JavaScript Array - from flat to hierarchical

Question

In the array, if an element's item_parent === an element's item_id I want to add it to that element as children;

so "Sr. Project Manager" ends up a child of "General Conditions" and "General Conditions" ends up a child of "General Stuff"...

[
  {
    "cost_code": "007202",
    "item_id": "15531666136289",
    "item_parent": "15531666136277",
    "name": "Sr. Project Manager"
  },
  {
    "cost_code": "007200",
    "item_id": "15531666136277",
    "item_parent": "15531666136241",
    "name": "General Conditions"
  },
  {
    "cost_code": "000000",
    "item_id": "15531666136241",
    "item_parent": "0",
    "name": "General Stuff"
  }
]