docs: function normalizeItems ({data, labelAttribute, records, valueAttribute}) {
    const labelAttr = labelAttribute || 'label'
    const valueAttr = valueAttribute || 'id'
  
    return data.concat(
      records.map((record) => {
        if (typeof record !== 'object') {
          return {
            label: `${record}`, // make sure label is a string
            value: record
          }
        }
  
        let label, value
  
        if (labelAttr.indexOf('${') !== -1) {
          label = utils.parseVariables(record, labelAttr)
        } else {
          label = get(record, labelAttr) || get(record, 'title')
        }
  
        if (valueAttr.indexOf('${') !== -1) {
          value = utils.parseVariables(record, valueAttr)
        } else {
          value = get(record, valueAttr)
        }
  
        return {
          label,
          value
        }
      })
    )
  }