JSFiddle - React, Tailwind, and code Playground

JavaScript

var jsonData = [{
  "id": "1",
  "name": "test1",
  "sub_values": [{
    "id": "1",
    "name": "Test1",
    "sub_values": []
  }]
}, {
  "id": "2",
  "name": "test2",
  "sub_values": [{
    "id": "1",
    "name": "Test5",
    "sub_values": []
  }, {
    "id": "1",
    "name": "Test10",
    "sub_values": []
  }, {
    "id": "1",
    "name": "Test20",
    "sub_values": []
  }]
}, {
  "id": "3",
  "name": "test3",
  "sub_values": [{
    "id": "1",
    "name": "Test50",
    "sub_values": []
  }]
}];

for (var objectItem in jsonData) {
  var obj = jsonData[objectItem];
  if (obj.hasOwnProperty('sub_values')) {
    for (var subObj in obj.sub_values) {

      var subObject = obj.sub_values[subObj];
      console.log(subObject);

      for (var i = 0; i < subObject.sub_values.length; i++) {
        console.log(subObject.sub_values[i]);
      }
    }
  }
}