Found an issue of the util.js

[codTango]

Hey, I just found that there's an issue for the util. The scenario is that I have multiple trees like this:

[
  {
    "label": "A",
    "value": "1",
    "key": "1",
    "parentId": null,
    "isLeaf": false,
    "children": [
      {
        "label": "A1",
        "value": "2",
        "key": "2",
        "parentId": "1",
        "isLeaf": true
      },
      {
        "label": "A2",
        "value": "3",
        "key": "3",
        "parentId": "1",
        "isLeaf": true
      }
    ]
  },
  {
    "label": "B",
    "value": "4",
    "key": "4",
    "parentId": null,
    "isLeaf": false,
    "children": [
      {
        "label": "BB",
        "value": "5",
        "key": "5",
        "parentId": "4",
        "isLeaf": true
      }
    ]
  },
  {
    "label": "C",
    "value": "8",
    "key": "8",
    "parentId": null,
    "isLeaf": false,
    "children": [
      {
        "label": "CC",
        "value": "9",
        "key": "9",
        "parentId": "8",
        "isLeaf": true
      }
    ]
  }
]

In filterAllCheckedData function, when I select all the root nodes (A B C), and then select some of their children nodes, this checking will push an object with some undefined properties to checkedNodesPositions.

    if (siblingChecked === len) {
      parent.__checked = true;
      checkedNodesPositions.push({ node: parent, pos: parent._pos });

Later, it will throw errors on trying to split on the undefined property within flatToHierarchy function.

[codTango]

one workaround I'm thinking is that append the multiple trees to a root, and then make the root node invisible, but not sure how to make a tree node invisible.