])
console.log(splitCsv(',asdf,,fds,'),' should be ',['','asdf','','fds',''])
console.log(splitCsv('asdf,"a,,,d",fdsa'),' should be ',['asdf','"a,,,d"','fdsa'])