export function groupByAndMap<T, U>(
  items: T[],
  groupBy: (item: T) => string,
  map: (item: T) => U,
): Record<string, U[]> {
  const groupings: Record<string, U[]> = {}

  for (const item of items) {
    const key = groupBy(item)

    if (!groupings[key]) {
      groupings[key] = []
    }

    groupings[key].push(map(item))
  }

  return groupings
}