Limit the amount of recursively nested child arrays on an object.

truncate-nesting.ts

/**
 * Takes menu structure limits the number of levels of nesting.
 * @param menuItems
 * @param maxLevels
 * @param level
 */
export const truncateNesting = <T extends { children?: T[] }>(
  menuItems: T[],
  maxLevels: number,
  level = 1
): T[] => {
  return menuItems.map((item) => {
    if ("children" in item && item.children?.length) {
      if (level >= maxLevels) {
        const { children, ...itemWithoutChildren } = item;
        return itemWithoutChildren as T;
      }
      const children = truncateNesting(item.children, maxLevels, level + 1);
      return { ...item, children };
    }
    return item;
  });
};