array object to tree

tree.js

const nodeList = [
    {"id":1,"parentId":0,"name":"AA"},
    {"id":2,"parentId":1,"name":"BB"},
    {"id":3,"parentId":1,"name":"CC"},
    {"id":4,"parentId":3,"name":"DD"},
    {"id":5,"parentId":3,"name":"EE"},
    {"id":6,"parentId":2,"name":"FF"},
    {"id":7,"parentId":2,"name":"GG"},
    {"id":8,"parentId":4,"name":"HH"},
    {"id":9,"parentId":5,"name":"II"}
];


nodeList.forEach(n1 => {
    nodeList.forEach(n2 => {
        if (n2.id == n1.parentId) {
           if (!n2.childNodes) n2.childNodes = [];
           n2.childNodes.push(n1);
        }
    });
});

nodeList.sort((f,s) => f.parentId - s.parentId);

const tabStr = '  ';
console.log(nodeList[0].name);
const printNode = function(n, index) {
    if (n.childNodes) {
      n.childNodes.forEach((nn, i) => {
         console.log(tabStr.repeat(index) + nn.name);
         if (nn.childNodes && nn.childNodes.length > 0) {
            printNode(nn, index+1);
         }
      }); 
    }
}
printNode(nodeList[0], 1)