Function visit

packages/react-stately/src/table/useTreeGridState.ts:174–193

(node: GridNode<T>)

  let topLevelRows: GridNode<T>[] = [];
  let visit = (node: GridNode<T>) => {
    switch (node.type) {
      case 'body':
        body = node;
        keyMap.set(body.key, body);
        break;
      case 'column':
        if (!node.hasChildNodes) {
          userColumnCount++;
        }
        break;
      case 'item':
        topLevelRows.push(node);
        return;
    }

    for (let child of node.childNodes) {
      visit(child);
    }
  };

  for (let node of nodes) {
    if (node.type === 'column') {