SOURCE

const data = [
  { province: "广东省", city: "广州市", district: "天河区" },
  { province: "广东省", city: "广州市", district: "白云区" },
  { province: "广东省", city: "东莞市", district: "石龙镇" },
]

function bbb(data, keys, keyVals = []) {
  let arr = []
  for (let i = 0; i < data.length; i++) {
    let index = 0
    for (let k = 0; k < keyVals.length; k++) {
      const key = keys[k]
      if (data[i][key] === keyVals[k]) {
        index = k + 1
      }
    }
    let test = data[i][keys[index]]
    if ((index == 0 || index == keyVals.length) && arr.findIndex((c) => c.name === data[i][keys[index]]) === -1) {
      let newKeyVals = [].concat(keyVals)
      newKeyVals.push(data[i][keys[index]])
      arr.push({
        name: data[i][keys[index]],
        children: keys.length === newKeyVals.length ? [] : bbb(data, keys, newKeyVals),
      })
    }
  }
  return arr
}

let cc = bbb(data, ["province", "city", "district"])
console.log(JSON.stringify(cc))