Split Chunk Array in JavaScript

chunk.js

//specs
chunk([1,2,3,4], 2) // [[1,2][3,4]]
chunk([1,2,3,4,5], 2) // [[1,2],[3,4],[5]]
chunk([1,2,3,4,5], 10) // [[1,2,3,4,5]]

//solution 1
function chunk(array, size) {

  const chunked = [];

  for (let elem of array) {
    const last = chunked[chunked.length - 1];
    if (!last || last.length === size) {
      chunked.push([elem]);
    } else {
      last.push(elem);
    }
  }
  return chunked;
}

//solution 2
function chunk(array, size) {
  const chunked = [];
  let index = 0;
  while(index < array.length) {
    chunked.push(array.slice(index, index + size));
    index += size;
  }
  return chunked;
}