A javascript function to get string of array and return a tree of data

tree.js

/**
 *
 * @param {Array} arr of strings provided for each Prodct listing / search page by aloglia
 * @returns {Array} Modified array of nested objects in a tree structure for each category
 */

export const getTreeData = arr => {
  let mapper = {}
  let root = {
    children: []
  }

  /**
   * Map over incoming array of string and create parent child tree structure for each provided category
   */

  for (const str of arr) {
    let splits = str.split('>'),
      path = ''

    splits.reduce((parent, id, i) => {
      //preserve the original filter key for algolia
      i === splits.length - 1 ? (path += `${id}`) : (path += `${id}>`)
      if (!mapper[path]) {
        let name = id
        name = name.trim() // clean any kind of white space as a result of split in the previous step
        const obj = {
          id: id,
          label: name,
          value: path
        }
        mapper[path] = obj // set the new object with unique path
        parent.children = parent.children || [] //set to empty array in case child not applicable
        parent.children.push(obj)
      }

      return mapper[path]
    }, root)
  }

  return root.children
}