`Breadth-first search` algorithm for Binary Search Tree

Breadth First Search.js

//breadth_First_Search
//This method, visits tree's node horizontally and pushes them. It uses queue to keep track of its work.
//Example:   10
//      6          15
//   3    8            20

//result node would be =[10, 6, 15, 3, 8, 20]


//The Breadth-first search algorithm that's shown in here, is for data structures like `Binary Search Tree`.

const breadth_First_Search = tree => {
  let node = tree.root;
  let queue = [];
  let visited = [];
  queue.push(node);
  while (queue.length) {
    node = queue.shift();
    visited.push(node.value);
    if (node.left) queue.push(node.left);
    if (node.right) queue.push(node.right);
  }
  return visited;
};




//EXAMPLE===================================================================
const exampleBST = {
  "root": {
    "value": 10,
    "right": {
      "value": 15,
      "right": {
        "value": 20,
        "right": null,
        "left": null
      },
      "left": null
    },
    "left": {
      "value": 6,
      "right": {
        "value": 8,
        "right": null,
        "left": null
      },
      "left": {
        "value": 3,
        "right": null,
        "left": null
      }
    }
  }
}

const totalNode = breadth_First_Search(exampleBST); //returns [10, 6, 15, 3, 8, 20]