Find parent and child from array javascript

var data = [{ depth: 0, id: "f35vz2f" }, { depth: 0, id: "f359354" }, { depth: 1, id: "f35e0b0", parent_id: "f359354" }, { depth: 2, id: "f35ji24", parent_id: "f35e0b0" }, { depth: 2, id: "f35rnwb", parent_id: "" }, { depth: 2, id: "f35ojh4", parent_id: "f35e0b0" }, { depth: 3, id: "f35lmch", parent_id: "f35ji24" }, { depth: 3, id: "f35kl96", parent_id: "f35ji24" }],
    tree = function (data, root) {
        var t = {};
        data.forEach(o => {
            Object.assign(t[o.id] = t[o.id] || {}, o);
            t[o.parent_id] = t[o.parent_id] || {};
            t[o.parent_id].children = t[o.parent_id].children || [];
            t[o.parent_id].children.push(t[o.id]);
        });
        return t[root].children;
    }(data, undefined);

console.log(tree);