Implementing 'getElementsByClassName' from scratch in JavaScript

getElementsByClassName.js

function getElementsByClassName2(className) {
  const nodes = []
  
  function crawl(node) {
    if (node.classList && node.classList.value.indexOf(className) > -1) {
      nodes.push(node)
    }
    node.childNodes.forEach((child) => 
      crawl(child)
    )
  }
  crawl(document.body)
  
  return nodes
}