Split an array into N number of chunks

splitEvery.js

export default ( chunkLength = 20 , sourceArray = [] ) => (

    sourceArray.reduce( (accumulated, current, index) => {
        let chunkN = Math.floor( index/chunkLength );
        accumulated[ chunkN ] = ( accumulated[ chunkN ]||[]).concat( current );
        return accumulated;
    }, [])

);